JP2015503700A - Method and system for managing clearance in a piston engine - Google Patents

Abstract

The piston engine may include a non-contact bearing between the piston assembly and the cylinder. The piston can be configured to translate within the bore of the cylinder, and the non-contact bearing can be included in the gap between the piston assembly and the bore. Bearing fluid may be supplied to the gap via the piston assembly and / or cylinder to create a non-contact bearing. The bearing element may be used to direct or otherwise manage the flow of bearing fluid within the gap. The bearing element may include one or more holes, porous portions, and / or passages to direct bearing fluid to the gap.

Description

  As the engine compression ratio increases while maintaining a specific bore to stroke ratio, the surface to volume ratio at top dead center (TDC) increases, the temperature increases, and the pressure increases. This has three main consequences: 1) heat transfer from the combustion chamber increases, 2) combustion phase adjustment becomes difficult, and 3) friction and mechanical loss increase. Heat transfer increases as the aspect ratio at TDC (ie, the ratio of the bore diameter to the length of the combustion chamber) becomes smaller because the thermal boundary layer is a larger percentage of the overall volume. Combustion phase adjustment and achieving full combustion both present challenges due to the small volume realized in TDC. An increase in the combustion chamber pressure directly leads to an increase in the engineerably acting force. These large forces overload both mechanical connections and pressure excitation rings in the engine (eg, piston pins, piston rods, crankshafts), thus resulting in increased friction, wear, and / or failure. Can be.

  A major challenge associated with linear piston engines is the efficient conversion of piston kinetic energy into mechanical work and / or electrical energy. The space between the piston and cylinder wall, referred to herein as a “gap”, maintains piston alignment, prevents piston wall contact and associated friction loss, and It is important in controlling the gas leakage (eg blow-by). The clearance may be affected by imbalance forces acting on the piston, thermally induced expansion or contraction (eg, solid deformation), changing engine conditions, or other related factors. Management of clearance, piston temperature, cylinder temperature, or a combination thereof may be desired in some applications.

  In some embodiments, the piston engine may include a piston and cylinder assembly, and may include a fluid bearing in a gap between the cylinder bore and the piston assembly. The piston assembly may be axially translatable within the bore, and the piston face may contact the combustion section of the cylinder and face one end of the cylinder. At least one bearing element may provide a bearing fluid flow to a gap between the bore and the piston assembly to form a fluid bearing. In some embodiments, the bearing element is part of a piston assembly and may provide a flow of bearing fluid radially outward, the piston assembly including a fluid passage and directing the bearing fluid. In some embodiments, the bearing element may be part of a cylinder and provide a flow of bearing fluid radially inward, and the cylinder may include a fluid passage and direct the bearing fluid. The bearing element may include holes, squirting surfaces, any other suitable fluid outlet, or any combination thereof to provide bearing fluid to the gap.

  In some embodiments, the piston engine may include a piston cylinder assembly that includes a piston and a cylinder having self-aligning features. The piston may be configured to translate axially within the bore of the cylinder. In some embodiments, the piston may be part of a piston assembly that translates axially within the bore of the cylinder. The cylinder may include a combustion section that may contain combustion products. Blow-by gas from the combustion section can flow axially from the combustion section, beyond the piston face, through the gap between the piston and cylinder. The self-aligning feature may use blow-by gas flow to provide self-aligning force to the piston. The self-aligning feature can be a step, one or more slotted pockets, a tapered portion, any other suitable feature, or any combination thereof.

  In some embodiments, the piston engine may include a piston assembly having one or more heat pipes. The piston assembly may be configured to translate axially within the bore of the cylinder. The cylinder may include a combustion section that may contain combustion products, and thus the piston face of the piston assembly may experience an increase in temperature. In some embodiments, the heat pipe may be in thermal contact with the piston surface and may be able to transfer heat from the piston surface to the heat vessel. The first portion of the heat pipe may receive heat from the piston face, and the second portion of the heat pipe may transfer heat to the heat vessel. The heat pipe can include a fluid such as water, ethanol, ammonia, or sodium that can undergo a gas phase-liquid phase transition, for example.

  In some embodiments, the piston engine may include a cylinder liner configured to be positioned coaxially within a cylinder of the piston engine. The cylinder liner may include an inner surface that can form a gap with a piston assembly that is axially translatable within the cylinder liner. The cylinder liner may also include an outer surface that contacts the cylinder of the piston engine. The interface between the outer surface and the cylinder can include a fluid passage that can act as a conduit for pressure-controlled fluid. The cylinder liner can be configured to contract or expand radially based, at least in part, on the pressure-controlled fluid, and thus the gap can be adjusted.

  In some embodiments, the piston engine includes one or more fluid passages configured to provide controlled heating or cooling to the cylinder locally, selectively, responsively, or otherwise. obtain. The flow rate, temperature, pressure, or combination thereof of fluid supplied to the fluid passage may be adjusted by the control system to control the temperature of the piston engine. In some embodiments, the cylinder may include one or more local heating sources, such as one or more electric heaters, which may be controlled by a control system and provide local heating, for example.

  In some embodiments, the clearance between the coaxial piston assembly and the cylinder of the piston engine can be controlled. For example, at least one indicator, such as gap temperature, pressure, work interaction, and / or other suitable indicator, may be detected using one or more sensors. The control response may be determined by the processing equipment based at least in part on the indicator. The processing equipment may use the control interface to provide a control signal to at least one auxiliary system of the piston engine based at least in part on the control response. The at least one auxiliary system may adjust the gap based at least in part on the control signal.

The foregoing and other features of the present disclosure, their nature, and various advantages will become more apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings. Let's go.
FIG. 1 illustrates a cross-sectional view of an exemplary piston engine with an integrated linear electromagnetic machine (LEM) included as part of a piston assembly, gas spring, and cylinder, according to some embodiments of the present disclosure. FIG. 2 shows a cross-sectional view of an exemplary piston engine with a piston assembly, a gas spring, and an integrated linear electromagnetic machine (LEM), according to some embodiments of the present disclosure. FIG. 3 shows a cross-sectional view of an exemplary piston engine with a piston assembly having two pistons, a separate gas spring, and an integrated LEM, according to some embodiments of the present disclosure. FIG. 4 shows a cross-sectional view of an exemplary piston engine with two piston assemblies, a separate gas spring, and two integrated LEMs according to some embodiments of the present disclosure. FIG. 5 illustrates a perspective view of a portion of an exemplary piston assembly with self-aligning features, according to some embodiments of the present disclosure. FIG. 6 illustrates a cross-sectional view of an exemplary piston assembly and cylinder with blow-by from the combustion compartment, according to some embodiments of the present disclosure. FIG. 7 shows a cross-sectional view of the exemplary piston assembly and cylinder of FIG. 6 according to some embodiments of the present disclosure, the piston assembly being off-center. FIG. 8 shows a cross-sectional view of the illustrative piston assembly and cylinder of FIG. 6 according to some embodiments of the present disclosure, with the piston assembly centered. FIG. 9 illustrates a cross-sectional view of a portion of an exemplary piston engine with a piston assembly having features that can assist in aligning the piston assembly, according to some embodiments of the present disclosure. FIG. 10 illustrates a cross-sectional view of a portion of an exemplary piston engine with a piston assembly having pocketed self-aligning features, according to some embodiments of the present disclosure. FIG. 11 illustrates a cross-sectional view of a portion of an exemplary piston engine with a piston assembly having stepped self-aligning features, according to some embodiments of the present disclosure. FIG. 12 shows a cross-sectional view of a portion of an exemplary piston engine with a piston assembly having a tapered self-aligning feature, according to some embodiments of the present disclosure. FIG. 13 illustrates a perspective view of a portion of an exemplary piston assembly with a bearing element having a hole, according to some embodiments of the present disclosure. FIG. 14 shows a perspective view of a portion of an exemplary piston assembly with a porous bearing element, according to some embodiments of the present disclosure. FIG. 15 shows a cross-sectional view of an exemplary piston assembly in which a hydrodynamic bearing is delivered through the piston assembly, according to some embodiments of the present disclosure. FIG. 16 shows a cross-sectional view of an illustrative piston assembly and cylinder in which a hydrodynamic bearing is delivered through the piston assembly, according to some embodiments of the present disclosure. FIG. 17 illustrates a cross-sectional view of an illustrative piston assembly and cylinder in which a hydrodynamic bearing is delivered through the cylinder, according to some embodiments of the present disclosure. FIG. 18 shows a cross-sectional view of an illustrative arrangement of a piston assembly and cylinder having a translator having a fluid bearing and a fluid passage according to some embodiments of the present disclosure. FIG. 19 illustrates a cross-sectional view of an illustrative arrangement of a piston assembly and cylinder having a fluid bearing and a check valve, according to some embodiments of the present disclosure. FIG. 20 shows a cross-sectional view of an exemplary piston assembly and cylinder with a heat pipe included as part of the piston assembly, according to some embodiments of the present disclosure. FIG. 21 illustrates a cross-sectional view of an exemplary piston assembly with a heat pipe formed by an internal void according to some embodiments of the present disclosure. FIG. 22 shows a cross-sectional view of an exemplary piston engine having a piston assembly and a cylinder having a coolant passage and a heat pipe, according to some embodiments of the present disclosure. FIG. 23 illustrates a cross-sectional view of an illustrative piston assembly and cylinder with a deformable cylinder liner, according to some embodiments of the present disclosure. 24 shows a cross-sectional view of the illustrative piston assembly and cylinder of FIG. 23 with a deformable cylinder liner undergoing deformation, according to some embodiments of the present disclosure. FIG. 25 illustrates a cross-sectional view of an illustrative piston assembly and cylinder with a compartmentalized deformable cylinder liner, according to some embodiments of the present disclosure. FIG. 26 shows a cross-sectional view of an exemplary piston engine with a deformable cylinder liner according to some embodiments of the present disclosure. FIG. 27 shows a cross-sectional view of a portion of an exemplary piston engine with local coolant passages according to some embodiments of the present disclosure. FIG. 28 shows a cross-sectional view of a portion of an exemplary piston engine with local coolant passages according to some embodiments of the present disclosure. FIG. 29 shows a cross-sectional view of a portion of an exemplary piston engine with a local heat source, including an electric heater, according to some embodiments of the present disclosure. FIG. 30 shows a cross-sectional view of a portion of an exemplary piston engine that includes a fluid passage that can be used for heating, cooling, or both, according to some embodiments of the present disclosure. FIG. 31 shows a perspective view of a portion of an exemplary piston assembly having bearing elements and self-aligning features, according to some embodiments of the present disclosure. FIG. 32 is an illustrative piston with a piston assembly and a cylinder having a deformable cylinder liner and a coolant passage having bearing elements, heat pipes, and self-aligning features, according to some embodiments of the present disclosure. A cross-sectional view of the engine is shown. FIG. 33 is a block diagram of an exemplary control arrangement for a piston engine according to some embodiments of the present disclosure. FIG. 34 is a flowchart of illustrative steps for adjusting piston engine clearances according to some embodiments of the present disclosure. FIG. 35 is a flowchart of illustrative steps for adjusting one or more characteristics of a piston engine, according to some embodiments of the present disclosure.

  The present disclosure is directed to managing piston engine clearances and / or other characteristics. Although discussed in the context of a free piston engine, the techniques and arrangements disclosed herein can be applied to non-free piston engines or other suitable mechanical systems. As used herein, the term “piston engine” is intended to refer to both free and non-free piston engines.

  A piston engine operating using any suitable thermodynamic cycle can include a piston and cylinder assembly to achieve displacement work. The piston and cylinder can be separated by a relatively small gap, and the piston translates axially within the bore of the cylinder. In some embodiments, the piston may be included as part of a “piston assembly”, and the piston assembly may be movable in conjunction as a substantially rigid assembly at least partially within the bore. Piston seals (eg, piston rings), bearing elements, frames, piston rods, translators, and / or other components. The gap can be constant or variable along the radial periphery of the piston assembly or its components (eg, the gap can be described by a thickness value, a profile or field of values, and / or a symmetry metric). A cylinder is a combustion section in which oxidizing substances (eg air, polluted air, oxygen) and fuel (eg gaseous or liquid hydrocarbon fuel) can be supplied separately or as a premixed mixture for combustion. Can be included. Expansion of the hot combustion product causes piston displacement. Work uses a linear electromagnetic machine (LEM) with mechanical linkage (eg, using a piston rod and crankshaft assembly), electromagnetic interaction (eg, a translator and stator as described in this disclosure) ), Gas coupling (eg, using two pistons that interact through an intermediate gas volume), any other suitable work extraction technique, or any combination thereof, extracted from piston motion Can be done. Compression of air and / or fuel by the piston-cylinder assembly can also be achieved using piston motion. In some embodiments, the compression work may be provided by gas drive, LEM, or both.

  1-4 illustrate an exemplary piston engine that may benefit from the teachings of the present disclosure. It will be appreciated that the teachings of the present disclosure may be applied to any other suitable piston engine in addition to those illustrated in the figures and described herein. Also, although not shown in FIGS. 1-4, the piston engine may be a cooling subsystem, air delivery system, fuel delivery system, ignition subsystem, exhaust system, electronic control system, and / or other suitable subsystem, etc. It will be understood that the phrase “piston engine” may refer to a suitable collection of components and subsystems.

  FIG. 1 illustrates a cross-sectional view of an exemplary piston engine 100 with a piston assembly 110, a gas spring 148, and an integrated linear electromagnetic machine (LEM) 160, according to some embodiments of the present disclosure. Piston engine 100 includes a cylinder 140 having a bore 134 and a combustion section 130, and a piston assembly 110. In the illustrated embodiment, the piston assembly 110 includes two piston faces 112, piston seals 114 and 115, and a translator 116. Although not shown in FIG. 1, the piston assembly 110 may include bearing elements, piston rods, any other suitable components, or any combination thereof. In the illustrated embodiment, the piston assembly 110 is configured to lie completely within the bore 134 of the cylinder 140 and translate substantially along the axis 150. Cylinder 140, as shown in FIG. 1, exhaust / inject port 170 (for exhaust removal and / or reactant injection), intake port 180 (for inhalation of air and / or air / fuel mixture), and drive A gas port 190 (for supplying and / or removing driving gas) is included. Piston engine 100 may operate using a two-stroke cycle, a four-stroke cycle, any other suitable cycle, or any combination thereof. A collision plate 108 may be included in some embodiments to assist collision resistance, eg, collision resistance during combustion. Valves and / or other fluid components may be used with some or all of the ports 170, 180, and 190 to control the flow of fluid into and out of the piston engine 100, but are not required.

  Cylinder 140 can include a portion 132 where combustion, gas expansion, and exhaust can occur, a portion 168 where electromagnetic work interaction can occur, and a portion 178 where gas drive and gas springs can occur. Portions 132, 168, and 178 may depend on the configuration of cylinder 140 and the position of piston assembly 110 within bore 134 of cylinder 140. A stator 162 used to extract electromagnetic work from the motion of the translator 116 may be included as part of the cylinder 140, as shown in FIG.

  The translator 116 may be translated through the stator 162 during the expansion stroke of the piston assembly 110 in the cylinder 140 due to combustion of oxidant and fuel in the combustion compartment 130. Movement of the translator 116 relative to the stator 162 can generate current and corresponding electrical work. LEM 160 may include a permanent magnet machine, an induction machine, a switched reluctance machine, any other suitable electromagnetic machine, or any combination thereof. For example, the translator 116 can include a permanent magnet, and the stator 162 can include a wire coil that can conduct an induced current generated by the motion of the translator 116.

  FIG. 2 shows a cross-sectional view of an exemplary piston engine 200 with a piston assembly 210, a gas spring 248, and a LEM 260, according to some embodiments of the present disclosure. Piston engine 200 includes a cylinder 240 having a bore 234, a piston assembly 210, and a combustion section 230. In the illustrated embodiment, the piston assembly 210 includes a piston surface 212, a piston seal 214 (eg, a piston ring, a sealing surface), a translator 216, and a piston rod 218. Although not shown in FIG. 2, piston assembly 210 may include a bearing element, any other suitable component, or any combination thereof. In the illustrated embodiment, the piston assembly 210 is partially positioned within the bore 234 of the cylinder 240 and is configured to translate substantially along the axis 250. The cylinder 240 includes a gas seal 242 (to reduce or prevent gas leakage while allowing relative piston movement) and an exhaust / inject port 270 (exhaust removal and / or reactants as shown in FIG. 2). An intake port 280 (for inhaling air and / or air / fuel mixture) and a drive gas port 290 (for supplying and / or removing drive gas). Piston engine 200 may operate using a two-stroke cycle, a four-stroke cycle, any other suitable cycle, or any combination thereof. A collision plate 208 may be included in some embodiments.

  The cylinder 240 can include a portion 232 where combustion, gas expansion, and exhaust can occur, and a portion 278 where gas drive and gas spring can occur. Portion 268 can include LEM 260 that can be included separately from cylinder 240 and where electromagnetic work interactions can occur. Portions 232, 268, and 278 may depend on the configuration of cylinder 240 and the position of piston assembly 210 within bore 234 of cylinder 240. The stator 262 used to extract electromagnetic work from the motion of the translator 216 is not required, but can be separate from the cylinder 240, as shown in FIG.

  FIG. 3 illustrates a cross-sectional view of an exemplary piston engine 300 with a piston assembly 310 having two pistons 311 and 313, a separate gas spring 348, and a LEM 360, according to some embodiments of the present disclosure. Piston engine 300 includes cylinders 340 and 341 having bores 334 and 335, a piston assembly 310, and a combustion section 330, respectively. In the illustrated embodiment, the piston assembly 310 includes a piston surface 312, a translator 316, piston seals 314 and 315, and a piston rod 318. Although not shown in FIG. 3, piston assembly 310 may include bearing elements, any other suitable components, or any combination thereof. In the illustrated embodiment, the piston assembly 310 is located partially within the bore 334 of the cylinder 340 and partially within the bore 335 of the cylinder 341 and translates substantially along the axis 350. Configured as follows. The cylinder 340 includes a gas seal 342 (to reduce or prevent gas leakage while allowing relative piston motion) and an exhaust / inject port 370 (exhaust removal and / or reactant, as shown in FIG. 3). An intake port 380 (for inhaling air and / or air / fuel mixture) and a gas port 395 (for removing blow-by or supplying air). As shown in FIG. 3, the cylinder 341 includes a gas seal 343 (to reduce or prevent gas leakage while allowing relative piston motion) and a drive gas port 390 (for supplying and / or removing drive gas). ). Piston engine 300 may operate using a two-stroke cycle, a four-stroke cycle, any other suitable cycle, or any combination thereof. A collision plate 308 may be included in some embodiments.

  The cylinder 340 can include a portion 332 where combustion, gas expansion, and exhaust can occur. The cylinder 341 can include a portion 378 where a gas drive and a gas spring can occur. Portion 368 can be included between cylinders 340 and 341 and can include a LEM where electromagnetic work interaction can occur. Portions 332, 368, and 378 may depend on the configuration of cylinders 340 and 341 and the position of piston assembly 310 within bores 334 and 335 of each cylinder 340 and 341. The stator 362 used to extract electromagnetic work from the motion of the translator 316 is not required, but can be separate from the cylinders 340 and 341 as shown in FIG.

  FIG. 4 illustrates a cross-sectional view of an exemplary piston engine 400 with two piston assemblies 410 and 411, separated gas springs 448 and 449, and two LEMs 460 and 461, according to some embodiments of the present disclosure. Show. The piston engine 400 is symmetrical about the exhaust / injection port 370, as shown, and is substantially equivalent to two piston engines 300 having a single combustion chamber. It will be appreciated that other two-piston arrangements may be achieved in accordance with the present disclosure, but need not be symmetric and the piston engine 400 is an illustrative example.

  For further details regarding piston engines such as piston engines 100, 200, 300, and 400 and their operation and characteristics, see Simpson, et al., US patent application Ser. No. 12 / 953,270, Simpson, et al., US patent application Ser. No. 12/953. , 277, Simpson, et al., U.S. Patent Application No. 13 / 102,916, and Roelle et al., U.S. Patent Application No. 13 / 028,053, all of which are hereby incorporated by reference in their entirety. Incorporated into.

(Self-aligning piston)
In some embodiments, the piston may include one or more features that provide self-alignment to the cylinders of the piston engine.

  FIG. 5 illustrates a perspective view of a portion of an exemplary piston assembly 500 with a self-aligning feature 506, according to some embodiments of the present disclosure. Piston assembly 500 may include piston face 502, element 504, self-aligning feature 506, any other suitable component (not shown), or any combination thereof. In some embodiments, the self-aligning feature 506 can be part of the element 504. For example, element 504 can be a bearing element (eg, a hydrostatic bearing) and self-aligning feature 506 can be a machined step in the bearing element or other suitable feature. In some embodiments, the self-aligning feature 506 can be part of the piston face 502. For example, the self-aligning feature 506 can be a step, one or more slotted pockets, a tapered portion, or other feature included within the piston assembly 500. In some embodiments, the piston assembly may include one or more features, components, or both that assist in aligning the piston assembly. For example, the piston assembly can include self-aligning features and features that can assist in equalizing pressure on one or more lateral surfaces of the piston assembly that can assist in aligning the piston. Although not shown in FIG. 5, the piston assembly 500 may optionally include a piston rod, translator, piston ring, fluid bearing, any other suitable component, or any combination thereof.

  FIG. 6 illustrates a cross-sectional view of an exemplary arrangement 600 of piston assembly 610 and cylinder 620 with blow-by (indicated by arrow 640) from combustion section 630, according to some embodiments of the present disclosure. In some embodiments, the piston surface 602 can be any of the combustion compartment 630 (shown schematically in FIG. 6), a gas drive compartment (not shown in FIG. 6), a piston engine cylinder (not shown). Other suitable compartments, or any combination thereof may be contacted. The blow-by can flow axially along the piston assembly 610 from the combustion section 630 and around the piston face 602. In some embodiments, the interaction between the blow-by and the self-aligning feature 616 can act to align the central piston assembly 610. For example, a pressure distribution can be created in the gap between the piston assembly 610 and the cylinder 620 to act to align the central piston assembly 610. The blow-by is supplied to the gap from the combustion section, gas-driven section, or other suitable section and can operate at any suitable pressure (eg, operate at a pressure of 20-800 bar or other suitable pressure).

FIG. 7 shows a cross-sectional view of an exemplary piston assembly 610 and cylinder 620 according to some embodiments of the present disclosure, where the piston assembly 610 is offset from the center. Center axis 750 of cylinder 620 illustrates the geometric center axis of the bore of cylinder 620. When the piston assembly 610 is offset from the center in the cylinder 620, as shown in FIG. 7, for the piston assembly along the side of the piston assembly 610 (ie, at a radius R that can vary with θ and Z). The pressure field P ₁ (R, θ, Z) in cylindrical coordinates can be non-uniform in the circumferential direction (ie, in the θ direction) at a given axial position Z. FIG. 8 shows a cross-sectional view of an exemplary piston assembly 610 and cylinder 620 according to some embodiments of the present disclosure, with the piston assembly 610 centered about a central axis 750. When the piston assembly 610 is centered in the cylinder 620, the pressure field P ₂ (R, θ, Z) of the piston assembly 610 is substantially at a given axial position Z, as shown in FIG. Furthermore, it can be uniform in the circumferential direction. In some embodiments, the pressure field of the centered piston may be non-uniform, but integrating over the lateral surface of the piston results in a substantially zero resultant force. For example, a piston assembly having a slotted pocket may have a non-uniform circumferential pressure field due to the pocket, but may provide zero resultant force.

  FIG. 9 illustrates a cross-sectional view of a portion of an exemplary piston engine 900 with a piston assembly 910 having features 912 that can assist in aligning the piston assembly 910 according to some embodiments of the present disclosure. . In some embodiments, features such as feature 912 may be included in the piston assembly along with self-aligning features (eg, any of the self-aligning features of FIGS. 10-12). The feature 912 includes one or more grooves extending around the entire circumference of the piston assembly 910 that can assist in equalizing the pressure field within the gap 950 of FIG. 9, as illustrated in FIG. May be included. Feature 912 can also act as a linear labyrinth seal to reduce the axial flow rate in gap 950. In FIG. 9, shown schematically as a groove, any suitable feature or combination of features may be used to assist in aligning according to the present disclosure.

  FIG. 10 illustrates a cross-sectional view of a portion of an exemplary piston engine 1000 with a piston assembly 1010 having a pocketed self-aligning feature 1012 with one or more slots 1014 according to some embodiments of the present disclosure. Show. Self-aligning features 1012 may include one or more pockets, each extending partially around the circumference of piston assembly 1010. The slot 1014 can include one or more slots (eg, corresponding to one or more pockets) that can act as a guide for blow-by entering the pocket. Although shown as being located on a lateral surface of the piston assembly 1010, in some embodiments, the slots can be included within the piston assembly and can be fed from any suitable source. For example, the self-aligning feature 1012 may be aligned with three slotted pockets, each centered 120 ° apart on the circumference and each extending less than 120 ° along the circumference. 3 corresponding slots 1014 may be included which may allow the high pressure region 1060 to flow into the pocket. Any suitable arrangement of segmented pockets can be used in accordance with the present disclosure, including any suitable number of pockets.

  FIG. 11 illustrates a cross-sectional view of a portion of an exemplary piston engine 1100 with a piston assembly 1110 having a stepped self-aligning feature 1112 according to some embodiments of the present disclosure. The self-aligning feature 1112 may include a step that extends around the entire circumference of the piston assembly 1110. The steps may include any suitable absolute and / or relative dimensions. In an illustrative example, the gap in the stage (ie, relatively close to the piston face 1102) can be about twice the gap in the larger diameter region of the piston assembly. In some embodiments, the piston assembly may include a segmented step, similar to the slotted pocket arrangement of FIG. 10, but the pocket extends through the piston face 1102 and thus the slot is It does not need to be included.

  FIG. 12 illustrates a cross-sectional view of a portion of an exemplary piston engine 1200 with a piston assembly 1210 having a tapered self-aligning feature 1212 according to some embodiments of the present disclosure. The self-aligning feature 1212 may include a tapered portion that extends around the entire circumference of the piston assembly 1210 such that the diameter at the piston face 1202 is relatively contracted. The taper can include any suitable absolute and / or relative dimensions. In an illustrative embodiment, the gap at the taper's small diameter (ie, relatively close to the piston face 1202) may be about twice the gap in the larger diameter region of the piston assembly. In some embodiments, the piston assembly may include two or more tapered sections around the circumference, similar to the slotted pocket arrangement of FIG. 10, with the taper extending through the piston face 1202. .

  In some embodiments, self-aligning features 1012, 1112, and 1212, feature 912, and some or all of other suitable self-aligning features or other features may be combined. For example, the piston assembly can include a taper, a step, and a series of grooves (eg, a labyrinth) to provide alignment. The self-aligning feature is in contact with the combustion compartment, gas drive compartment, gas spring compartment, any other suitable piston face that allows blow-by gas to flow past the piston face, or any combination thereof. Can be used in the vicinity of the piston face. For example, referring to the piston engine 300 of FIG. 3, self-aligning features can be included near any of the piston faces 312.

(Non-contact bearing)
In some embodiments, non-contact bearings can be used between the piston and the corresponding cylinder. Non-contact bearings can include, for example, gas static bearings, hydrostatic bearings, or other suitable non-contact bearings that can move or be stationary. Non-contact bearings may include a thin film of fluid that separates the piston and cylinder walls, reducing friction and associated work loss. In some embodiments, the use of gas hydrostatic bearings may allow oilless operation of the piston and cylinder assembly of the piston engine, and therefore the piston engine need not require an auxiliary oiling system, which Some aspects of the engine structure can be simplified. In some embodiments, the non-contact bearing may include oil as the bearing fluid. The bearing fluid may include, for example, air, nitrogen, exhaust, oil, liquid water, water vapor, liquid CO ₂ , gaseous CO ₂ , hydraulic fluid, any other suitable fluid, or any combination thereof. The fluid used in the hydrodynamic bearing can be supplied through a piston assembly, a cylinder, or both.

  FIG. 13 illustrates a perspective view of a portion of an exemplary piston assembly 1300 with a bearing element 1310 having a hole 1312 according to some embodiments of the present disclosure. The holes 1312 can be arranged in a pattern, randomly arranged, or any combination thereof. The holes 1312 can have any suitable dimensions. For example, in some embodiments, the holes 1312 can range from a few thousandths of an inch to 1/8 inches or more. In some embodiments, the size of the hole 1310 may be selected based on the relative flow restriction or effective area of the hole relative to one or more other flow restrictions or effective areas. For example, the hole may be sized to provide a flow restriction that is as much as the flow restriction in the exhaust path of the bearing fluid downstream of the hole 1310. When piston assembly 1300 translates within the bore of a suitable cylinder by force on piston surface 1302 or other suitable piston surface (not shown) of piston assembly 1300, the bearing element maintains alignment. Can help. Fluid may be supplied from any suitable fluid source, as indicated by arrow 1322, and may be distributed within piston assembly 1300 via an internal fluid passage (not shown) to hole 1312. After flowing out of the holes 1312, the fluid may flow along at least a portion of the piston assembly 1300 through the gap. The outward flow of fluid from the bearing element 1310 may assist in preventing and / or reducing piston assembly-cylinder contact, as indicated by arrow 1320.

  Although shown in FIG. 13 as a hole, any suitable port can be used to provide fluid to the gap and serve as a fluid bearing. For example, a gap between mating parts can be used to provide fluid to the gap. In a further embodiment, an orifice in the form of a ring that extends partially or fully around the circumference of the piston assembly can be used to provide fluid to the gap. In some embodiments, the bearing element 1310 may include a port that is sufficiently small (eg, smaller than the mean free path of the bearing fluid) to provide eruption.

  FIG. 14 shows a perspective view of a portion of an exemplary piston assembly 1400 with a porous bearing element 1410 according to some embodiments of the present disclosure. When the piston assembly 1400 translates within the bore of a suitable cylinder by force on the piston surface 1402 or other suitable piston surface (not shown) of the piston assembly 1400, the bearing element maintains alignment. Can help. The fluid can be supplied from any suitable fluid source, as indicated by arrow 1422, can be distributed into piston assembly 1400 via an internal fluid passage (not shown), and then any of bearing elements 1410 Can flow through a suitable portion of the void space. The bearing element 1410 can have any suitable porosity and pore size. After exiting the lateral surface of the bearing element 1410, the gas may flow along at least a portion of the piston assembly 1400 through the gap. The outward flow of fluid from the bearing may assist in preventing and / or reducing piston assembly-cylinder contact, as indicated by arrow 1420. The bearing element 1410 can be constructed from any suitable material having a porosity that can allow fluid to flow. For example, porous bearing elements can be graphite, sintered metal (eg, iron, steel, bronze), sintered or otherwise porous ceramic (eg, silicon carbide, alumina, magnesia), sintered or otherwise. Of any other suitable material, or any combination thereof. In some embodiments, the bearing element 1410 may have a pore size that is sufficiently small (eg, smaller than the mean free path of the bearing fluid) to allow eruption.

  FIG. 15 illustrates a cross-sectional view of an exemplary piston assembly 1500 according to some embodiments of the present disclosure, where the fluid bearing 1510 is fed through the piston assembly 1500. Piston assembly 1500 may include piston 1502, bearing element 1510, frame 1550, fastener 1590, any other suitable component not shown in FIG. 15, or any combination thereof. Piston assembly 1500 may be configured to fit into a bore of a cylinder of a piston engine and may be configured to translate substantially along an axis on or near the centerline of the bore. The bearing element 1510 distributes bearing fluid from one or more inlet ports 1512 to one or more ports or surfaces as indicated by arrows 1522 and flows radially outward as indicated by arrows 1520. A fluid passage 1560 that may be provided. In some embodiments, the bearing element 1510 may include an assembly of multiple components. In some embodiments, the piston 1502 can optionally include self-aligning features or other suitable features (not shown).

  FIG. 16 illustrates a cross-sectional view of an exemplary piston assembly 1610 and cylinder 1620, according to some embodiments of the present disclosure, in which a fluid bearing 1612 (eg, a fluid layer located within a gap arising at least partially from the bearing element 1618). ) Is fed through the piston assembly 1610. Piston assembly 1610 includes an internal passage 1614 that can receive bearing fluid 1616. The bearing element 1618 is part of a piston assembly 1610 that includes holes or porous portions from which bearing fluid can flow into the fluid bearing 1612. The bearing element 1618 may be an integral part of the piston (as shown in FIG. 16), another part of the piston assembly 1610, a separate component that is fitted to the piston assembly 1610 (eg, using an interference fit or fastener). Can have any other suitable arrangement (by mounting), or any combination thereof. The fluid bearing 1612 may assist in aligning the piston assembly 1610 about an axis 1650 that represents the center of the bore of the cylinder 1620.

  FIG. 17 illustrates a cross-sectional view of an exemplary piston assembly 1710 and cylinder 1720 according to some embodiments of the present disclosure, where the fluid bearing 1712 is fed through the cylinder 1720. Cylinder 1720 includes an internal passage 1714 that can receive bearing fluid 1716. The bearing element 1718 is a part of a cylinder 1720 that includes a hole or squirting surface from which fluid can flow into a fluid bearing 1712 within a suitable clearance between the piston assembly 1710 and the cylinder 1720. The bearing element 1718 has any other suitable arrangement that is an integral part of the cylinder 1720 (as shown in FIG. 17), a separate component (eg, an insert or liner, etc.) that fits into the cylinder 1720. Or any combination thereof. Fluid bearing 1712 may assist in aligning piston assembly 1710 about axis 1750, which represents the center of the bore of cylinder 1720. In some embodiments, the cylinder may include one or more bearing elements that may provide bearing fluid to one or more corresponding fluid bearings. For example, in some embodiments, the cylinder bore includes a plurality of bearing elements, each with a separate and controllable fluid source capable of delivering bearing fluid to a plurality of locations within the cylinder bore. obtain.

  In some embodiments, low-by gas may be routed to reduce or prevent flow of blow-by gas into a portion of the gap adjacent to the bearing element. For example, blow-by gas may be routed through a cylinder, piston assembly, or both such that the flow of blow-by gas does not substantially alter the flow of bearing fluid in the gap. For example, some changes in bearing gas flow due to other flows, such as blow-by gas, can adversely affect the ability of the bearing fluid to prevent piston-cylinder contact. Blow-by gas routing may, for example, allow the bearing fluid exhaust pressure to be relatively well below the fluid delivery pressure (eg, allow for a greater pressure drop of the bearing fluid), which may be desired flow rate. And may provide bearing properties.

  FIG. 18 shows a cross-sectional view of an exemplary arrangement 1800 of piston assembly 1810 and cylinder 1820 with bearing elements 1812 and 1813 and a translator 1814 having a fluid passage 1875 in accordance with some embodiments of the present disclosure. Piston surface 1802 may contact a gas spring (eg, a gas drive section) of array 1800, while piston surface 1804 may contact a combustion section of array 1800. The array 1800 can include a stator 1815 that can electromagnetically interact with the translator 1814.

  In the illustrated embodiment, bearing fluid 1874 is supplied to conduit 1870 where conduit 1872 is connected via seal 1871. Seal 1871, including conduit 1872, as shown in FIG. 18, allows piston assembly 1810 to translate about axis 1850 while maintaining a pressure seal between conduits 1870 and 1872. obtain. The interior of conduit 1872 is coupled to a fluid passage 1875 located within translator 1814 from which bearing fluid 1874 can flow into passage 1816. Passage 1816 delivers bearing fluid 1874 to bearing elements 1812 and 1813, from which bearing fluid 1874 flows into the fluid bearing in the gap between piston assembly 1810 and cylinder 1820. In some embodiments (not shown), conduit 1870, conduit 1872, or both may be flexible and allow relative movement. For example, in some embodiments (not shown), the conduit 1870 can be a flexible hose that is connected directly to the translator 1814 via a suitable hose coupling (eg, therefore, the conduit 1872 is Need not be included).

  FIG. 19 illustrates a cross-sectional view of an exemplary arrangement 1900 of piston assembly 1910 and cylinder 1920 with bearing elements 1912 and 1913 and valve 1970 according to some embodiments of the present disclosure. The piston surface 1902 can contact a gas spring (eg, a gas drive section) of the array 1900, while the piston surface 1904 can contact the combustion section of the array 1900. The array 1900 can include a stator 1915 that can interact electromagnetically with the translator 1914.

  In the illustrated embodiment, at least a portion of the fluid in the gas spring 1976 is supplied to the passage 1916 as a bearing fluid via a valve 1970 located on the piston face 1902 (eg, as indicated by arrow 1974). ). The valve 1970 may include an active or passive valve, or other suitable ported device that provides control of fluid flow in one or more directions. For example, valve 1970 may be a reed valve, ball valve, needle valve, ball check valve, diaphragm check valve, static flow restriction in a conduit that provides different resistance for different flow directions, any other suitable It may include a valve, electronic controller or other active positioning system, any other suitable device, or any combination thereof. Passage 1916 delivers bearing fluid 1974 to bearing elements 1912 and 1913 from which the bearing fluid flows into the fluid bearing in the gap between piston assembly 1910 and cylinder 1920. In some embodiments, the valve 1970 can be a check valve. Thus, as piston assembly 1910 translates along axis 1950 and fluid is supplied and / or removed from gas spring 1976 via port 1990 (eg, which can include one or more valves). , The pressure in the gas spring 1976 can reach a cracking pressure, and fluid can flow through the valve 1970 into the passage 1916. The cracking pressure of the valve 1970 can be any suitable value, and in some embodiments can be actively adjustable. In some embodiments, the valve 1970 may be actively controllable, and flow in either direction may be controlled by controlling the orifice of the valve 1970 or other flow restriction.

  In some embodiments, the bearing element can be an integral part of the piston. For example, the piston may have a collection of machined passages and holes that provide bearing fluid to the gap. In some such embodiments, the piston is not necessary, but can be part of the piston assembly. The bearing element can be a graphite element, a metal element with machined features, a sintered metal element, a porous ceramic element, a non-porous ceramic element, any other suitable element of a suitable material, or any A combination thereof may be included.

(Cylinder and / or piston temperature control)
In some embodiments, the temperature of the piston (or assembly thereof), cylinder, or both can be controlled or otherwise managed. Piston (or assembly thereof) and / or cylinder temperature management may assist in maintaining or otherwise managing the clearance by managing thermal deformation of one or more components of the piston engine.

  In some embodiments, one or more heat pipes may be used to affect the heat transfer of the piston assembly. The heat pipe may include, for example, a fluid conduit that is configured to assist heat transfer to and from the configurable piston engine. The piston face of the piston assembly can undergo a temperature rise due to combustion. The use of a heat pipe may assist in removing heat from the piston face, any other suitable part of the piston assembly, or any other suitable component and reducing the operating temperature of the component. For example, the heat pipe from the piston surface to a heat vessel such as a bearing element, gap, cylinder bore surface, piston rod cooled by a coolant, any other suitable heat vessel, or any combination thereof. Can transfer heat.

  The heat pipe may include a fluid conduit that may be filled with a suitable fluid, such as, for example, water, ethanol, ammonia, sodium, or any other suitable fluid or mixture. The latent heat associated with fluid phase transitions generally far exceeds the transfer of sensible energy due to temperature differences. In addition, fluid phase transitions can occur at substantially constant or otherwise limited temperatures (which can depend on pressure and any impurities present), which is a relatively high temperature in the piston engine. May assist in reducing the slope. The heat pipe may be arranged as part of the piston assembly that is in thermal contact with the piston face of the piston assembly. In some embodiments, the linear motion of the piston assembly with the heat pipe assists in transporting fluid within the heat pipe and thus assists in heat transfer from the piston face to the relatively cooler part of the piston engine. Can do.

  It will be understood that the phrase “thermal contact” between components refers to the capability of operational heat transfer between the components. For example, the heat pipe can be arranged in contact with the piston face and can transfer heat from the piston face and thus can be in “direct” thermal contact with the piston face. In a further embodiment, the heat pipe may contact the piston frame, which may contact the piston face, the heat pipe may transfer heat from the piston frame, which may transfer heat from the piston face, and thus the heat pipe is , May be in “indirect” thermal contact with the piston face.

  FIG. 20 shows a cross-sectional view of an exemplary piston assembly 2010 and cylinder 2020 of a piston engine 2000 with a heat pipe 2080 included as part of a piston assembly, according to some embodiments of the present disclosure. The heat pipe 2080, which may be a pipe or other fluid conduit, may include a fluid 2082 that may undergo a gas phase-liquid phase transition during operation of the piston engine 2000. Heat transfer (indicated by arrow 2024) can occur from the combustion section 2030 to the piston face 2002 during engine operation. Heat transfer (indicated by arrow 2024) may further occur from piston surface 2020 to portion 2084 of heat pipe 2080, which may assist in reducing, maintaining, or both the temperature of piston surface 2020. Heat transfer within the heat pipe 2080 can occur from the portion 2084 of the heat pipe 2080 to the portion 2086 of the heat pipe 2080. Portion 2086 may transfer heat to a portion of piston assembly 2010 away from piston surface 2002, such as the distal end of combustion section 2030 and the end of cylinder 2020 relatively close to portion 2086. For example, the heat pipe 2080 may assist in transferring heat 2024 from the combustion section 2030 radially outward to the bearing surface, gap, and then to the cylinder, where, for example, the coolant in the coolant passage Can be further communicated. In a further example, the heat pipe 2080 may assist in transferring heat from the combustion section 2024 to the gas drive section 2040 of the cylinder 2020.

  FIG. 21 illustrates a cross-sectional view of an exemplary piston assembly 2100 with a heat pipe 2180 formed by an internal void according to some embodiments of the present disclosure. Piston assembly 2100 may include a piston 2102, an element 2110, a frame 2150, a fastener 2190, any other suitable component not shown in FIG. 21, or any combination thereof. The piston assembly 2100 may be configured to fit into a bore of a cylinder of a piston engine and may be configured to translate substantially along an axis on or near the bore centerline. Element 2110 includes (not shown) a bearing element (eg, with a bearing passage), piston ring, frame, any other suitable component, any other suitable feature, or any combination thereof. obtain. Fluid in heat pipe 2180 can be filled, vented, or otherwise regulated using port 2182, which can include valves (eg, check valves or shut-off valves), plugs, or other components. . In some embodiments, the heat pipe 2180 with port 2182 may be fillable, vented, or otherwise adjustable during operation of the piston engine. In some embodiments, the heat pipe 2180 with port 2182 does not need to be filled, vented, or otherwise adjustable during operation of the piston engine, and thus, while the piston engine is not operating. Can be adjusted.

  In some embodiments, a plurality of heat pipes may be included on the diameter near the periphery of the piston assembly to assist in transferring heat from the piston face to the gap and the inner cylinder wall. In an illustrative embodiment, 6-12 heat pipes may be oriented axially arranged on the diameter near the periphery of the piston assembly, but any suitable number of heat pipes may be in such an annular arrangement. Can be used. In some embodiments, an annular heat pipe may be included in the piston assembly to assist in transferring heat to the gap. For example, the annular void in the piston assembly can be filled and sealed with a suitable fluid during operation.

  FIG. 22 illustrates a cross-sectional view of an exemplary piston engine 2200 having a piston assembly 2210 and a cylinder 2220 having coolant passages 2222 and 2238 and a heat pipe 2224 according to some embodiments of the present disclosure. In some embodiments, the piston engine 2200 may include a coolant passage 2222 to assist in controlling or otherwise limiting the temperature of one or more components of the piston engine 2200. Temperature control can also be used to control the size and / or shape of the cylinder bore (eg, by controlling thermal deformation), which improves or otherwise adjusts blow-by characteristics and / or bearing performance. obtain. As shown schematically in FIG. 22, the cylinder 2220 has one or more ports that can supply and return coolant fluid, as indicated by arrows 2230 and 2234, and arrows 2232 and 2236, respectively. May include an internal passage. As shown, the coolant passage 2222 and the coolant passage 2238 include an annular gap, but any suitable arrangement may be used in accordance with the present disclosure. In some embodiments, a coolant such as ethylene glycol, propylene glycol, water, alcohol, air, any other suitable fluid, or any combination thereof (e.g., ethylene glycol diluted with water) Coolant passages 2222 and 2238 may be supplied. In some embodiments (not shown), piston engine 2200 includes a pump, radiator, temperature regulator, pressure regulator, fluid handling conduit, any other suitable component, or any combination thereof. A coolant subsystem may be included. In some embodiments, the coolant passage 2222 and the coolant passage 2238 can be interconnected within the cylinder 2220 and thus can be controlled as a single set of passages. In some embodiments, the coolant passage 2222 and the coolant passage 2238 do not need to be interconnected within the cylinder 2220 and may be separately controllable. For example, in some embodiments, the coolant passage 2222 and the coolant passage can optionally assist in cooling different zones of the cylinder 2220, and thus each zone can be cooled separately. In the illustrative example, the control system may determine that the clearance between the piston assembly 2210 and the cylinder 2220 is too large when the piston is in the combustion section 2270. Thus, the flow rate of the coolant supplied to the coolant passage 2222, which is relatively closer to the TDC than the coolant passage 2238, is increased, cooling the cylinder, reducing the bore (via thermal contraction), and thus The gap can be reduced. Any suitable number of separate coolant passages can be used to provide selective cooling arranged in any suitable configuration in accordance with the present disclosure. In some embodiments, the cylinder 2220 may include one or more heat pipes 2224 to assist in controlling or otherwise limiting the temperature of one or more components of the piston engine 2200. The one or more heat pipes 2224 may be included in the cylinder 2220 in any suitable arrangement and may include any suitable heat pipe fluid. For example, the one or more heat pipes 2224 may include a plurality of axially arranged heat pipes on a diameter centered at the center of the bore of the cylinder 2220. In a further example, one or more heat pipes 2224 can include an annular void in cylinder 2220. A heat pipe port 2226 may be used in some embodiments to supply, remove, or otherwise control the fluid in one or more heat pipes 2224. For example, the heat pipe port 2226 includes valves, regulators, orifices, any other suitable feature or device, or any combination thereof, the characteristics of one or more heat pipes 2224 or the fluid contained therein. Can be controlled. In some embodiments, the coolant passage 2222 and / or the coolant passage 2238 can directly contact (not shown) one or more heat pipes 2224 and can be relatively free from one or more heat pipes 2224. Can provide increased heat transfer. Although coolant passages 2222 and 2238 and one or more heat pipes 2224 are shown in FIG. 22, some embodiments (not shown in FIG. 22) include coolant passages and one or more heat pipes. Either can be included, and therefore need not include both. The use of coolant passages 2222 and 2238 and one or more heat pipes 2224 together may provide relatively improved heat transfer in some arrangements compared to any single use. . For example, heat may be transferred from the bore of the cylinder 2220 through the gap to one or more heat pipes 2224 that may transfer at least a portion of this heat to the coolant passages 2222 and / or. Or it may be transferred to the coolant in the coolant passage 2238 (eg, heat transfer may include conduction through a portion of the cylinder 2220).

  In some embodiments, fluid supplied to any of the ports 2250 can be used to cool the piston assembly 2210 or a portion thereof. For example, heat from the piston face of the piston assembly 2210 can be transported to the piston rod of the piston assembly 2210 and fluid supplied to any of the ports 2250 can cool the piston rod of the piston assembly 2210 by convection.

  In some embodiments, the hydrodynamic bearing may assist in cooling the piston assembly, cylinder, its components, any other suitable component of the piston engine, or any combination thereof. The bearing fluid can be supplied to a bearing element that can direct the bearing fluid to a suitable gap in the piston-cylinder assembly. As the bearing fluid flows through the gap, it may assist in cooling at least a portion of the piston-cylinder assembly. In some embodiments, the bearing fluid may flow through the gap substantially away from the combustion compartment, thus carrying heat away from the combustion compartment and thus reducing the temperature of one or more components of the piston engine. obtain. In some embodiments, convection of the bearing fluid through the piston engine gap may increase the effective heat transfer rate between the piston face and the piston assembly and / or another portion of the cylinder. In some embodiments, one or more heat pipes can be included in a piston assembly having bearing elements. The one or more heat pipes may assist in maintaining the bearing element or a portion of the bearing element approximately isothermal, which may assist in controlling thermal expansion and associated changes in clearance. In some embodiments, the use of one or more heat pipes, coolant passages, bearing elements, any other suitable component, or any combination thereof may be used for one or more components of the piston engine. By managing thermal deformation, it may help in maintaining or otherwise managing the gap.

(Cylinder liner)
In some embodiments, the clearance between the free piston and the cylinder can be controlled or otherwise managed. In some embodiments, a deformable cylinder liner can be used to adjust the clearance by adjusting the bore through which the piston assembly moves. In some embodiments, liner fluid can be used to apply pressure to a deformable cylinder liner that can deform based on a pressure difference between the faces of the cylinder liner. The liner fluid may comprise, for example, water, ethylene glycol, propylene glycol, oil, hydraulic fluid, fuel (eg, diesel fuel), any other suitable fluid, or any suitable combination thereof.

  FIG. 23 illustrates a cross-sectional view of an exemplary piston assembly 2310 and cylinder 2320 with a deformable cylinder liner 2330 according to some embodiments of the present disclosure. The inner surface of the deformable cylinder liner 2330 may define a bore in which the piston assembly 2310 or a portion thereof may translate along the axis 2350 at the center of the bore. A passage 2322 may be formed between the cylinder 2320 and the deformable cylinder liner 2330, in which liner fluid may be supplied and / or returned via the port 2324. A liner fluid controlled to a suitable pressure may impart a deforming force to the deformable cylinder liner 2330 and allow the bore to be adjusted accordingly. The gap 2360 between the bore and the piston assembly 2310 can thus be adjusted by the application of liner fluid at a suitable pressure. Increasing the pressure of the liner fluid (eg, by supplying liner fluid to the passage 2322 via one or more of the ports 2324) can reduce the bore and gap 2360 while the pressure of the liner fluid Reducing the bore and gap 2360 (eg, by removing liner fluid from the passage 2322 via one or more of the ports 2324). FIG. 24 illustrates a cross-sectional view of the exemplary piston assembly 2310 and cylinder 2320 of FIG. 23 with a deformable cylinder liner 2330 undergoing deformation, according to some embodiments of the present disclosure. The liner fluid pressure is greater in the passage 2322 relative to that shown in FIG. 23, as shown in FIG. 24, and thus the gap 2460 is relatively smaller than the gap 2360.

  FIG. 25 illustrates a cross-sectional view of an exemplary piston assembly 2510 and cylinder 2520 with a compartmentalized deformable cylinder liner 2530 according to some embodiments of the present disclosure. The inner surface of the deformable cylinder liner 2530 may define a bore in which the piston assembly 2510 or a portion thereof may translate along the axis 2550 at the center of the bore. Passages 2522 and 2523 can be formed between the cylinder 2520 and the deformable cylinder liner 2530 and can be separated by a seal 2532. Liner fluid may be supplied to and / or returned from passages 2522 and 2523 via ports 2524 and 2525, respectively, and may be isolated from each other, although not necessary. A liner fluid controlled to a suitable pressure imparts a deforming force to the deformable cylinder liner 2530, allowing the bore in each compartment (ie, the portion of the bore corresponding to passage 2522 or 2523) to be adjusted accordingly. Can be. In some embodiments, the pressure of the liner fluid is at least partially within a suitable compartment of the bore, as deformation of the deformable cylinder liner 2530 can depend on the differential pressure between the liner fluid and the bore. It can be controlled based on pressure. The gap 2560 between the bore and the piston assembly 2510 can thus be adjusted by the application of liner fluid at a suitable pressure. The gap can vary in the axial direction (ie, parallel to axis 2550) because the gap corresponding to each of passages 2522 and 2523 can be adjusted independently. For example, in some embodiments, as piston 2512 travels through a section of deformable cylinder liner 2530, the clearance can be adjusted in that section. Increasing the pressure of the liner fluid can be one or more (eg, by supplying liner fluid to passages 2522 and / or 2523 via one or more of the respective ports 2524 and / or 2525). Reducing the pressure of the liner fluid (e.g., via one or more of the respective ports 2524 and / or 2525 through the passageway 2522 and (Or by removing from 2523) may enlarge the bore and gap 2560 at one or more locations.

  FIG. 26 illustrates a cross-sectional view of an exemplary piston engine 2600 with a deformable cylinder liner 2630 according to some embodiments of the present disclosure. A passage 2622 may be formed between the cylinder 2620 and the deformable cylinder liner 2630 in which liner fluid may be supplied and / or returned via the port 2624. A liner fluid controlled to a suitable pressure may impart a deforming force to the deformable cylinder liner 2630 and allow the bore to be adjusted accordingly. In the illustrated embodiment, the port 2626 (eg, that provides fuel and / or air or can receive exhaust) is located outside of the deformable cylinder liner 2630 and is a port in the deformable cylinder liner 2630 or others. The need for an opening can be eliminated. Adjustment of the clearance between the piston assembly 2610 and the deformable cylinder liner 2630 can be accomplished by adjusting the pressure of the liner fluid in the passage 2622.

  In some embodiments, the flow of liner fluid can be used to provide cooling for the deformable cylinder liner. For example, pressure-controlled and flow-controlled liner fluid can be used to provide convective heat transfer from a deformable cylinder liner (eg, near the combustion compartment) to the liner fluid. Cooling with the liner fluid can be used in conjunction with or instead of cooling with the use of coolant passages and / or heat pipes (eg, as shown in FIG. 22).

  FIG. 27 shows a cross-sectional view (perpendicular to the bore axis) of a portion of an exemplary piston engine 2700 with local coolant passages 2752 and 2754 according to some embodiments of the present disclosure. The cylinder 2720 of the piston engine 2700 may include one or more plenums 2722 that may be coupled to one or more throttles 2724 and one or more throttles 2726. In some embodiments, a throttled fluid may flow from one or more plenums 2722 through one or more throttles 2724 into a coolant passage 2752 that is configured to cool the region 2732. (E.g., as indicated by the illustrative arrow in coolant passage 2752). In some embodiments, the throttled fluid may flow from one or more plenums 2722 through one or more throttles 2726 into a coolant passage 2754 configured to cool the region 2734. (E.g., as indicated by the illustrative arrow in coolant passage 2754). One or more throttles 2724 and 2726 may each include a fixed flow restriction orifice, an adjustable flow restriction orifice, a controllable throttle valve, any other suitable fluid restriction feature, or any combination thereof. One or more throttles 2724 and 2726 may cause a reduction in the pressure of the throttled fluid and may also cause a reduction in the temperature and / or enthalpy of the throttled fluid. The decrease in fluid temperature and / or enthalpy may improve heat transfer from the bore of cylinder 2720 (eg, the illustrated bore configured to house piston assembly 2710). In some embodiments, the coolant passages 2752 and 2754 include tubular conduits, manifolds, or other flow directing components that allow the flow of throttled fluid from one or more throttles 2724 and 2726 to the cylinder 2720. It can be provided to a local spatial region and then fluid can be returned to a fluid control system (eg, which can include a return line and a reservoir). Piston engine 2700 may include any suitable number of plenums 2722 that are not required, but can be interconnected. For example, the plenum 2722 may include a plurality of plenums, each of which is separately controllable to provide selectable cooling to the local spatial region of the cylinder 2720. In a further example, the plenum 2722 may include a single plenum that may be coupled to multiple throttles and provide selectable cooling to a local spatial region of the cylinder 2720. The plurality of throttles may be separately controllable or otherwise have unique flow restriction characteristics to control cooling of one or more local spatial regions of cylinder 2720. In some embodiments, cooling of the cylinder 2720 using a throttled fluid may allow control of cylinder temperature and the clearance between the cylinder 2720 and the piston assembly 2710. In some embodiments, direct or indirect measurements of bore geometry (eg, size, shape, or both) are used by the control system to control cooling by the local coolant passages 2752 and 2754. obtain. For example, higher operating temperatures can be expected near the combustion section 2730 near the TDC, and increased cooling can be provided in region 2732 to limit the temperature field. In further examples, in some situations, reduced cooling may be provided in region 2732 to enlarge the corresponding bore and associated gap. The increase or decrease in cooling can be any other suitable by adjusting the flow of the throttled fluid by adjusting the temperature of the throttled fluid by increasing or decreasing the throttle action of the throttle. May be provided by minor adjustments or by any combination thereof. The throttled fluid can include any suitable coolant fluid, which can be a liquid or a gas. For example, the throttled fluid can include ethylene glycol, propylene glycol, water, alcohol, air, any other suitable fluid, or any combination thereof (eg, ethylene glycol diluted with water). The cylinder 2720 may include any suitable port 2770 for supplying or removing fluid (eg, air, fuel, exhaust, or combinations thereof) to a suitable section of the piston engine 2700.

  FIG. 28 shows a cross-sectional view (parallel to the bore axis) of a portion of an exemplary piston engine 2800 with a local coolant passage 2826 according to some embodiments of the present disclosure. Piston engine 2800 may include a cylinder 2820 having a plenum 2822. The cylinder 2820 may include a bore configured to house a piston assembly 2810 configured to move substantially linearly in a direction substantially parallel to the outer product of the vectors 2850 and 2860. . Although shown in FIG. 28 as an annular plenum, the plenum 2822 may include any suitable conduit shape arranged to provide any suitable flow path. The coolant may flow through the throttle 2824 and into the local coolant passage 2826 to cool the corresponding spatial region of the cylinder 2820. In the illustrated embodiment, the coolant flows radially inward from the throttle 2824 (as indicated by the four arrows pointing radially inward in FIG. 28), and then vector 2850 and vector 2860 Flows in the direction given by the outer product (2850 × 2860 in the plane direction of FIG. 28). The coolant return flow path is not shown in FIG. 28 but may include radial, axial, or both flow paths. In some embodiments, the throttle 2824 can generate a fluid jet in the local fluid passage 2826 that impinges on the spatial region of the cylinder 2820 and causes relatively increased convective heat transfer to that region. Can bring. Although shown in FIG. 28 as having four symmetric local coolant passages 2826, the piston engine 2800 is arranged in any suitable axial location in any suitable symmetric or asymmetric configuration, and any suitable Any suitable number of local coolant passages may be included that are coupled to any number of plenums or other coolant sources.

  FIG. 29 illustrates a cross-sectional view of a portion of an exemplary piston engine 2900 with a local heat source, including electric heaters 2922, 2923, 2924, 2925, 2926, and 2927, according to some embodiments of the present disclosure. Show. Each of the electrical heaters 2922, 2923, 2924, 2925, 2926, and 2927 includes one or more electrical conductors used by a suitable control system, and the voltage, current, power, or them supplied to the heater Can be controlled. For example, electric heaters 2922 and 2923 may be used separately or in conjunction to provide heating to region 2932 near combustion compartment 2930 (eg, to increase the clearance between cylinder 2920 and piston assembly 2910). ). In a further example, electric heaters 2924, 2925, 2926, and 2927 can be used to heat corresponding regions 2934 and 2936. A local heat source such as an electric heater may be used to provide relatively fast thermal control of one or more spatial regions of the cylinder. In some embodiments, direct or indirect measurements of bore geometry (eg, size, shape, or both) can be used by the control system to control the local heat source. For example, each of the electric heaters 2922, 2923, 2924, 2925, 2926, and 2927 can be detected temperature, pressure, gap, blow-by characteristics, work interaction, any other suitable indicator, or any of those In response to the combination, it may be separately controllable by the control system. The cylinder 2920 may include any suitable port 2970 for supplying or removing fluid (eg, air, fuel, exhaust, or combinations thereof) to a suitable compartment of the piston engine 2900.

  FIG. 30 illustrates a cross-sectional view of a portion of an exemplary piston engine 3000 that includes fluid passages 3022 and 3024 that may be used for heating, cooling, or both, according to some embodiments of the present disclosure. In some embodiments, heating fluid, cooling fluid, or both may be supplied to fluid passages 3022 and 3024 that may be interconnected, although not necessary. For example, fluid may be supplied to and removed from fluid passages 3022 and 3024 (eg, for an annular fluid passage having supply and return ports), as indicated by the four arrows in FIG. In some embodiments, fluid passages 3022 and 3024 can be local heating sources. For example, fluid passages 3022 and 3024 can be separately controlled and can provide heating to respective regions 3032 and 3034. The fluid passageway 3022 or 3024 can include, for example, a preheated coolant, an exhaust fluid (eg, a hot combustion product from a combustion section), any other suitable heated fluid, or any combination thereof. Heat can be provided by acting as a conduit for the heating fluid. In some embodiments, fluid passages 3022 and 3024 can be used for both heating and cooling of the spatial region of cylinder 3020. For example, heated fluid may be supplied to the fluid passageway 3022 and increase the temperature of the region 3032 (eg, to increase the bore diameter and gap), while cooling fluid is supplied to the fluid passageway 3024 and the temperature of the region 3034. Can be reduced (eg, to reduce bore diameter and clearance). In a further example, heated fluid or coolant may be supplied to the fluid passageway 3022 as determined by the control system. The cylinder 3020 may include any suitable port 3070 for supplying or removing fluid (eg, air, fuel, exhaust, or combinations thereof) to a suitable section of the piston engine 3000.

  In some embodiments, the cylinder may be configured to undergo thermal deformation or changes corresponding to the controlled temperature of the cylinder, such as those described in the context of FIGS. 22 and 27-30, for example. The controlled temperature or change thereof may correspond to the local spatial region of the cylinder. The use of a coolant, heated fluid, squeezed fluid, electrical resistance heater, any other suitable component or feature to control temperature, or any combination thereof can be controlled by the control system, for example It may be possible to control one or more characteristics of the piston engine, such as a clearance.

(Combination of approaches)
In some embodiments, two or more of the aforementioned approaches can be combined. Self-aligning features, fluid bearings, heat pipes, coolant passages, deformable cylinder liners, and any other suitable components or features may be suitably combined in implementing a piston engine in accordance with the present disclosure.

  For example, FIG. 31 shows a perspective view of a portion of an exemplary piston assembly 3100 having a seal 3104, a hydrodynamic bearing element 3108, and a self-aligning feature 3106, according to some embodiments of the present disclosure. The piston assembly 3100 may include a piston face 3102, a seal 3104, a self-aligning feature 3106, a hydrodynamic bearing element 3108, any other suitable component (not shown), or any combination thereof. In some embodiments (as shown), the self-aligning feature 3106 can be part of the seal 3104. For example, the seal 3104 can include a self-aligning feature 3106, which can be a machined step in the bearing element or other suitable feature. In some embodiments (not shown), the self-aligning feature 3106 can be part of the piston face 3102. For example, the self-aligning feature 3106 can be a step, one or more slotted pockets, a tapered portion, or other feature included within the piston assembly 3100. Gas supplied from any suitable fluid source may be distributed into the piston assembly 3100 via an internal fluid passage (not shown) and then flow through any suitable portion of the fluid bearing element 3108. (In FIG. 31, shown as porous, any suitable bearing element may be used).

  In a further example, FIG. 32 illustrates a piston assembly 3210 having a bearing element 3214, a heat pipe 3250, and a self-aligning feature 3212, a deformable cylinder liner 3232, and a coolant passage according to some embodiments of the present disclosure. A cross-sectional view of an exemplary piston engine 3200 having a cylinder 3230 with 3236 is shown. The piston assembly 3210 can be configured to translate within a bore created by the deformable cylinder liner 3232 with a gap 3260. Application of a liner fluid controlled to a suitable pressure can be supplied to the passage 3234 via the port 3233 to adjust the gap 3260. Bearing fluid may be supplied to passageway 3218 and flow from bearing element 3214 into gap 3260 to assist in aligning piston assembly 3210 within the bore. Self-aligning feature 3212 may assist in aligning piston assembly 3210 within the alignment bore. A suitable coolant may be supplied to the coolant passage 3236 in the cylinder 3230 to remove heat from the cylinder 3230 or a portion thereof. A heat pipe 3250 having a fill port 3282 may assist in transferring heat from the piston face 3202 to another portion of the piston assembly 3210. Port 3270 may be used to supply oxidant and / or fuel, supply and / or remove drive gas, or remove exhaust from the cylinder compartment.

  In some embodiments, a combination of one or more approaches may require one or more additional considerations. For example, in some embodiments, the piston assembly is configured to provide a self-aligning feature and bearing fluid to the gap that is configured to provide a self-aligning force using blow-by gas. Bearing elements. The self-aligning feature may therefore require that some blow-by gas flows along the gap and provides self-aligning force. Under some conditions, the flow of blow-by gas in the gap can affect the performance of the bearing element by changing the flow pattern of the bearing fluid in the gap. Thus, in some embodiments having a bearing element behind the self-aligning feature (relative to the combustion compartment), the blow-by gas has crossed a portion of the gap adjacent to the self-aligning feature, but the bearing It can be routed away from the gap before flowing into a portion of the gap adjacent to the element. Further, in some arrangements, the bearing element may include self-aligning features and a collection of holes for directing bearing fluid that may extend to the piston face. Thus, in some such embodiments, blow-by gas routing away from the gap need not be used. The foregoing embodiments can optionally be applied to a gas driven section in addition to or instead of the combustion section.

(Control of gaps and / or other properties)
In some embodiments, one or more aspects of the operation of the piston engine are controlled or otherwise modified to affect temperature, clearance, any other suitable characteristic of the piston engine, or any combination thereof. Can be managed. In some embodiments, control of piston engine temperature, pressure, or other suitable characteristics may assist in managing piston engine clearance. For example, relatively large temperature differences can cause deformations such as expansion of some components of the piston engine that can affect the clearance. Control of the temperature difference and / or temperature field can assist in reducing deformation and thus assist in managing gaps. Gap management may include management of any other suitable property that may affect the gap.

  FIG. 33 is a block diagram of an exemplary control arrangement 3300 for a piston engine 3340 according to some embodiments of the present disclosure. Control system 3310 may communicate with one or more sensors 3330 coupled to piston engine 3340. The control system 3310 can be configured to communicate with an auxiliary system 3320 that can be used to adjust the aspect or characteristics of the piston engine 3340. In some embodiments, the control system 3310 can be configured to interact with the user via the user interface system 3350.

  The control system 3310 may include a processing device 3312, a communication interface 3314, a sensor interface 3316, a control interface 3318, any other suitable component or module, or any combination thereof. The control system 3310 may be implemented at least in part in one or more computers, terminals, control stations, handheld devices, modules, any other suitable interface device, or any combination thereof. In some embodiments, the components of the control system 3310 can be communicatively coupled via a communication bus 3311 as shown in FIG. The processing equipment 3312 may process information regarding the piston engine 3340 as received from the sensor 3330 by the sensor interface 3316, such as a processor (eg, central processing unit), cache, random access memory (RAM), read only memory (ROM). ), Any other suitable component, or any combination thereof. The sensor interface 3316 may include a power source for supplying power to the sensor 3330, signal conditioner, signal preprocessor, any other suitable component, or any combination thereof. For example, sensor interface 3316 may include filters, amplifiers, samplers, and analog / digital converters for conditioning and preprocessing the signal from sensor 3330. The sensor interface 3316 uses a wired connection (eg, using an IEEE 802.3 Ethernet or Universal Serial Bus interface), wireless coupling (eg, IEEE 802.11 “Wi-Fi” or Bluetooth®). ), Communication coupling 3319, which may be optical coupling, inductive coupling, any other suitable coupling, or any combination thereof. The control system 3310, and more specifically the processing equipment 3312, can be configured to provide control of the piston engine 3340 over an associated time scale. For example, one or more temperature changes may be controllable in response to one or more detected engine operating parameters, and control may be performed on a time scale associated with piston engine operation (e.g., overheating and / or Or a response fast enough to prevent component failure).

  Sensor 3330 may include any suitable type of sensor that may be configured to sense any suitable characteristic or condition of piston engine 3340. In some embodiments, the sensors may include one or more sensors configured to sense certain conditions and / or characteristics of the auxiliary system 3320 system. In some embodiments, the sensor 3330 is a temperature sensor (e.g., configured to sense the temperature of components of the piston engine 3340, fluid introduced into or recovered from the piston engine 3340, or both). , Thermocouple, resistance temperature detector, thermistor, or optical temperature sensor). In some embodiments, the sensor 3330 may be a pressure in a section of the piston engine 3340 (eg, a combustion section, or a gas driven section), a fluid introduced into or recovered from the piston engine 3340, or both pressures. One or more pressure sensors (eg, piezoelectric pressure transducers) configured to sense In some embodiments, sensor 3330 is configured to sense a force in piston engine 3340 such as tension, compression force, or shear force (e.g., may indicate frictional force or other related force information). One or more force sensors (eg, a piezoelectric power converter) may be included. In some embodiments, sensor 3330 may include voltage, current, work output and / or input (eg, current multiplied by voltage), piston engine 3340 and / or any other suitable electrical characteristic of auxiliary system 3320. Or may include one or more current and / or voltage sensors (eg, an ammeter and / or voltmeter coupled to the LEM of the piston engine 3340) configured to sense any combination thereof.

  The control interface 3318 can be a wired connection (eg, using an IEEE 802.3 Ethernet or universal serial bus interface), wireless coupling (eg, IEEE 802...) To communicate with one or more of the auxiliary systems 3320. 11 “Wi-Fi”, Bluetooth®, or other RF communication protocols), optical coupling, inductive coupling, any other suitable coupling, or any combination thereof. In some embodiments, the control interface 3318 may include a digital / analog converter to provide analog control signals to some or all of the auxiliary system 3320.

  The auxiliary system 3320 may include a cooling system 3322, a pressure control system 3324, a gas drive control system 3326, and / or any other suitable control system 3328. The cooling / heating system 3322 includes a pump, fluid reservoir, pressure regulator, bypass, radiator, fluid conduit, power circuit (eg, for an electrical heater), any other suitable component, or any combination thereof. , Cooling, heating, or both may be provided to the piston engine 3340. The pressure control system 3324 includes a pump, compressor, fluid reservoir, pressure regulator, fluid conduit, any other suitable component, or any combination thereof and supplies pressure-controlled fluid to the piston engine 3340 ( And optionally accept). The gas drive control system 3326 includes a compressor, gas reservoir, pressure regulator, fluid conduit, any other suitable component, or any combination thereof, and supplies drive gas to the piston engine 3340 (and optionally Get). In some embodiments, the other system 3328 may include a valve system, such as a cam actuation system or a solenoid system, for example, to supply oxidant and / or fuel to the piston engine 3340.

  User interface 3315 uses a wired connection (eg, IEEE 802.3 Ethernet, or a universal serial bus interface, tip-ring-seal RCA type connection to communicate with one or more of user interface systems 3350. Wireless coupling (eg, using IEEE 802.11 “Wi-Fi”, infrared, or Bluetooth®), optical coupling, inductive coupling, any other suitable coupling, or any combination thereof Can be included. User interface system 3350 may include display 3352, keyboard 3354, mouse 3356, audio device 3358, any other suitable user interface device, or any combination thereof. Display 3352 can be, for example, any other suitable display screen that can provide a user with a cathode ray tube screen, a liquid crystal display screen, a light emitting diode display screen, a plasma display screen, a graphic, text, image, or other visual display, or It may include a display screen such as any combination of the screens. In some embodiments, the display 3352 may include a touch screen that may provide tactile interaction with the user, for example, by presenting one or more soft commands on the display screen. Display 3352 may be any suitable information regarding piston engine 3340 (eg, a time series of characteristics of piston engine 3340), control system 3310, auxiliary system 3320, user interface system 3350, any other suitable information, or any Their combination can be displayed. Keyboard 3354 may include a QWERTY keyboard, a numeric keypad, any other suitable collection of hard command buttons, or any combination thereof. Mouse 3356 may include any suitable pointing device that can control a cursor or icon on a graphical user interface displayed on the display screen. Mouse 3356 may include a handheld device (eg, movable in two or three dimensions), a touchpad, any other suitable pointing device, or any combination thereof. Audio device 3358 may include a microphone, speakers, headphones, any other suitable device for providing and / or receiving audio signals, or any combination thereof. For example, the audio device 3358 may include a microphone and the processing equipment 3312 may process voice commands received via the user interface 3315 that result from the user speaking to the microphone.

  In some embodiments, the control system 3310 can be configured to provide manual control by receiving one or more user inputs. For example, in some embodiments, the control system 3310 overrides automatic control settings based on sensor feedback and sends control signals to the auxiliary system 3320 based on one or more user inputs to the user interface system 3350. It can be put out. In further examples, the user may enter a setpoint value for one or more control variables (eg, temperature, pressure, flow rate, work input / output, or other variables), and control system 3310 may A control algorithm may be executed based on the point value.

  In some embodiments, operational characteristics (ie, a set of desired characteristic values for piston engine 3340 or auxiliary system 3320) may be pre-defined by the manufacturer, user, or both. For example, certain operating characteristics can be stored in the memory of the processing equipment 3312 and accessed to provide one or more control signals. In some embodiments, one or more of the operating characteristics may be changed by the user. Array 3300 can be used to maintain, adjust, or otherwise manage their operational characteristics.

  FIG. 34 is a flow diagram 3400 of illustrative steps for adjusting piston engine clearances according to some embodiments of the present disclosure.

  Step 3402 may include detecting a gap indicator using sensor 3330. The gap indicator can be temperature (eg, coolant, heated fluid, cylinder, piston, or other component, or part thereof) temperature, pressure, force, distance (eg, gap), work interaction (eg, electromagnetic work Output), material (eg, blowby or its characteristics), any other suitable detectable characteristic, or any combination thereof. Sensor interface 3316 may receive, adjust, and / or pre-process gap indicators from sensor 3330 and output sensor signals to processing device 3312. In some embodiments, the clearance indicator may be stored and correlated with one or more operating conditions of the piston engine. For example, cylinder temperature can be correlated with fuel flow and stored as a mathematical formula or table. Thus, step 3402 may include detecting one or more operating conditions of the piston engine and recalling stored cylinder temperature values that may be used for further processing.

  Step 3404 may include the processing device 3312 determining a control response based at least in part on the detected gap indicator of step 3402. Processing equipment 3312 may receive sensor signals from sensor interface 3316 and perform one or more processing functions on the sensor signals. The processing function can input sensor signal values into equations or other mathematical expressions, use sensor signal values in a lookup table or other database, any other suitable process, or any combination thereof. May be included. Processing device 3312 may determine a control response based on the output of one or more processing functions. For example, the calculated value can be compared to a predefined threshold to determine a suitable control response. In a further example, one or more calculated values can be input to a control algorithm (eg, a proportional-integral-derivative (PID) control algorithm), and one or more control signal values can be determined.

  Step 3406 allows the processing equipment 3312 to provide a control signal to one or more of the auxiliary systems 3320 based at least in part on the determined control response of step 3404 using the control interface 3318. Can be included. The control signal can be an electrical signal (eg, using a wired cable), an electromagnetic signal (eg, using an IEEE 802.11 “Wi-Fi” or Bluetooth® receiver / transmitter), an optical signal (eg, Analog signals, digital signals, or combinations thereof (eg, digital timing), which may be provided as fiber optic cables), inductive signals (eg, using suitable conductive coils), or other suitable signal types Analog signal with signal).

  Step 3408 may include one or more of the auxiliary systems 3320 that received the control signal in step 3406 adjusting the clearance or other characteristics of the piston engine 3340. One or more of the auxiliary systems 3320 may adjust pressure, temperature, flow rate, flow path, current, voltage, power, make any other suitable adjustments based on the provided control signals, or any You can make those combinations. As indicated by the dotted arrows in FIG. 34, some or all of steps 3402-3408 may be repeated to allow closed loop control. In some embodiments, an open loop approach may be used, in which case step 3402 may be omitted (but not required) and steps 3404-3408 are performed without looping.

  In some arrangements, the temperature field of the cylinder and / or piston assembly of the piston engine or the fluid contained therein can be a primary and convenient indicator of the gap, so that the temperature field can thus adjust the gap. It can be actively adjusted. In an illustrative example, step 3402 may include detecting a temperature, such as, for example, a cylinder temperature or a coolant temperature (eg, of a coolant provided to a coolant passage of a cylinder of a piston engine). Step 3404 may include adjusting the temperature field and determining how to maintain or otherwise manage the gap, while step 3406 may include providing a corresponding control signal to the appropriate auxiliary system. For example, the cylinder temperature can be increased by reducing the coolant flow rate, which can enlarge the gap via thermal expansion. In a further example, the cylinder temperature can be lowered by increasing the coolant flow rate, which can reduce the gap via thermal contraction. In a further embodiment, the flow rate of coolant or heated fluid in more than one set of fluid passages may be adjusted to control the temperature field of the zone of the cylinder (see, eg, FIG. 22). Referring to the previous embodiment, the coolant or heated fluid flow rate is based on the control signal of step 3406, for example, to control the flow control valve, pump rotational speed, bypass flow control valve, pressure regulator, flow rate, etc. It can be adjusted by adjusting any other suitable control device, or any combination thereof. In a further illustrative example, step 3402 may include detecting a temperature, such as, for example, the temperature of a heat pipe in a cylinder of a piston engine (eg, the temperature of the heat pipe or the heat pipe fluid therein). Step 3404 may include adjusting the temperature field and determining how to maintain or otherwise manage the gap, while step 3406 may include providing a corresponding control signal to the appropriate auxiliary system. For example, the heat pipe temperature can be increased by increasing the pressure of the fluid in the heat pipe (eg, by adding fluid to the heat pipe or reducing the volume of the heat pipe), which Can be enlarged. In a further example, the heat pipe temperature can be lowered by reducing the heat pipe pressure (e.g., by removing fluid from the heat pipe or increasing the volume of the heat pipe), The gap can be reduced. Referring to the foregoing embodiment, the characteristics of the fluid in the heat pipe (eg, having a fluid port or other adjustable feature) can be determined based on the control signal of step 3406, eg, a flow control valve, pressure regulator, It may be adjusted by adjusting a check valve, any other suitable control device for controlling the heat pipe pressure, and a suitable fluid port included in the heat pipe, or any combination thereof.

  FIG. 35 is a flowchart 3500 of illustrative steps for adjusting one or more characteristics of a piston engine, according to some embodiments of the present disclosure.

  In some embodiments, the gap indicator can be detected using sensor 3330. Sensor interface 3316 may receive the raw signal from sensor 3330 and provide the sensor signal to processing device 3312. For example, step 3502 detects the cylinder temperature of the piston engine 3340 using a temperature sensor, such as a thermocouple, located in contact with or near a portion of the cylinder (eg, near the combustion section). Can be included. In some situations, an increase in cylinder temperature may indicate insufficient cooling, which can affect the gap. In a further embodiment, step 3504 may be performed by using a temperature sensor, such as a thermocouple, located in contact with or near a portion of the piston assembly (eg, near the piston face). Detecting. In some situations, an increase in piston temperature may indicate insufficient cooling that can affect the gap. In a further embodiment, step 3506 uses a temperature sensor such as a thermocouple (eg, inserted into the fluid conduit using a suitable measurement port) positioned in contact with or near the fluid. Detecting the temperature of the fluid of the piston engine 3340 (eg, coolant, heated fluid, or exhaust that can be supplied to and recovered from the piston engine 3340). For example, in some situations, an increase in coolant temperature may indicate insufficient cooling that can affect the gap. In a further example, step 3507 includes a pressure sensor (eg, inserted into the conduit using a suitable measurement port), such as a piezoelectric transducer, positioned in contact with or near the coolant. May be used to detect the pressure of the combustion section, gas drive section, gap, coolant, heated fluid, any other fluid of the piston engine 3340, or any combination thereof. In a further embodiment, step 3508 uses a force sensor such as a thermocouple or other piezoelectric transducer and / or a temperature sensor positioned in contact with or near the component interface to configure piston engine 3340. It may include detecting friction between possible. In some situations, increased friction effects (eg, frictional force, or frictional heat of generation) may indicate insufficient clearance. In a further example, step 3509 may include detecting one or more characteristics of the clearance of piston engine 3340. One or more characteristics include gap thickness (eg, using proximity sensors such as inductive sensors), gap asymmetry (eg, using multiple proximity sensors such as inductive sensors), blow-by temperature ( (E.g., using a temperature sensor), blow-by pressure (e.g., using a pressure sensor), blow-by composition (e.g., using a gas sensor such as a light absorption sensor), and other suitable characteristics, or any A combination thereof. In a further embodiment, step 3510 includes an average effective pressure (MEP, such as an electromagnetic sensor (eg, voltmeter, ammeter, or power meter), pressure transducer (eg, illustrated MEP, axial MEP, and / or friction MEP). ) To detect the pressure), or other suitable sensor to detect work interaction of the piston engine 3340 and provide an indication of the clearance. In some situations, decreased work output or increased work input requirements may indicate insufficient and / or excessive clearance.

  Step 3512 may include the processing device 3312 determining a control response based at least in part on some or all of the detected gap indicators of steps 3502, 3504, 3506, 3508, and 3510. Processing device 3312 may receive sensor signals from sensor interface 3316 and perform one or more processing functions on the sensor signals. The processing function can input sensor signal values into equations or other mathematical expressions, use sensor signal values in a lookup table or other database, any other suitable process, or any combination thereof. May be included. Processing device 3312 may determine a control response based on the output of one or more processing functions. For example, the calculated value can be compared to a predefined threshold to determine a suitable control response. In further embodiments, one or more calculated values can be input to a control algorithm (eg, a PID control algorithm), and one or more control signal values can be determined.

  Step 3514 allows the processing device 3312 to provide a control signal to one or more of the auxiliary systems 3320 based at least in part on the determined control response of Step 3512 using the control interface 3318. Can be included. The control signal can be an electrical signal (eg, using a wired cable), an electromagnetic signal (eg, using an IEEE 802.11 “Wi-Fi” or Bluetooth® receiver / transmitter), an optical signal (eg, Analog signals, digital signals, or combinations thereof (eg, digital timing), which may be provided as fiber optic cables), inductive signals (eg, using suitable conductive coils), or other suitable signal types Analog signal with signal).

  In some embodiments, the control signal of step 3514 may be received by one or more of the auxiliary systems 3320 that may adjust the clearance or other characteristics of the piston engine 3340. For example, as indicated by step 3516, the control signal of step 3514 may be received by a cooling / heating system 3322 that may adjust the temperature of the coolant or heating fluid. The cooling / heating system 3322 may include a thermostat or other temperature adjustment device that may adjust the coolant or heating fluid temperature provided to the piston engine 3340 in step 3516 according to the control signal. In a further example, step 3516 may include a cooling / heating system 3322 that adjusts one or more throttle characteristics and controls the temperature of the throttled fluid. In a further example, as indicated by step 3518, the control signal of step 3514 may be received by a cooling / heating system 3322 that may adjust the flow rate of the coolant or heating fluid. The cooling / heating system 3322 may include a flow regulator (eg, a throttle valve or orifice) that may adjust the flow rate of coolant or heating fluid provided to the piston engine 3340 in step 3518 according to the control signal. In a further example, step 3518 may include a cooling / heating system 3322 that adjusts one or more throttle characteristics and controls the flow rate of the throttled fluid. In a further example, as indicated by step 3520, the control signal of step 3514 may be received by a cooling / heating system 3322 that may adjust the flow path of the coolant or heating fluid in step 3520. The cooling / heating system 3322 includes one or more valves that may direct and control the flow rate of coolant or heated fluid provided to and / or from one or more fluid passages to the piston engine 3340 according to control signals. A throttle or other flow control device may be included. In a further example, as indicated by step 3522, the control signal of step 3514 may be received by a pressure control system 3324 that may adjust one or more characteristics of the heat pipe in step 3522. The pressure control system 3324 may include one or more valves and a fluid reservoir, and may adjust the pressure of the fluid in the heat pipe of the piston engine 3340 according to the control signal (eg, supply fluid to or from the heat pipe). By removing from). In a further embodiment, as indicated by step 3524, the control signal of step 3514 is received by a pressure control system 3324 that may adjust the pressure and / or flow rate of the liner fluid to the deformable cylinder liner of the piston engine 3340. obtain. The pressure control system 3324 may include one or more valves, pumps, and fluid reservoirs, and in accordance with the control signals, in step 3524, the pressure and / or flow rate of the liner fluid, and hence the deformation of the deformable cylinder liner of the piston engine 3340. Can be adjusted (eg, by increasing or decreasing the pressure in the liner passage). In a further example, the control signal of step 3514, indicated by step 3526, may be received by another system 3328 that may adjust one or more characteristics of the piston engine 3340. Other systems 3328 may include any suitable components and may achieve adjustment of one or more characteristics of piston engine 3340 at step 3526 based at least in part on the control signal. For example, other systems 3328 may include electronics configured to provide power to one or more electrical resistance heaters embedded within piston engine 3340, and step 3526 may include electrical resistance heaters. Adjusting the voltage, current, or both supplied can be included.

    Any of the illustrative steps in flowcharts 3400-3500 may be combined, omitted, rearranged, or otherwise modified in combination with other steps in accordance with this disclosure.

    The foregoing is merely illustrative of the principles of the present disclosure and various modifications can be made by those skilled in the art without departing from the scope of the present disclosure. The foregoing described embodiments are presented for purposes of illustration and not limitation. The present disclosure can also take many forms other than those explicitly described herein. Therefore, it should be emphasized that this disclosure is not limited to the explicitly disclosed methods, systems, and apparatus, but is intended to include variations and modifications thereof that are within the spirit of the following claims. .

In some embodiments, the clearance between the coaxial piston assembly and the cylinder of the piston engine can be controlled. For example, at least one indicator, such as gap temperature, pressure, work interaction, and / or other suitable indicator, may be detected using one or more sensors. The control response may be determined by the processing equipment based at least in part on the indicator. The processing equipment may use the control interface to provide a control signal to at least one auxiliary system of the piston engine based at least in part on the control response. The at least one auxiliary system may adjust the gap based at least in part on the control signal.
The present invention further provides, for example:
(Item 1)
An assembly,
A cylinder having a bore and a compartment capable of containing fluid;
A piston assembly axially translatable along an axis of the bore, the piston assembly comprising a piston face;
At least one bearing element configured to provide a bearing fluid flow to a gap formed between the piston assembly and the cylinder;
An assembly.
(Item 2)
The bearing element is attached to the piston assembly, the piston assembly further comprising a feed passage, wherein the feed passage receives the bearing fluid from a fluid source and provides the bearing fluid to the bearing element. The assembly according to item 1, wherein the assembly is configured as follows.
(Item 3)
The bearing element comprises a porous annular element, the porous annular element allowing the bearing fluid to flow radially outwardly from the feed passage through the pores into the gap. The assembly described in.
(Item 4)
The bearing element includes one or more radial holes, the one or more radial holes allowing the bearing fluid to flow radially outward from the feed passage into the gap. Item 3. The assembly according to item 2, wherein
(Item 5)
The bearing element is attached to the cylinder, the cylinder further comprising a feed passage, wherein the feed passage is configured to receive a bearing fluid from a fluid source and provide the bearing fluid to the bearing element. The assembly according to item 1, wherein:
(Item 6)
The bearing element of claim 1, wherein the bearing element comprises at least one of a graphite element, a metal element with machined features, a sintered metal element, a porous ceramic element, and a non-porous ceramic element. assembly.
(Item 7)
The assembly of claim 1, wherein the bearing fluid comprises air.
(Item 8)
The fluid contained within the compartment includes gas, and the piston assembly further comprises a feature or component that provides self-alignment using a flow of blow-by gas from the compartment. Assembly.
(Item 9)
The fluid contained within the compartment includes a gas, and the assembly is configured to route the flow of blow-by gas away from a portion of the gap adjacent to the bearing element. The assembly according to item 1, further comprising:
(Item 10)
The assembly of claim 1, wherein the fluid contained within the compartment comprises a gas and the piston assembly further comprises a labyrinth seal configured to affect the flow of blow-by gas.
(Item 11)
The assembly of claim 10, wherein the labyrinth seal comprises a plurality of circumferential grooves.
(Item 12)
The assembly of claim 1, wherein the flow of the bearing fluid is configured to form a fluid layer within the gap.
(Item 13)
13. An assembly according to item 12, wherein the fluid layer assists in alignment of the piston assembly about the axis of the bore.
(Item 14)
The assembly of claim 1, wherein the compartment comprises at least one of a combustion compartment and a gas driven compartment, and wherein the piston face is configured to contact the compartment.
(Item 15)
The assembly of claim 1, wherein the assembly is configured for oilless operation.
(Item 16)
An assembly configured to translate axially along an axis of a cylinder having a compartment capable of containing fluid, the assembly comprising:
A piston surface configured to contact the compartment;
At least one bearing element configured to provide an outward flow of bearing fluid to a surface of the assembly;
With
The assembly does not contact the cylinder.
(Item 17)
The assembly of claim 16, further comprising a feed passage, wherein the feed passage is configured to receive the bearing fluid from a fluid source and to provide the bearing fluid to the bearing element.
(Item 18)
The bearing element comprises a porous annular element, the porous annular element allowing the bearing fluid to flow radially outwardly from the feed passage to the surface of the assembly; Item 18. The assembly according to item 17.
(Item 19)
The bearing element includes one or more radial holes, which allow the bearing fluid to flow radially outward from the feed passage to the surface of the assembly. 18. An assembly according to item 17, wherein the assembly is configured to.
(Item 20)
The assembly of claim 16, wherein the fluid contained within the compartment comprises a gas, and the piston assembly further comprises a feature that provides self-alignment using a flow of blow-by gas from the compartment.
(Item 21)
The assembly of claim 16, wherein the fluid contained in the compartment comprises a gas, and the assembly further comprises a labyrinth seal configured to affect the flow of blow-by gas.
(Item 22)
The fluid contained within the compartment includes a gas, and the assembly includes one or more passages configured to route the flow of blow-by gas from the fluid compartment away from the surface of the assembly. The assembly according to item 16, further comprising:
(Item 23)
The assembly of claim 16, wherein the bearing fluid comprises air.
(Item 24)
17. An assembly according to item 16, wherein the compartment comprises at least one of a combustion compartment and a gas driven compartment, and the piston surface is configured to contact the compartment.
(Item 25)
The assembly of claim 16, wherein the assembly is configured for oilless operation.
(Item 26)
A cylinder of a piston engine,
A bore capable of retracting a piston, wherein the piston is movable along an axis of the bore; and
At least one bearing element configured to provide a flow of bearing fluid to the bore;
With
The piston is a cylinder that does not contact the cylinder.
(Item 27)
27. A cylinder according to item 26, further comprising a feed passage, wherein the feed passage is configured to receive the bearing fluid from a fluid source and to provide the bearing fluid to the bearing element.
(Item 28)
The bearing element comprises a porous annular element configured to allow the bearing fluid to flow radially inward from the feed passage through the pores to the bore. 28. The cylinder according to item 27.
(Item 29)
The bearing element comprises one or more radial holes, the one or more radial holes allowing the bearing fluid to flow radially inward from the feed passage to the bore. 28. The cylinder according to item 27.
(Item 30)
27. A cylinder according to item 26, wherein the cylinder is configured for an oil-free operation.

Claims (30)

An assembly,
A cylinder having a bore and a compartment capable of containing fluid;
A piston assembly axially translatable along an axis of the bore, the piston assembly comprising a piston face;
An assembly comprising: at least one bearing element configured to provide a flow of bearing fluid to a gap formed between the piston assembly and the cylinder.   The bearing element is attached to the piston assembly, the piston assembly further comprising a feed passage, wherein the feed passage receives the bearing fluid from a fluid source and provides the bearing fluid to the bearing element. The assembly of claim 1, wherein   The bearing element comprises a porous annular element, the porous annular element allowing the bearing fluid to flow radially outwardly from the feed passage into the gap. 3. The assembly according to 2.   The bearing element includes one or more radial holes, the one or more radial holes allowing the bearing fluid to flow radially outward from the feed passage into the gap. The assembly of claim 2, wherein the assembly is configured as follows.   The bearing element is attached to the cylinder, the cylinder further comprising a feed passage, wherein the feed passage is configured to receive a bearing fluid from a fluid source and provide the bearing fluid to the bearing element. The assembly of claim 1.   2. The bearing element of claim 1, wherein the bearing element comprises at least one of a graphite element, a metal element with machined features, a sintered metal element, a porous ceramic element, and a non-porous ceramic element. Assembly.   The assembly of claim 1, wherein the bearing fluid comprises air.   The fluid contained within the compartment comprises a gas, and the piston assembly further comprises features or components that provide self-alignment using a flow of blow-by gas from the compartment. The assembly described.   The fluid contained within the compartment includes a gas, and the assembly is configured to route the flow of blow-by gas away from a portion of the gap adjacent to the bearing element. The assembly of claim 1, further comprising:   The assembly of claim 1, wherein the fluid contained within the compartment comprises a gas and the piston assembly further comprises a labyrinth seal configured to affect blow-by gas flow.   The assembly of claim 10, wherein the labyrinth seal comprises a plurality of circumferential grooves.   The assembly of claim 1, wherein the bearing fluid flow is configured to form a fluid layer within the gap.   13. The assembly of claim 12, wherein the fluid layer assists in aligning the piston assembly about the bore axis.   The assembly of claim 1, wherein the compartment comprises at least one of a combustion compartment and a gas driven compartment, and wherein the piston surface is configured to contact the compartment.   The assembly of claim 1, wherein the assembly is configured for oilless operation. An assembly configured to translate axially along an axis of a cylinder having a compartment capable of containing fluid, the assembly comprising:
A piston surface configured to contact the compartment;
At least one bearing element configured to provide an outward flow of bearing fluid to a surface of the assembly;
The assembly does not contact the cylinder.   The assembly of claim 16, further comprising a feed passage, wherein the feed passage is configured to receive the bearing fluid from a fluid source and to provide the bearing fluid to the bearing element.   The bearing element comprises a porous annular element, the porous annular element allowing the bearing fluid to flow radially outwardly from the feed passage to the surface of the assembly; The assembly of claim 17.   The bearing element includes one or more radial holes, which allow the bearing fluid to flow radially outward from the feed passage to the surface of the assembly. The assembly of claim 17, wherein the assembly is configured to:   The assembly of claim 16, wherein the fluid contained within the compartment comprises a gas and the piston assembly further comprises a feature that provides self-alignment using a flow of blow-by gas from the compartment. .   The assembly of claim 16, wherein the fluid contained in the compartment comprises a gas, and the assembly further comprises a labyrinth seal configured to affect blow-by gas flow.   The fluid contained within the compartment includes a gas, and the assembly includes one or more passages configured to route the flow of blow-by gas from the fluid compartment away from the surface of the assembly. The assembly of claim 16, further comprising:   The assembly of claim 16, wherein the bearing fluid comprises air.   The assembly of claim 16, wherein the compartment comprises at least one of a combustion compartment and a gas driven compartment, and wherein the piston surface is configured to contact the compartment.   The assembly of claim 16, wherein the assembly is configured for oilless operation. A cylinder of a piston engine,
A bore capable of retracting a piston, wherein the piston is movable along an axis of the bore; and
At least one bearing element configured to provide a flow of bearing fluid to the bore;
The piston is a cylinder that does not contact the cylinder.   27. The cylinder of claim 26, further comprising a feed passage, wherein the feed passage is configured to receive the bearing fluid from a fluid source and provide the bearing fluid to the bearing element.   The bearing element comprises a porous annular element configured to allow the bearing fluid to flow radially inward from the feed passage through the pores to the bore. 28. The cylinder of claim 27, wherein:   The bearing element comprises one or more radial holes, wherein the one or more radial holes allow the bearing fluid to flow radially inward from the feed passage to the bore. The cylinder according to claim 27, which is configured as follows.   27. The cylinder of claim 26, wherein the cylinder is configured for an oilless operation.

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