RU2564172C2 - Rotary machine - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine building. The rotary machine includes the work stage. The work stage contains casing with branches and rotor installed in it on the shaft with possibility of rotation. The rotor has spiral multilobe wok channels. The work channels are tightly closed by casing and by the rotating shutters located perpendicular to the rotor. Stage on the shaft are secured by pairs with location in centre of HP or vacuum zone. The shutters are made flexible out of packages of the resilient heat resisting sheets with antifriction wearproof coatings or gaskets.

EFFECT: increased productivity and power, simple design of the machine, and assurance of axial forces compensation.

7 cl, 8 dwg

Description

The invention relates to mechanical engineering and can be used to create an expansion machine for the Rankine cycle, in internal and external combustion engines, as well as in steam and pneumatic drives and compressors.

Known rotary machine, the working stage of which contains a housing with nozzles for supplying and discharging the working fluid and two screw rotors installed in it having multi-starting, tightly engaged profiles with the formation of one working channel [Mikhailov AK, Voroshilov V.P. Compressor machines. M .: Energoatomizdat. 1989, p. 24, Fig. 1.17 and 1.18]. This rotary machine is typically used as a compressor, but it can also be used as a steam expansion machine [RF Patent 2374455].

The disadvantages of rotary machines of this type are:

- Low productivity or power of a single installation due to the participation in the work of only one of the six channels;

- The complexity of the design, including due to the high precision requirements for manufacturing tightly mounted, mutually contacting rotating elements and axial force compensation systems;

- Low reliability due to the large uncompensated axial and radial forces of the rotors;

- Unsuitability for work in ICE and other cycles.

Closest to the proposed invention in terms of technical nature and the achieved result (prototype) is a rotary machine containing a working stage, which includes a rotor having a six-way globoidal profile with working channels tightly covered by a housing and two rotating shutters installed perpendicular to the rotor. The dampers are made of anti-friction wear-resistant plastic with a maximum application temperature of up to 300 ° C. Both dampers are installed mirror symmetrically. Due to this, the radial forces are compensated and the shutters can rotate, since they are mounted on sprockets that are mounted on the shafts. The dampers and sprockets have 11 beams, the rays of the dampers are made straight with a constant width. This rotary machine has one stage and is used as a compressor, and all channels are involved in the operation, and in one stage pressure is increased up to 25 times or more. The body also has nozzles for supplying a working fluid and for removing a compressed working fluid. To compensate for the axial force, the discharge and suction cavities are communicated by a complex system of channels. In addition, the working channels, sprockets and shutters have a complex geometry and require high precision and workmanship [Mikhailov AK, Voroshilov VP Compressor machines. M .: Energoatomizdat. 1989, p. 221, Fig. 7.17].

The disadvantages of rotary machines of this type are:

- Low productivity or power of a single installation;

- The complexity of the design, including due to the high precision requirements for manufacturing tightly mounted, mutually contacting rotating elements and axial force compensation systems;

- Unsuitability for working in Rankine, ICE and other cycles, since it is not intended to use a rotary machine to expand the working fluid, heat recovery is not provided, the shutters do not withstand high temperatures and do not compensate for large temperature expansions.

The present invention solves the problem of increasing the productivity and power of the installation, simplifying the design while providing compensation for axial forces, shaft seals and the possibility of applying it for highly economic work in cycles, including the Rankine cycle and ICE.

To achieve this technical result, in a rotary machine comprising a working stage, which comprises a housing with nozzles and a rotor mounted thereon with a possibility of rotation, having multi-helical working channels tightly closed by the housing and rotating shutters located perpendicular to the rotor, according to the invention, a step on fasten the shaft in pairs with the center of the high pressure or rarefaction zone, and the shutters made flexible from packages of elastic heat-resistant sheets with antifriction onnymi wear-resistant coatings or linings.

Additionally, it is proposed that the shutters be installed with a deepening of the axis of their rotation up to the surface of the rotor forming cylinder.

Moreover, it is proposed to install three or more shutters on the rotor.

In addition, it is proposed to install branch pipes for the intermediate selection of the working fluid in the case of expansion steps.

In addition, it is proposed to connect the compression stage to the expansion stage through the combustion chamber.

In addition, it is proposed to connect the compression stage to the expansion stage by the supply pipes and to install candles and / or fuel nozzles in the housing of the expansion stage behind the supply pipes in high pressure zones.

In addition, it is proposed to include compression and expansion stages with nozzles in the circulation circuit of the working fluid: compression stage, regenerators, hot heat exchanger, expansion stage with working fluid extraction nozzles, regenerator and cold heat exchanger.

The execution of the rotary machine from the steps mounted on the shaft in pairs, with the high pressure or rarefaction zone being placed in the center, allows not only to multiply the productivity (compressor) or power (expansion machine) of a single installation, but also to mutually compensate axial forces from the steps, and also reduce the pressure drops on the seals and, accordingly, the requirements for the design of shaft seals, significantly simplify the design as a whole.

The implementation of the dampers with flexible packages of elastic heat-resistant sheets with heat-insulating and anti-friction wear-resistant coatings or gaskets allows flexible design of the rotor machine to be further simplified by the flexible compensation of manufacturing inaccuracies and its use in ICE, Rankin and other cycles at high working fluid temperatures.

To further increase the volume of working channels and their number, and in this way, the following features allow to increase the productivity or power of the rotor machine:

- Deepening the axis of rotation of the shutters up to the outer surface of the forming cylinder of the rotor - increases the volume of the working channels due to their deepening.

- Installation around the rotor of three or more shutters - increases the volume due to a larger number of working channels.

An additional feature - the installation in the case of the stage of expansion of the nozzles of the intermediate selection of the working fluid - allows you to use the heat partially worked out in the expansion stage of the working fluid (for example, steam) for regenerative heating and / or heat supply and thereby increase the efficiency of the rotary machine.

Connecting the compression stage to the expansion stage through the combustion chamber allows the proposed rotary machine to be used in a power cycle similar to a gas turbine cycle with isobaric heat input.

The connection of the compression stage by the supply pipes to the expansion stage with the installation of a pair of candles and / or fuel nozzles in the housing behind the supply pipes in high pressure zones provides an adjustable volume of the combustion chamber directly in the channels and allows the use of a rotary machine in power cycles similar to ICE cycles.

The inclusion of a compression and expansion stage with nozzles in the circulation circuit of the working fluid: a compression stage, regenerators, a hot heat exchanger, an expansion stage with working fluid take-off nozzles, a regenerator and a cold heat exchanger allows the proposed rotary machine to be used in closed cycles. These are the cycles of the refrigeration machine or the air conditioner, the power cycle of the external combustion engine and the Rankine cycle with steam or organic coolant, moreover, economical with regeneration.

In FIG. 1 schematically shows an embodiment of a rotary expansion machine, FIG. 2 and 3 show a view B and section AA of the working channel with a seal of its proposed design of a flexible shutter, and in FIG. 4 and 5 also show the scheme of the working channels and their overlap by the shutter. Options for incorporating a rotary machine into power cycles are shown in FIG. 6-8: In FIG. 6 - into a cycle of a gas turbine type, in FIG. 7 - in closed cycles and in FIG. 8 - in the Rankine steam cycle.

A rotary expansion machine, for example a driven one operating on compressed air or steam, FIG. 1, includes at least a pair of working steps, right and left, which are mounted mirrored, with the location of the high pressure zone in the middle between them. This provides mutual compensation of axial forces and a twofold increase in plant power, without the need for a seal on the high pressure side. Each stage contains a rotor 2 installed in the housing 1, having multi-start screw working channels 3 formed by screw partitions 4, and the directions of their windings in the steps are opposite. The channels 3 are tightly closed by the housing 1 and the shutters 5 mounted on the sprockets 6 mounted on the shafts 7 mirror symmetrically with respect to the rotor 2.

Before each shutter 5 in the zone of its entrance to the working channel 3 in the housing 1, pipes 8 of the compressed working fluid are installed on both sides of the rotors 2, which serve for its supply, shown by arrow 9. The shading shows the current volume 10 of the channel 3 in the process of expansion of the working fluid. In the housing 1, nozzles 11 of the intermediate selection of the working fluid are also installed, and the arrow 12 shows its exhaust into the nozzles 13. The rotors 2 are mounted on the shaft 14. The shaft is used for power take-off and is removed from the expansion machine 15 through a seal 16 of the simplest type, since the pressure in exhaust is close to atmospheric, the design of the machine is simplified.

In FIG. 2 and 3 show view B and section AA of the working channel 3 with a seal between its screw partitions 4 sprockets 6 of the proposed flexible shutter 5 made of packages of elastic heat-resistant sheets 17, 18, for example, of titanium sheets or heat-resistant steel, and antifriction wear-resistant coatings or gaskets 19. In this case, the first in the direction of travel of the sprocket sheet 17 can be made with the edges bent back in the direction of travel, that is, in the zone of higher temperature and high pressure, which is indicated by P ₊ . Elastic sheets, especially with curved edges, increase the degree of flexible compensation, and the working channel can be performed to a large extent with an arbitrary profile.

The gaskets 19 are located in the movable contact zone between the sheets 17 and the screw partitions 4 of the channel 3. To increase the service life, the packet can be assembled by several pairs of sheets 17 and gaskets 19. In addition, the last sheet 18 can be smaller than the width of the channel 3, and serve better distribution of efforts from the sheets 17 to the sprocket 6.

The proposed designs of the rotor 2 and the working channels 3 are shown in FIG. 4 and 5 as diagrams of their overlapping by flexible shutters 5, rotating on shafts 7. The input of the compressed and exhaust spent working fluid is conventionally shown by arrows 9 and 12. In the prototype, FIG. 4, the rotor 2 is made in the form of a cylinder with helical grooves of rectangular cross section, which are the working channels 3 separated by helical partitions 4.

Additionally, FIG. 5, increase the diameter of the rotor 2, then three or more shutters 5 can be installed around it with a corresponding increase in productivity. The volume of working channels 3 can also be increased, FIG. 5, installing the shutter with a deepening of the axis of their rotation up to the surface of the forming cylinder of the rotor. In this case, the tops of the shutters are buried into the body of the rotor 2, as shown by dashed line 20. The deepening of the axis of rotation of the shaft and shutters into the rotor 2, FIG. 5, even while maintaining a constant cross-sectional area of the channels 3, their volume significantly increases due to deepening and their curvature around the round groove 21. The number of channels blocked by the shutter 5 increases in FIG. 5 from three to five, and the rotor 2 is made like a worm wheel with a round groove 21 (shown by a dotted line), which provides a multiple increase in productivity and power.

The rotary machine, FIG. 1, may be a compressor. The shaft 14 is connected to the engine with a change in the rotation of the shaft 14 and the dampers 5. The nozzles 13 are connected to the atmosphere, and the nozzles 8 of the compressed air are connected to the receiver.

The rotary machine can be used in power cycles. In a gas turbine type cycle, FIG. 6, - with connecting the compression stage to the expansion stage through the combustion chamber. In ICE cycles, with the installation of expansion stages in the housing behind the supply pipes in the high pressure zones, a pair of candles and / or fuel nozzles. In closed loops, FIG. 7, external combustion engines and others - with the circulation circuit of the working fluid.

Here, pairs of working steps are also used, but with the same direction of windings of working channels 3. The steps are mounted on a common shaft with placement in the center of the high pressure zone. This provides mutual compensation of the axial forces of the rotors and the possibility of using simple seals between the steps on the high pressure side due to the small pressure drop between them.

In a rotary gas turbine type cycle machine, FIG. 6, on the right there is a compressor stage 22 with a rotor 2, flexible shutters 5, high-pressure pipes 8 and a suction pipe 23, and on the left - an expansion stage 24 with a high-pressure pipes 8 and an exhaust pipe 25. The rotors of the 2 stages are fixed to the shaft 14 with the location of the zone high pressure between them, and this compensates for axial forces. The shaft 14 is installed in the bearing 26 at its output, since it is mounted on the inlet, the bearing 27 is used, and without a seal, which simplifies the design of the machine. The exhaust pipe 25 of the expansion stage 24 by the exhaust gas duct 28 is connected to the regenerative heat exchanger 29 and then to the atmosphere, and the high-pressure pipe 8 of the compressor 22 by the path 30 is connected in series to the heat exchanger 29, the combustion chamber 31 and to the high-pressure pipe 8 of the expansion stage 24.

Note that the rotary engine for the ICE cycle in the case without exhaust heat recovery is made even simpler by direct connection of the high pressure pipes 8 of the compressor stage 22 to the expansion stage 24 with the installation of a pair of candles and / or fuel nozzles in its body behind the supply pipes in high pressure areas .

A pair of compression stages 22 and expansion 24 mounted on a common shaft 14 can be used in closed cycles such as the power cycle of an external combustion engine and other cycles according to the circuit of FIG. 7. The circulation circuit of the working fluid includes a compression stage (compressor) 22, regenerators 32, 33 of the heat of the exhaust and intermediate taps of the expansion stage 24 with extraction pipes 11 and a hot heat exchanger 34. At the same time, the hot heat exchanger 34 is connected to the circulation circuit on one side by pipelines 35 working fluid, and on the other is connected to a hot spring 36. A cold heat exchanger 37, cooled by a cold coolant stream from the environment, also enters the circulation circuit of the working fluid. Thus, the compression stages 22 and the expansion 24 are included in the circulation of the working fluid: the compression step 22, the regenerators 32 and 33, the hot heat exchanger 34, the expansion stage 24 with the extraction nozzles 11, the regenerator 32 and the cold heat exchanger 37.

Of particular note is the Rankine cycle used in thermal power plants. Here, steam expands hundreds and thousands of times from a pressure of hundreds of atmospheres to a deep vacuum. Such a pressure response can be ensured by the sequential inclusion of only two, three stages of expansion of the proposed design. An expansion machine with two series-connected pairs of high pressure stages 38 and low pressure 39 installed in series and connected by steam lines 40 to the boiler 41 is shown in FIG. 8.

Work

During operation of the rotary expansion machine 15, FIG. 1, a compressed working fluid, such as compressed air or steam, is introduced through the supply pipes 8, as conventionally shown by arrows 9, into the working channels 3 in front of the shutters 5, simultaneously in the right and left steps, and there is no need to use a seal on the high pressure side .

With a further rotation of the shaft 14 and rotors 2, the channels 3 move relative to the housing 1 and are disconnected from the nozzle 8, and the shutters 5, flexibly deformed, enter the channels 3, close their sections tightly and release a portion of steam in these closed volumes. The steam presses on the screw partitions 4 of the channel 3 and the shutter 5, expands in the volume 10 of the working channel 3 highlighted by hatching, performs movement and useful work. In addition, the proportion of partially expanded steam when combining the volume 10 with the hole of the intermediate pipe 11 can be allocated for heating and / or heat recovery, providing an increase in cycle efficiency.

The expansion of the steam ends with the opening of the channel 3 to the exhaust when the beam of the shutter 5 is out of engagement, the channel 3 again starting to fill with steam from the second pipe 8, and the second shutter 5 releases the next portion of steam. The spent working fluid enters the exhaust through the exhaust pipes 13, as shown by arrows 12. Note that the seal 16, which prevents the loss of the spent working fluid through the rotating shaft 14, for example, with the expansion machine 15 operating on compressed air, is operated in very favorable conditions.

The dampers 5 are mounted on sprockets 6 mounted on the shafts 7, and the rays of the sprockets 6, which receive pressure forces, freely pass through the working channels 3 with a gap and rotate in concert with the rotor 2 without direct force contact of these elements - 6 and 2. Sealing of the gaps and temperature extensions is compensated by the elastic expansion of the shutters 5 due to their implementation from packages of elastic heat-resistant sheets 17, 18 with anti-friction wear-resistant coatings or gaskets 19, as shown in FIG. 2 and 3, view B and section AA.

The seal works reliably, since long alternate wear of a package of several pairs of sheets 17 and gaskets 19 can significantly increase the life of the rotary machine. Note that this design is also operable in high-temperature cycles such as gas turbines and internal combustion engines, with sheets 17 with backward-curved edges providing the greatest compensation, FIG. 3, due to their large size and since the pressure P ₊ also acts on the bent edges, pressing the sheets 17 against the screw partitions 4 of the channels 3.

When the rotary machine is operating, its productivity and power are proportional to the speed of rotation of the shaft 14 and the working volume of the channels 3 in the rotor 2. Accordingly, it is important to increase the number and volume of working channels 3. An increase in the volume of working channels can be provided by deepening the shutters 5 into the body of the rotor 2, as shown in FIG. 5. Moreover, the deepening of the axis of rotation of the shutters 5 can be performed up to the surface of the forming cylinder of the rotor 2 with the curvature of the channels 3 around the groove 21 and the deepening of the channels in the body of the rotor 2, as shown by dotted line 20, FIG. 5, as in a worm gear wheel. Note that in this case, the number of channels blocked by each valve 5 increases from three in FIG. 4 to five of FIG. 5. The number of channels and, accordingly, the working volume can be additionally increased by installing three or more shutters 5, naturally, with an increase in the diameter of the rotor 2. As a result, the productivity and power of the rotor machine increase many times.

For the operation of the rotary machine, FIG. 1, as a compressor, the shaft 14 is connected to the engine with the opposite direction of rotation of the shaft 14 and the dampers 5. Air enters through the openings 13 into the open channels 3. Further, as the rotors 2 rotate, the channels 3 are blocked by the dampers 5 and the air is compressed in moving volumes 10 shutters 5 until the channels 3 enter the connection zone of the nozzles 8 of the compressed working fluid and portions of compressed air are not squeezed into the receiver.

The operation of a rotary machine in power cycles, for example, a type of gas turbine, FIG. 6, with the steps connected through the combustion chamber 31, does not differ from that described above. Air is sucked through the pipe 23, is compressed in the compressor stage 22, then is pumped along the path 30 to the expansion stage 24, and moves along the steps 22, 24 in one direction, to the passage. Between the steps, heat is supplied to the working fluid, and in a process close to isobaric. First, the air is heated in the regenerative heat exchanger 29 by the heat of the exhaust and / or intermediate withdrawals from the nozzles 11 by the medium, which is supplied through the gas duct 28 from the exhaust 25 and / or from the exhaust nozzles 11 of the expansion stage, providing increased cycle efficiency. The main heat is introduced into the cycle in the combustion chamber 31 by burning fuel in an air stream, then the combustion products expand in stages 24 with the transmission of the received power through the shaft 14 installed in bearings 26 and 27 to the drive of the compressor 22 and the generator.

Note that a rotary machine with a compressor 22, directly connected by nozzles 8 to the expansion stage 24, when installed in the expansion housing behind the supply nozzles in high pressure zones, a pair of candles and / or fuel nozzles can work in the ICE cycle. Air or a mixture of air and fuel is sucked in, FIG. 6, through the pipe 23, is compressed in the compressor stage 22 and is pumped through the pipes 8 immediately to the expansion stage 24. Here, in the allocated volume 10, after it is disconnected from the pipes 8, fuel is injected through the nozzles or a spark is supplied and rapid combustion of fuel and heat supply with increasing pressure and temperature. Then, the high-temperature combustion products expand, performing the work described above, and rotate the shaft 14. In the carburetor cycle of the internal combustion engine with a mixture of air and fuel, ignition is used, and in the cycle of the diesel engine, fuel nozzles are used, and during the delay of the spark or injection, the volume of the 10 combustion chamber can be adjusted (working channel).

During operation of a pair of compression stages 22 and expansion 24, FIG. 7 mounted on a common shaft 14, in closed cycles such as a gas refrigeration machine, a power cycle of an external combustion engine and other cycles, the principle of operation of the rotary machine does not change. The working fluid enters the compression stage (compressor) 22 through a pipeline 35, it is compressed and supplied to the regenerators 32, 33. In them, the working fluid is heated by the heat of the exhaust and intermediate taps coming from the nozzles 11 of the expansion stage 24, providing an increase in the cycle efficiency . The main heat is supplied in the hot heat exchanger 34 from an external source - the heater 36. Then, the hot working fluid through the pipe 35 enters to the expansion stage 24 to perform useful work. Next, after the exhaust from the expansion machine 24, it is cooled in the regenerative heat exchanger 32, giving off heat, is cooled in the cold heat exchanger 37 with the discharge of heat into the environment by the flow of coolant and again enters the compressor 22. Then the cycle repeats. The operation of steps 22 and 24 is as described above, the axial forces of the steps are mutually compensated.

In the Rankine high pressure steam cycle, a rotary machine is used, FIG. 8, with the sequential inclusion of two or more pairs of steps. Superheated high pressure steam from the boiler 41 through the steam line 40 enters, as shown by arrow 9, into the high pressure unit 38 and here expands to a lower pressure. Next, the steam is returned through the steam lines 40 to the boiler 41, reheated and fed through the steam lines 40 to the low pressure unit 39. In the low pressure unit 39, the steam expands to a deep vacuum and is discharged through the low pressure pipe 13 to a steam condenser. After condensation, the water returns to the boiler 41, evaporates, and the cycle repeats. The operation of the expansion steps is as described above. The axial forces of the steps in the blocks are mutually compensated. In the rotary machine there is only one seal 16 of the shaft 14, and according to the connection diagram, FIG. 8, it is installed in the intermediate pressure zone, and this simplifies its design.

Consider the options for the possible implementation of a rotary machine.

Example 1. A gas turbine-type engine, FIG. 6, to drive an electric generator with a rotation speed of 3000 rpm = 50 Hz. The rotor 2 is made with six channels and two shutters, respectively, for one revolution in the work of 12 channels, and the channels are operated at a frequency of 600 Hz. Thanks to balance of radial and axial forces the smooth course and a low sound level is provided. The degree of pressure increase not less than in the prototype, over 25, the pressure in the combustion chamber 31 more than 2.5 MPa.

Example 2. The expansion machine, FIG. 8, with the sequential inclusion of two blocks of stages with a degree of pressure reduction in each block n = 25, we have P ₁ / P ₂ = n ² = 625. Achievable pressure reduction of 625 times. Steam expansion in low-power steam condensing turbines is typically carried out up to a pressure of P ₂ = 8 kPa = 0.008 MPa, and accordingly, the initial steam pressure will be P ₁ = 5 MPa, typical of low-power turbines. For more powerful steam turbines, expansion is carried out from a pressure of P ₁ = 25.5 MPa to P ₂ = 0.004 MPa with a pressure ratio of P ₁ / P ₂ = 6375. Here, two blocks with a degree of pressure reduction n ₂ = (6375) ^0.5 = 80 or more are actually needed three blocks with a compression ratio n ₃ = (6375) ^0.3333 = 18.54.

Claims (7)

1. A rotary machine, comprising a working stage, which comprises a housing with nozzles and a rotor mounted thereon on the shaft with rotational ability, having multi-screw working channels tightly closed by the housing and rotating shutters perpendicular to the rotor, characterized in that the steps on the shaft are fixed in pairs with placement in the center of a zone of high pressure or rarefaction, and the dampers are made of flexible packages of elastic heat-resistant sheets with anti-friction wear-resistant coatings or gaskets. 2. A rotary machine according to claim 1, characterized in that the shutters are installed with a deepening of the axis of their rotation up to the surface of the rotor forming cylinder. 3. The rotary machine according to claim 1, characterized in that three or more shutters are installed on the rotor. 4. The rotary machine according to claim 1, characterized in that in the case of the expansion stage there are nozzles for intermediate selection of the working fluid. 5. The rotary machine according to claim 1, characterized in that the compression stage is connected to the expansion stage through the combustion chamber. 6. The rotary machine according to claim 1, characterized in that the compression stage is connected by inlet pipes to the expansion stage, and candles and / or fuel nozzles are installed in the housing of the expansion stage behind the inlet pipes in high pressure zones. 7. The rotary machine according to claim 1, characterized in that the compression and expansion stages are included by nozzles in the circulation circuit of the working fluid: the compression step, regenerators, a hot heat exchanger, the expansion step with working fluid extraction nozzles, a regenerator and a cold heat exchanger.

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