JP5184825B2 - Composite diffusion device for reciprocating piston combustion engine and reciprocating piston combustion engine - Google Patents

Abstract

The multi-diffuser (1) has a housing (4) expanding along a longitudinal axis (L) from a diffuser inlet (2) to a diffuser outlet (3), and a diffuser insert (5) arranged within the housing. The diffuser inlet is connected with an output (6) of an exhaust gas turbo-charger (7) and the diffuser outlet is connected with a charge-air cooler (8) of a reciprocating internal combustion engine, such that fresh air (9) is introduced into the cooler from the turbocharger by the diffuser. The diffuser is formed asymmetrical relative to the longitudinal axis.

Description

  The invention relates to a reciprocating piston combustion engine for a reciprocating piston combustion engine, in particular for a two-stroke large diesel engine, and a reciprocating piston combustion engine comprising a composite diffusing device according to the invention as described in the preamble part of the independent claim.

  For example, fresh air is usually designed as an exhaust gas turbocharger after the combustion stroke to achieve improved performance of reciprocating piston combustion engines such as large diesel engines for ships or fixed installations for power generation By a pressure filling group or a forced intake system, it is guided into the combustion chamber of the cylinder at a high pressure. In this regard, some of the thermal energy of the exhaust gas exiting the combustion chamber after the combustion cycle can be utilized. For this purpose, hot exhaust gas is carried from the combustion chamber of the cylinder to the pressure filling group by opening the outlet valve. The pressure filling group basically consists of a turbine driven by hot exhaust gas that receives pressure and enters the pressure filling group. For that part, the turbine provides power to the rotor, which takes in fresh air and compresses it. So-called diffusers, charge air coolers with water separators, and inlet receivers, often referred to simply as turbochargers, were designed as radial compressors in the case of large two-stroke diesel engines, but not in this case The device is connected to the downstream side of a turbine having a rotor as a compressor. From a turbine equipped with a rotor as a compressor, fresh compressed air, also referred to as charge or scavenging, is finally fed into a separate combustion chamber of a large diesel engine cylinder. Therefore, the supply of fresh air can be increased by using this type of pressure filling group, and the efficiency of the combustion process in the combustion chamber of the cylinder can be increased.

  For large diesel engines, the air supply occurs at different locations in the cylinder. Thus, for example, in a longitudinally scavenged two-stroke engine, air is guided into the combustion chamber of the cylinder via a scavenging slot located on the moving surface in the lower region of the cylinder. In a four-stroke engine, the supply air is usually guided into the cylinder's combustion chamber via one or more inlet valves located in the cylinder cover. In this regard, two-stroke engines are also certainly known and have an inlet valve in the cylinder cover instead of a scavenging slot in the lower region of the cylinder.

  In this regard, the diffuser already described above is of great significance for supplying fresh air to the cylinder. As is well known to those skilled in the art, a diffusion device is basically a funnel-shaped dispersion of flow paths. This usually works to delay, i.e. slow the flow rate, whereby the increase in pressure is achieved by Bernoulli's law, which is well known. In order to avoid the separation of the flow in the diffuser from the inner wall of the diffuser and the formation of vortices in the subsonic flow, as would normally occur in the diffuser of a reciprocating piston combustion engine in operating conditions, leading to a reduction in efficiency, The 2θ double aperture angle of the diffuser should not exceed about 16 °, preferably about 8 °. This means that the opening angle formed by the diffuser wall with the longitudinal axis of the diffuser should be less than about 8 °, preferably 4 °, if possible. In this regard, rotary pumps, jet pumps, centrifugal compressors, etc. downstream of the subsonic diffuser need to recover energy by effectively converting kinetic energy into pressure, especially using a centrifugal ventilator It is known to provide

  The above limit of the opening angle has considerable possible drawbacks. Therefore, when trying to reach a predetermined efficiency, it must not be below a certain installation dimension in the direction of the longitudinal axis. This is because, depending on the application and the degree of efficiency obtained, the diffuser can, for example, provide sufficient space in a large two-stroke diesel engine between the turbocharger and the charge air cooler connected by the diffuser. If not, it must have a certain minimum length that is naturally very disadvantageous in the tightened state.

  On the other hand, converting the kinetic energy of the incoming fresh air into pressure energy reduces the degree of efficiency of the diffuser if the specific configuration length of the diffuser must not be exceeded due to geometric boundary conditions. It is possible only to a limited extent.

  In certain cases, this problem can be solved by the use of so-called complex diffusion devices. One skilled in the art understands that a composite diffuser is a concentric nesting of multiple diffusers that form the composite diffuser. That is, two or more hollow bodies in the form of different sized cones having the same or different opening angles are nested concentrically with each other. For example, fresh air is then conveyed from the diffuser inlet to the diffuser outlet into a plurality of concentric conical chambers so that the outer jacket of the composite diffuser is the surface of the cone of the composite diffuser disposed inside each other There may be a significant opening angle greater than 2θ = 16 ° without breaking the upper flow. Thus, despite the fact that the architectural length of the composite diffuser is short compared to a normal diffuser, a sufficient degree of efficiency or an improved degree of efficiency compared to a normal diffuser. Can be further obtained in certain cases.

  One embodiment of this type of composite diffusion device for use in a reciprocating piston combustion engine is discussed in German Patent No. 19710408A1.

  However, it is shown that the known complex diffusion device is actually only a little suitable for use in a reciprocating piston combustion engine, in particular a charge group, i.e. a turbocharger designed as a radial compressor. Has been. This is because flow separation due to the accompanying adverse effects of vortices will occur, thereby reducing the degree of efficiency, thereby known composite diffusion devices in reciprocating piston combustion engines, particularly large two-stroke diesel engines The use of is ultimately not valuable and for this reason they have not been used in the past, for example in the Wartsila heavy-duty diesel engine.

  On the one hand, the structural length of the diffuser in reciprocating piston combustion engines, in particular large two-stroke diesel engines, is basically reduced and / or used conventionally for reasons of cost and structural geometry. There is an urgent need to increase the degree of efficiency compared to existing diffusers.

  The object of the present invention is therefore to have a considerably shorter structural length compared to known diffusers and to a higher degree of efficiency than the diffusers previously used in the prior art in this connection. Or an improved diffuser for a reciprocating piston combustion engine, particularly a large two-stroke diesel engine, preferably having a significantly improved degree of efficiency for the same structural length as a known diffuser It is to propose. Another object of the invention is to propose a reciprocating piston combustion engine, in particular a large two-stroke diesel engine with an improved diffuser.

  The subject-matter of the invention fulfilling these objectives is characterized by the features of the independent claims.

  The dependent claims are related to particularly advantageous embodiments of the invention.

  The present invention is therefore a composite diffuser for a reciprocating piston combustion engine, in particular for a large two-stroke diesel engine, with a diffuser insert arranged inside the diffuser housing, with a longitudinal axis from the diffuser inlet to the diffuser outlet. The present invention relates to a composite diffusion device including a diffusion device housing that branches along. The diffuser inlet can be connected to the outlet of the exhaust gas turbocharger, and the diffuser outlet can be connected to the charge air cooler of the reciprocating piston combustion engine, so that in the operating state of the reciprocating piston combustion engine, it is fresh. Air can be guided from the exhaust gas turbocharger through the combined diffusion device into the charge air cooling device. According to the invention, the composite diffusion device is designed asymmetrically with respect to the longitudinal axis.

  That is, the profile of the velocity distribution of fresh air exiting the turbocharger over the exhaust gas turbocharger outlet diameter and thus naturally over the diffuser inlet diameter never has a fairly symmetrical block-like structure. I found that there was no. This is because the velocity vector of fresh air flowing out of the exhaust gas turbocharger is not constant on the cross-sectional area of the outlet of the exhaust gas turbocharger. -It has a characteristic asymmetry due to the structure of the turbocharger.

  If the exhaust gas turbocharger has been known to those skilled in the art for a long time in its functional configuration and method, for example, as a centrifugal compressor on the charge side, the effluent gas speed and / or direction is determined by the exhaust gas turbocharger. It has been found that at the outlet of the charger compressor, for example, at the inner diameter region at the inner edge of the cross-sectional area of the outlet of the exhaust gas turbocharger, rather than at the outermost edge of the outlet. When viewed over the entire cross-sectional area at the outlet of the exhaust gas turbocharger, a non-rotationally symmetric velocity profile of fresh air entering the diffuser is obtained, i.e. predetermined or at least determined by the configuration of the radial compressor Thereby, an asymmetric velocity profile determined together is obtained.

  This is why a conventional symmetrically constructed composite diffusion device, such as that described in German Patent No. 19710408A1, for example, shows a desired degree of improvement over the efficiency and shortening of the structural length of the composite diffusion device. There is no reason. That is, the symmetry of the velocity profile of the air flowing out of the exhaust gas turbocharger into the symmetric complex diffuser is not comparable to the high symmetry of the known complex diffuser, so the stall of fresh air flowing in This leads to a significant reduction in the specific area of the composite diffuser, and thus the disturbance and the degree of efficiency.

  Such asymmetry in the velocity profile of fresh air entering the diffuser is taken into account by the composite diffuser of the present invention in that the composite diffuser according to the present invention is designed asymmetrically with respect to the longitudinal axis. . In this regard, in the actual case, the configuration of the composite diffuser according to the invention is adapted to the velocity profile that the exhaust gas turbocharger carries at its outlet, and hence the diffuser inlet.

  In this way, it is possible to prevent the flow from breaking at a specific surface area within the composite diffusion device and to prevent the efficiency from being reduced.

  In a preferred embodiment of the composite diffuser according to the invention, the at least one first diffuser insert is designed as a hollow body that branches off in the direction towards the diffuser outlet, in particular in a straight or non-linear conical shape. For example, if only one diffuser insert is provided, this is preferably designed asymmetrically within the diffuser housing with respect to the longitudinal axis of the diffuser housing. This is in particular that the diffuser insert itself is not a circular symmetrical cone and / or that the longitudinal axis of the diffuser insert does not run parallel to and / or not identical to the longitudinal axis of the diffuser housing. Can happen at a point. It can also occur naturally that the diffuser housing itself is not designed symmetrically. The person skilled in the art adapts the structure of the composite diffuser to the incoming fresh air velocity profile, and this and the asymmetry of the composite diffuser according to the invention, even when there are multiple diffuser inserts. Immediately understand how the additional possibilities of creation can be properly used and / or combined.

  In this device, it is possible to provide a diffuser insert that is designed as a small body that branches off in the direction towards the diffuser outlet, in particular in the form of a linear or non-linear small cone and designated as a second diffuser insert. Thus, fresh air cannot flow through the second diffuser insert, but only through its outer surface. In the composite diffuser according to the invention, for example, only a second diffuser insert can be present, and another diffuser insert in the diffuser housing or the second diffuser insert is combined with another diffuser insert. You can see that you can't.

  In this regard, in a particular embodiment, the symmetrical adaptation of the composite diffuser to the incoming fresh air velocity profile is also designed in the form of a sheet metal guide, whereby a small or open cone on the inlet side and outlet side. This can be achieved by the installation of a third diffuser insert.

  All embodiments of diffuser inserts that have been described or that may be obvious within the framework of the invention are by themselves or in combination with the composite diffuser according to the invention alone or in any suitable combination. It will be understood that can be provided at.

  In one embodiment, which is in fact particularly important, the housing section of the diffuser housing and / or the insert section of the diffuser insert is formed as a cross-sectional area that increases in the direction of the diffuser outlet.

  The housing section and / or the insert section can be circular and / or oval and / or regular polygons or irregular polygons, in particular triangular or quadrangular or pentagonal.

  The diffuser housing and / or diffuser insert may extend at a constant opening angle and / or a constant changing opening angle and / or a discontinuously changing opening angle with respect to the longitudinal axis of the composite diffusion device. preferable.

  In this device, the constant opening angle and / or the changing opening angle and / or the discontinuously changing opening angle are a function of the polar angle measured perpendicular to the longitudinal axis.

  In a structural design that is practically important, the at least one diffuser insert and / or diffuser housing is arranged asymmetrically with respect to the longitudinal axis of the diffuser housing, as already described.

  In order to further influence the direction of fresh air flow in the composite diffuser, the diffuser housing and / or diffuser insert may comprise a device with guide elements, in particular helical guide elements, in particular guide vanes. Preferably, the guide element is preferably arranged and designed so as to be able to divide the peripheral flow of fresh air ejected from the exhaust gas turbocharger, in particular to the axial flow.

  In a particularly simple embodiment of the composite diffuser according to the invention, only one diffuser insert is provided.

  The required symmetrical adaptation can also be achieved with such an arrangement in which the composite diffuser extends from the diffuser inlet to the diffuser outlet as a curved composite diffuser along a curved longitudinal axis.

  In this regard, it will be understood that the embodiments described in this application are to be considered as examples and that all suitable combinations not specifically described are included in the present invention.

  Furthermore, the invention relates to a reciprocating piston combustion engine, in particular a large two-stroke diesel engine comprising a composite diffusion device as described above and described below with reference to the drawings.

  The invention is explained in more detail below with the aid of a schematic drawing.

  FIG. 1 shows a large diesel engine formed as a large two-stroke diesel engine with longitudinal scavenging and comprising a composite diffusion device according to the present invention, the interaction of the different components, and indicated below with reference numeral 1 1 is a schematic diagram for explaining the basic configuration of the exhaust gas turbocharger of FIG.

  A large diesel engine typically includes a plurality of cylinders 1000 having outlet valves 1001 disposed within a cylinder cover, in which pistons 1002 are moving surfaces between bottom dead center UT and top dead center OT. It is arranged to move back and forth along. The cylinder 1000 with the cylinder cover and the piston 1002 define the combustion space of the cylinder 1000 in a known manner. A plurality of scavenging openings 1003 are provided in the lower region of the cylinder and are designed as scavenging slots 1003. Depending on the position of the piston 1002, the scavenging slot 1003 is covered or exposed thereby. Fresh air 9, called scavenging 9, can flow through the scavenging slot 1003 into the combustion space of the cylinder 1000. Exhaust gas 1004 generated during combustion flows into the exhaust gas turbocharger 7 through an outlet valve 1001 disposed in the cylinder cover through an exhaust pipe 1005 connected to the exhaust valve 1001.

  In a manner known per se, the exhaust gas turbocharger 7 is fixed to the turbine rotor 721 by means of a compressor 71 having a compressor rotor 711 for compression of air 9 and a shaft as substantial components. And a turbine 72 having a turbine rotor 721 for driving the compressor rotor 711 connected thereto. The turbine 72 and the compressor 71 are arranged in a housing and form an exhaust gas turbocharger, which in this case is formed as a radial compressor on the compressor side. Turbine 72 is driven in a manner known by hot exhaust gas 1004 flowing from the combustion space of cylinder 1000.

  In order to fill the combustion space of the cylinder 1000 with the scavenging air 9, fresh air 9 is sucked by the compressor rotor 711 via the induction stub and compressed in the exhaust gas turbocharger. Fresh air 9 compressed from the exhaust gas turbocharger 7 passes through the downstream composite diffusion device 1 according to the present invention, and also passes through the supply air cooling device 8 through the pressure pipe into the inlet receiver 1006, The fresh air 9 compressed from this receiver finally passes at high pressure through the scavenging slot 1003 into the combustion chamber of the cylinder 1000.

  An exhaust gas turbocharger 7 configured as a radial compressor is shown in somewhat more detail in FIG. Radial compressors are known per se. These are radial compressors with a rotor flow, apart from this, the peripheral components have a radial velocity component for work transport.

  Thus, air is transported at a specific speed V into the diffuser 1 via the outlet 6 of the exhaust gas turbocharger 7 and via the diffuser inlet 2 which is compressed by the impeller in the radial compressor.

  In this regard, given the specific cross-sectional coordinate X on the insert cross-section 500 of the outlet 6 of the exhaust gas turbocharger 7 and thus the cross-sectional coordinate on the housing cross-section 400, the velocity V of the fresh air 9 to be exhausted is It depends on the cross-sectional coordinate X and is therefore not constant on the cross-sectional areas 400, 500. This is because the velocity V of fresh air 9 entering the composite diffuser 1 from the exhaust gas turbocharger 7 at a specific coordinate X follows a velocity profile P that is a function of at least one coordinate X of the cross-sectional areas 400, 500. That's what it means.

  Such asymmetry in the velocity profile P of the fresh air 9 ejected from the exhaust gas turbocharger 7 is due to the asymmetric structure of the composite diffusion device 1 according to the invention, for example as schematically shown in FIG. Be considered. In the embodiment of FIG. 3, fresh air 9 is carried from the exhaust gas turbocharger 7 through the diffuser inlet 2 into the composite diffuser 1 according to the invention. In the composite diffuser 1, the speed of the incoming fresh air 9 is reduced in a manner known per se, whereby an increase in the pressure of the fresh air 9 is achieved by Bernoulli's law, thereby increasing the pressure The charge air cooling device 8 is entered. The composite diffuser 1 according to the invention of FIG. 3 comprises in this respect exactly one diffuser insert 5, 51 in the form of a non-linear cone 51 that branches in the direction towards the diffuser outlet 3. The diffuser housing 4 is designed in exactly the same way as the diffuser insert 51, in this embodiment asymmetric with respect to the longitudinal axis L of the composite diffuser 1, so that the velocity distribution of the incoming fresh air 9 is reduced. The asymmetric shape of the velocity profile P is ideally taken into account, so that a high degree of efficiency can be achieved in the composite diffusion device according to the invention because it does not break the flow of fresh air 9 in the composite diffusion device 1. However, the composite diffusion device 1 of FIG. 3 has a large opening angle and a relatively short structural length.

  A second embodiment of the composite diffuser according to the invention of FIG. 3 with a small diffuser insert 5, 52 is shown in FIG. The apparatus shown in FIG. 4 substantially corresponds to the apparatus of FIG. 3 already described in detail, but in FIG. 4, the diffuser inserts 5, 52 are non-linear cones 51 as described in FIG. Rather than a diverging hollow body 51 in the form of a non-linear small cone 52, which is designed in the form of a non-linear small cone 52, branching in the direction towards the diffuser outlet so that fresh air 9 can be It can only flow around and not through the small cone 52.

  Whether a small diffuser insert 52 or a hollow diffuser insert 51 is used depends in particular on the particular shape of the velocity profile of the velocity distribution of fresh air 9 flowing into the composite diffuser 1 and / or the exhaust. Other area conditions, such as the special design of the gas turbocharger 7 and / or the charge air cooler 8 and / or other requirements such as, for example, the requirements made in the dimensions and shape of the composite diffuser 1 itself It depends on.

  The view of FIG. 5 shows a cross-sectional view of a composite diffuser 1 with two diffuser inserts 5 arranged asymmetrically. The diffusion device housing 4 itself of the composite diffusion device 1 is formed in an elliptical shape that is asymmetric with respect to the longitudinal axis L of the composite diffusion device 1. In addition, the two diffuser inserts 5, 51 formed in the embodiment of FIG. 5 as hollow straight cones 5, 51 branching in the direction towards the diffuser outlet 3, which are not explicitly shown in FIG. 4 are arranged asymmetrically with respect to the longitudinal axis L of the composite diffusion device 1 in the interior 4.

  FIG. 6 shows a cross-section of another embodiment of a composite diffuser 1 with two diffuser inserts 5 formed asymmetrically. In the embodiment of FIG. 6, similar to the embodiment of FIG. 5, the diffuser housing 4 is formed in an elliptical shape, in which two diffuser inserts 5 are formed as hollow elliptical diffuser inserts 51. That is, the asymmetry of the composite diffusion device 1 with respect to the longitudinal axis L is caused by asymmetric molding of the diffusion device housing 4 and the diffusion device inserts 5 and 51.

  In a preferred embodiment, one wall surface of the diffuser insert 5 can be perforated in this device, i.e. provided with holes or openings, so that the flow in the composite diffuser 1 can be fed in fresh. The air 9 geometry and / or velocity profile P can be advantageously influenced in a suitable manner.

A longitudinal section of the composite diffusion device 1 with a constantly varying opening angle α ₂ of the diffusion device housing 4 is shown in FIG. 7, and FIG. 8 shows the embodiment of FIG. 7 in a perspective view.

  The composite diffuser according to FIGS. 7 and 8 has exactly one diffuser insert 5 formed as a hollow cone extending in the direction towards the diffuser outlet 3. For reasons of clarity, only the diffuser housing 4 is shown in this regard in FIG. 8, and the diffuser inserts 5, 51 are not visible.

FIG. 7 shows how the diffusion device is such that the opening angle α ₂ decreases constantly towards the diffusion device inlet 2 and the opening angle α ₁ of the diffusion device inserts 5, 51 is constant along the longitudinal axis L. the opening angle alpha ₂ of the housing 4 clearly show how changes in the constant in the direction of the longitudinal axis L.

In addition, the constantly changing aperture angle α ₂ is a function of the polar angle φ caused by the asymmetry of the composite diffusion device 1 according to FIGS.

  In FIG. 9, the asymmetry in the profile P of the velocity distribution of fresh air 9 flowing into the composite diffuser 1 is likewise taken into account in order to increase the degree of efficiency of the composite diffuser 1 according to the invention. Another embodiment of the present invention is shown with a diffuser insert 5 of the composite diffuser 1 having a curved longitudinal axis L, which is preferred.

  FIGS. 10 and 11 show two embodiments of the composite diffusion device 1 according to the invention with thin metal plate guides 5, 53. The diffusion device inserts 5, 53 of the composite diffusion device 1 according to FIGS. 10 and 11 are not hollow bodies 5, 51 branching in the direction towards the diffusion device outlet 3, but rather the diffusion of the composite diffusion device 1 with respect to the longitudinal axis L. It is an individual sheet metal guide 53 provided asymmetrically in the device housing 4.

  FIG. 12 shows a cross-section of the composite diffusion device 1 according to the invention with a spiral-shaped guide element 10, the spiral-shaped guide element 10 being fresh air exhausted from the exhaust gas turbocharger 7 in the operating state. Nine circumferential flows can be diverted, in particular, arranged and designed to be diverted to axial flow.

  In FIG. 13, a perspective view of another embodiment of the composite diffusion device 1 according to the invention with a guide element 10 is finally shown, the guide element 10 advantageously taking in fresh air 9 that flows in as well. The velocity component of the incoming fresh air directed in the circumferential direction of the composite diffusing device 1 is converted into an axial component, for example as shown schematically in FIG. The fresh air 9 that does basically has only one axial velocity component. In the embodiment of FIG. 13, the guide element 10 is connected to both the outer wall surface of the diffuser insert 5 and the inner wall surface of the diffuser housing 4 in another suitable manner, for example by welding or screwing or fixing. In that respect, the guide element 10 further serves to mount the diffuser insert in the diffuser housing 4 or to stabilize the diffuser insert 5 with the diffuser housing 4.

  Thus, for the first time, a combined diffusion device for reciprocating piston combustion engines, especially large two-stroke diesel engines, has been made available, and even with a very asymmetric velocity profile of the incoming fresh air, the flow does not break internally. As a result, no vortex is formed. Thus, it should be possible to obtain a considerably large opening angle, thus enabling a considerably small construction length and at the same time to withstand disadvantages with a degree of efficiency compared to conventional diffusers or known symmetric composite diffusers There is no composite diffusion device available for the first time. If the configuration length does not play a decisive role, a significant increase in the degree of efficiency can be achieved with the composite diffusion device according to the present invention while maintaining the configuration length of a conventional diffusion device or a composite diffusion device. .

In principle, it is a schematic diagram showing the structure of an exhaust gas turbocharger. 1 is a diagram showing a radial compressor as an exhaust gas turbocharger with a velocity profile of fresh air to be ejected. FIG. 1 shows a first embodiment of a composite diffuser according to the present invention with a hollow conical diffuser insert. FIG. FIG. 4 shows a second embodiment of the composite diffuser according to the invention of FIG. 3 with a small diffuser insert. FIG. 3 is a cross-sectional view of a composite diffuser with two diffuser inserts arranged asymmetrically. FIG. 3 is a cross-sectional view of a composite diffuser with two diffuser inserts designed asymmetrically. FIG. 6 is a longitudinal cross-sectional view of a composite diffusion device with a constantly varying opening angle of the diffusion device housing. FIG. 8 is a perspective view of the diffuser housing of FIG. 7 with an opening angle that varies in the circumferential direction. 1 shows a composite diffusion device according to the invention with a curved longitudinal axis. FIG. It is a figure which shows the 1st Example of the composite-diffusion apparatus provided with the metal thin plate guide. It is a figure which shows the 2nd Example of the composite-diffusion apparatus provided with the metal thin plate guide. FIG. 6 is a cross-sectional view of a composite diffusion device including a spiral-shaped guide element. FIG. 6 is a perspective view of another embodiment with a guide element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite diffuser 3 Diffuser exit 4 Diffuser housing 5 Diffuser insert 6 Exit 7 Exhaust gas / turbocharger 8 Air supply cooler 9 Scavenging 10 Guide element 51 Hollow body 52 Diffuser insert 53 Metal sheet guide 71 Compressor 72 Turbine 400 Housing section 500 Insert section 711 Compressor rotor 721 Turbine rotor 1000 Cylinder 1001 Outlet valve 1002 Piston 1003 Scavenging opening 1004 Exhaust gas 1006 Inlet receiver L Longitudinal axis UT Bottom dead center OT Top dead center P Speed profile V Speed X Cross section Coordinate

Claims (19)

  In the composite diffusion device for a reciprocating piston combustion engine, the composite diffusion device is a diffusion device insert (5, 51, 52, 53) disposed inside the diffusion device housing (4) from the diffusion device inlet (2). Comprising a diffuser housing that branches along the longitudinal axis (L) to the outlet (3), said diffuser inlet (2) being connectable to the outlet (6) of the exhaust gas turbocharger (7); The diffusing device outlet (3) can be connected to an air supply and cooling device (8) of the reciprocating piston combustion engine, whereby fresh air (9) is removed from the exhaust gas and The turbocharger can guide into the charge air cooling device through the composite diffusion device, and the diffusion device housing and the diffusion device insert are nested with each other. The diffusion device housing and the diffusion device insert of the composite diffusion device are both designed asymmetrically with respect to the longitudinal axis (L), and the diffusion device housing and the diffusion device housing The asymmetric design of the diffuser insert is adapted to the fresh air velocity profile at the diffuser inlet so as to prevent the fresh air flow from breaking at surfaces within the diffuser. A compound diffusion device characterized by that.   The composite diffuser according to claim 1, wherein at least the first diffuser insert (51) is designed as a hollow body (51) that branches in a direction towards the diffuser outlet (3).   3. The composite diffusion device according to claim 2, wherein the hollow body (51) is designed in the form of a straight or non-linear cone (51).   3. The composite diffuser according to claim 1, wherein the second diffuser insert (52) is designed as a small body (52) that branches in a direction towards the diffuser outlet (3).   5. The composite diffusion device according to claim 4, wherein the small body (52) is designed in the form of a straight or non-linear cone (52).   6. The composite diffuser according to any one of claims 1 to 5, wherein the third diffuser insert (53) is designed in the form of a sheet metal guide (53).   The housing section (400) of the diffuser housing (4) and / or the insert section (500) of the diffuser housing (4) and / or the insert section (500) of the diffuser insert (5) 7. The composite diffusion device according to claim 1, wherein the composite diffusion device is formed as a cross-sectional area (400, 500) that increases in the direction of the diffusion device outlet (3).   8. The housing according to claim 1, wherein the housing section (400) and / or the insert section (500) is circular and / or elliptical and / or regular polygonal or irregular polygonal. A composite diffusion device according to claim 1. The opening angle (alpha _2), and / or the opening angle of the diffuser insert (5) of the diffuser housing (4) (alpha ₁₎ is a constant aperture angle degrees relative to the longitudinal axis (L), and the aperture angle of which varies / or constant, and / or the opening angle that varies non-constant, complex spreading apparatus according to any one of claims 1 to 8. The composite diffusion device according to claim 9 , wherein the opening angle (α ₁ ) is constant and the opening angle (α ₂ ) increases along the longitudinal axis (L). Before KiHiraki opening angle (alpha _1), and / or the opening angle (alpha ₂₎ is a function of the polar angle measured perpendicular to the longitudinal axis (L) (φ), according to claim 9 or 10 Complex diffuser.   12. At least one diffuser insert (5) and / or the diffuser housing (4) are arranged asymmetrically with respect to the longitudinal axis (L) of the diffuser housing (4). The composite diffusion apparatus as described in any one of the above.   The diffuser housing (4) and / or the diffuser insert (5) comprises a guide element (10), which guide element (10) is the fresh air (from the exhaust gas turbocharger). The composite diffusion device according to any one of claims 1 to 12, wherein the peripheral flow of 9) can be changed.   14. The composite diffusion device according to claim 13, wherein the guide element (10) is a spiral guide element (10).   15. A composite diffusion device according to claim 13 or 14, wherein the guide element (10) is a device comprising guide vanes (10).   16. The composite diffusion device according to any one of claims 13 to 15, wherein the peripheral flow of the fresh air (9) can be converted into an axial flow.   17. A composite diffuser according to any one of the preceding claims, wherein exactly one diffuser insert (5) is provided.   18. A compound diffusion device curved along a curved longitudinal axis (L), extending from the composite device inlet (2) to the composite device outlet (3). Complex diffuser. A reciprocating piston combustion engine comprising a composite diffusion device (1) according to any one of the preceding claims.

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