Anti-clogging starting oil supply system for microturbine engine

Abstract

The application discloses a kind of anti-clogging starting oil supply systems of micro turbo engine, belong to aero-engine technical field.It includes oil supply pipeline, the inlet end of oil supply pipeline is connected with the oil leakage valve, and the outlet end of oil leakage valve is low pressure end.During the starting process of engine, under the action of high pressure of oil supply pipeline, the oil leakage valve is closed;when the starting process is finished, the internal pressure of oil supply pipeline is reduced, the oil leakage valve is automatically opened, and the residual oil in the oil supply pipeline is discharged from the oil leakage valve under the action of pressure difference between the two ends of the oil leakage valve, to prevent the fuel from being heated for a long time in the engine and the oil supply pipeline, and to prevent the starting oil supply channel from being blocked by deposition.

Description

TECHNICAL FIELD

[0001] The present application relates to an engine starting oil supply system, in particular to a micro-turbine engine anti-clogging starting oil supply system, and belongs to the technical field of aero-engines. BACKGROUND

[0002] Fuel delivery pipeline clogging is a common problem of turbine engines, and the formation of fuel delivery pipeline clogging mainly has two ways of fuel deposition and external foreign matter covering. Among them, the fuel deposition is mainly generated by autoxidation under low temperature conditions (below 700℉), and is mainly generated by pyrolysis under high temperature conditions (above 800℉). The external foreign matter is mainly generated by incomplete combustion of fuel. The turbine engine fuel delivery pipeline usually mainly includes two starting fuel delivery pipelines and working fuel delivery pipelines.

[0003] For the working fuel delivery channel, since the internal fuel is in a flowing state, the foreign matter generated by the incomplete combustion of external fuel is difficult to adhere to the working fuel output port, and the internal fuel is in a flowing state, and the temperature rise of the fuel is small, which is difficult to reach the temperature condition required for fuel deposition.

[0004] For the starting fuel delivery channel, since it only has fuel flow during starting, and the incomplete combustion products during working, it is easy to adhere to the surface of the starting nozzle, causing the clogging of the starting nozzle. Although the risk of incomplete combustion products adhering to the surface of the starting nozzle can be reduced by increasing the distance between the starting nozzle and the wall surface of the combustion chamber, with the increase of the distance between the starting nozzle and the combustion chamber, the oil mist sprayed by the starting nozzle is affected by the external airflow and the disturbance of the wall surface of the combustion chamber, which seriously affects the starting effect.

[0005] In addition, for the starting fuel delivery pipeline, after the starting process is completed, since the fuel in the pipeline is in a static state, with the increase of the working time of the engine, the temperature of the fuel in the pipeline gradually increases, which will cause the deposition of the fuel, thereby clogging the starting fuel delivery channel. SUMMARY

[0006] The technical problem to be solved by the present application is to overcome the defects of the prior art and provide a micro-turbine engine anti-clogging starting oil supply system which can effectively avoid the clogging of the starting oil supply pipeline.

[0007] In order to solve the above technical problems, the micro-turbine engine anti-clogging starting oil supply system provided by the present application comprises a fuel supply pipeline, the fuel supply pipeline is connected to the inlet end of a leak valve, and the outlet end of the leak valve is a low-pressure end.

[0008] In the present application, the leak valve comprises a valve shell, a valve core and a sealing gasket.

[0009] The valve shell is a through structure, and a cavity matched with the valve core structure is arranged in the valve shell, wherein a step and a limiting surface are arranged in the cavity, and the limiting surface is arranged below the step.

[0010] The valve core is arranged in the valve shell and can axially move relative to the valve shell.

[0011] The valve core is a T-shaped structure, comprising an oil inlet part and an oil outlet part, wherein the diameter of the oil inlet part is larger than that of the oil outlet part, the oil outlet part is provided with an oil outlet groove in the axial direction, and the oil inlet part is provided with an oil inlet groove in the axial direction.

[0012] The oil outlet part is sequentially sleeved with a sealing gasket and a spring, and the sealing gasket is arranged on the top surface of the oil inlet part.

[0013] The upper end of the spring is in contact with the step.

[0014] When the spring is in a compressed state, the sealing gasket is in close contact with the limiting surface to realize the sealing of the oil leakage valve.

[0015] In the application, the equivalent area of the oil inlet groove is smaller than that of the oil outlet groove.

[0016] In the application, a plurality of automatic telescopic starting nozzles are further connected to the oil supply pipeline.

[0017] In the application, the starting nozzle comprises an inner shell, an outer shell and an atomization unit.

[0018] The atomization unit is arranged in the inner shell and is communicated with the oil supply pipeline.

[0019] The inner shell is arranged in the outer shell, and the inner shell is sequentially sleeved with a sealing gasket and a spring and can axially move relative to the outer shell.

[0020] The limiting surface is arranged in the outer shell.

[0021] One end of the spring is in contact with the outer shell, and the other end is in contact with the sealing gasket.

[0022] When the spring is in a compressed state, the sealing gasket is in close contact with the limiting surface to realize the sealing.

[0023] In the application, a pressure relief hole is arranged below the limiting surface of the outer shell.

[0024] In the application, the low-pressure end is connected to a fuel system, an external atmosphere or a low-pressure area inside an engine.

[0025] In the application, the low-pressure end of the oil leakage valve is connected to a fuel system, and a safety valve is connected between the low-pressure end and the fuel system.

[0026] The present application has the following advantages: (1) During the engine starting process, the oil leakage valve is closed under the action of high pressure in the oil supply pipeline. When the starting process is over, the internal pressure of the oil supply pipeline decreases, the oil leakage valve is automatically opened, and the residual oil in the oil supply pipeline is discharged from the oil leakage valve under the action of pressure difference between the two ends of the oil leakage valve, thereby preventing the fuel from being heated for a long time in the engine and the oil supply pipeline, and preventing the starting oil supply channel from being blocked by deposits. The oil supply channel includes the oil supply pipeline and the starting nozzle; (2) The movable starting nozzle and good sealing ensure the stable and reliable starting of the turbine engine. By moving the starting nozzle away from the wall surface of the combustion chamber during the engine working process and emptying the residual oil in the starting oil supply pipeline, the blockage of the entire starting oil supply system is effectively prevented; (3) The outlet oil groove of the oil leakage valve core has a larger cross-sectional area than the inlet oil groove, which prevents the oil leakage valve from moving unsmoothly or not working effectively due to excessive pressure in the cavity where the oil leakage valve spring is located, thereby ensuring the safety of the system; (4) During the starting process, the starting nozzle is pushed to the wall surface of the combustion chamber by high starting oil supply pressure, and then oil is injected and ignited. After the engine is successfully started, the starting oil supply pump and the starting oil supply valve are closed, the pressure in the starting oil supply pipeline decreases, and the starting nozzle moves away from the wall surface of the combustion chamber under the action of the spring force, thereby preventing incomplete combustion products in the combustion chamber from adhering to the outer surface of the atomizing nozzle, and avoiding the blockage of the starting nozzle; (5) The pressure relief hole provided on the shell of the starting nozzle can prevent the spring from being unable to act due to excessive pressure in the cavity where the spring is located; (6) In the structure for discharging residual oil into the fuel system, a safety valve is added to prevent the fuel system from malfunctioning due to excessive pressure in the fuel system. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0028] Figure 1 Schematic diagram of the starting oil supply system of the micro turbine engine for preventing blockage for discharging residual oil into the atmosphere;

[0029] Figure 2 Schematic diagram of the oil leakage valve structure;

[0030] Figure 3 Schematic diagram of the oil leakage valve core structure;

[0031] Figure 4 Schematic diagram of the oil leakage valve structure integrated with the engine;

[0032] Figure 5 Schematic diagram of the starting nozzle structure;

[0033] Figure 6 Schematic diagram of anti-blocking starting fuel supply system for micro turbine engine with residual oil discharged into fuel system

[0034] Figure 7 Schematic diagram of anti-blocking starting fuel supply system for micro turbine engine with residual oil discharged into low pressure area of engine

[0035] In the figure, 1-external atmosphere, 2-oil leakage outlet pipeline, 3-oil leakage valve, 4-starting fuel supply pipeline, 5-starting fuel supply valve, 6-starting fuel supply pump, 7-fuel system, 8-starting nozzle, 9-safety valve, 10-engine; 31-valve shell, 32-valve core, 33-oil leakage valve spring, 34-oil leakage valve sealing gasket, 35-oil leakage valve shell limiting surface, 36-engine body; 81-inner shell, 82-outer shell, 83-starting nozzle sealing gasket, 84-atomization unit, 85-starting nozzle seat, 86-pressure relief hole, 87-starting nozzle limiting surface, 88-starting nozzle spring. DETAILED DESCRIPTION

[0036] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0038] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0039] In the description of the application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings or the orientation or positional relationship commonly used when the product of the application is used, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0040] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0041] In the description of the application, it should be noted that unless otherwise specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0042] Some embodiments of the application will be described in detail below with reference to the accompanying drawings. The following examples and features in the examples can be combined with each other without conflict.

[0043] As shown in Figure 1 In this embodiment, the anti-blocking starting oil supply system of the micro turbine engine comprises an oil leakage outlet pipeline 2, an oil leakage valve 3, a starting oil supply pipeline 4, a starting oil supply valve 5, a starting oil supply pump 6 and a fuel system 7. The inlet of the starting oil supply pump 6 is connected to the fuel system 7, the outlet of the starting oil supply pump 6 is connected to the starting oil supply valve 5 through the starting oil supply pipeline 4, the starting oil supply valve 5 is connected to the inlets of a plurality of starting nozzles 8 and the inlet of the oil leakage valve 3 through the starting oil supply pipeline 4, and the outlet of the oil leakage valve 3 is connected to the external atmosphere 1 through the oil leakage outlet pipeline 2.

[0044] During the engine starting process, fuel is extracted from the fuel system 7 by the starting fuel pump 6 and pressurized, through the starting fuel valve 5, into the starting fuel pipeline 4, the two ends of which are respectively provided with a plurality of starting nozzle groups composed of starting nozzles 8, and the other end is provided with a drain valve 3. Due to the pressurization of the starting fuel pump 6 and the throttling effect of the starting nozzles 8 and the drain valve 3, the pressure in the starting fuel pipeline 4 rises sharply, thereby overcoming the spring resistance of the drain valve 3 and the starting nozzles 8, causing the drain valve 3 to close and the starting nozzles 8 to move forward, and thus achieving the ignition and starting of the engine. When the starting process is completed, the starting fuel pump 6 and the starting fuel valve 5 are closed, the pressure in the starting fuel pipeline 4 decreases as the fuel is discharged, and under the action of the spring force, the starting nozzles 8 return to their original position, thereby avoiding direct contact between the starting nozzles 8 and the combustion chamber. In addition, the drain valve 3 is opened, and under the action of the relatively high pressure inside the engine, the residual oil in the starting fuel pipeline 4 is discharged outside the engine through the drain valve 3, thereby avoiding the continuous heating of the fuel in the pipeline and the formation of fuel deposits, which can cause blockage.

[0045] As shown in Figure 2 and 3 , the drain valve 3 includes a valve housing 31, a valve core 32, a drain valve spring 33, and a drain valve gasket 34. The valve housing 31 is a through structure, and a cavity is provided inside the valve housing 31 for accommodating the valve core 32, the cavity structure is adapted to the structure of the valve core 32, and the valve core 32 can move axially along the valve housing 31. A step and a drain housing limiting surface 35 are provided in the cavity, and the drain housing limiting surface 35 is located below the step.

[0046] The valve core 32 is of T-shaped structure, adapted to the cavity structure in the valve housing 31, and is divided into an oil inlet portion and an oil outlet portion, the diameter of the oil inlet portion being larger than that of the oil outlet portion, and a step being formed therebetween. The oil outlet portion is provided with four axial oil outlet grooves 342, which are uniformly distributed along the circumference of the oil outlet portion; the bottom of the oil inlet portion is provided with a cross-shaped oil inlet port, and the oil inlet portion is provided with four axial oil inlet grooves 341, which are uniformly distributed along the circumference of the oil inlet portion, and the oil inlet grooves 341 communicate with the oil inlet port.

[0047] The drain valve gasket 34 and the drain valve spring 33 are successively sleeved on the oil outlet portion, and the drain valve gasket 34 is in contact with the top surface of the oil inlet portion. The bottom end of the drain valve spring 33 abuts against the drain valve gasket 34, and the top end abuts against the step of the cavity in the valve housing 31.

[0048] During the engine starting process, under the action of the pressure in the starting oil supply pipeline 4, the valve core 3 and the oil leakage valve sealing gasket 34 overcome the resistance of the oil leakage valve spring 33 and reach the oil leakage housing limiting surface 35, thereby achieving the sealing effect. After the engine 10 is started, with the decrease of the pressure in the starting oil supply pipeline 4, the oil leakage valve sealing gasket 34 is separated from the oil leakage housing limiting surface 35, at this time, the residual oil in the starting oil supply pipeline 4 is discharged outside the engine under the action of the internal pressure during the engine operation.

[0049] In this embodiment, the equivalent area of the oil inlet groove 341 is smaller than the equivalent area of the oil outlet groove 342, thereby preventing the valve core 3 from moving unsmoothly due to the excessively high pressure in the cavity where the oil leakage valve spring 33 is located.

[0050] As shown in the figure, in another embodiment, the oil leakage valve 3 is directly integrated with the engine body 36, and the valve housing 31 is omitted. Figure 4 As shown in the figure, in another embodiment, the oil leakage valve 3 is directly integrated with the engine body 36, and the valve housing 31 is omitted.

[0051] Figure 5 As shown in the figure, in another embodiment, the oil leakage valve 3 is directly integrated with the engine body 36, and the valve housing 31 is omitted.

[0052] The outer shell 82 is internally provided with a cavity for accommodating the inner shell 81, and the cavity is provided with a starting nozzle limiting surface 87.

[0053] The atomization unit 84 is fixed in the inner shell 81, and the front end of the atomization unit 84 is provided with an oil injection hole. The inner shell 81 is arranged in the outer shell 82 and is adapted to the cavity structure inside the outer shell 82. The front part of the inner shell 81 can protrude out of the outer shell 82, that is, the inner shell 81 can move axially relative to the outer shell 82. The tail part of the inner shell 81 forms a step, and the rear end of the inner shell 81 abuts against the starting nozzle seat 85. The starting nozzle sealing gasket 83 and the starting nozzle spring 88 are successively sleeved on the inner shell 81, the starting nozzle sealing gasket 83 is in contact with the step, one end of the starting nozzle spring 88 abuts against the starting nozzle sealing gasket 83, and the other end abuts against the inner side of the outer shell 82. The axial movement of the inner shell 81 relative to the outer shell 82 is realized through the extension and contraction of the starting nozzle spring 88.

[0054] In this embodiment, a pressure relief hole 86 is arranged on the outer shell 82 of the starting nozzle 8, and the pressure relief hole 86 is located below the starting nozzle limiting surface 87. The pressure relief hole 86 can prevent the situation that the starting nozzle spring 88 cannot act due to the excessively high pressure in the cavity where the starting nozzle spring 88 is located. ​

[0055] During engine starting, under the pressure inside the starting fuel supply line 4, the inner housing 81, atomizing unit 84, and starting nozzle sealing gasket 83 overcome the resistance of the starting nozzle spring 88 and reach the outer wall of the combustion chamber. At this time, the starting nozzle sealing gasket 83 is in close contact with the starting nozzle limiting surface 87 inside the outer housing 82, achieving a seal and keeping the pressure in the starting fuel supply line 4 at a high level. This ensures the atomization effect of the starting nozzle 8, enabling fuel injection and ignition, and achieving reliable starting of the engine 10. After the starting process ends, as the starting fuel pump 6 stops working, the pressure in the starting fuel supply line 4 continuously decreases as fuel is continuously discharged. The starting nozzle spring 88 gradually extends back to its original position, pushing the atomizing unit 84 and inner housing 81 away from the combustion chamber wall, thereby protecting the starting nozzle 8.

[0056] In this embodiment, the inner shell 81 of the starting nozzle 8 and the atomizing unit 84 are designed as an integral structure to prevent the core from separating due to internal pressure in the atomizing unit 84, thereby affecting the atomization effect. The connection between the inner shell 81 of the starting nozzle 8 and the atomizing unit 84 is a riveted connection, but threaded connections and elastic retaining rings can also be used.

[0057] like Figure 6 As shown, in another embodiment, the outlet of the oil leakage valve 3 is connected to the safety valve 9 via the oil leakage outlet line 2, and the safety valve 9 is connected to the fuel system 7 via the fuel supply line. This allows residual fuel to be directly discharged into the fuel system 7, and the safety valve 9 is used to prevent excessive pressure in the fuel system 7 from causing malfunctions.

[0058] like Figure 7 As shown, in another embodiment, the outlet of the oil leakage valve 3 is directly connected to the low-pressure chamber of the engine 10 via the oil leakage pipeline 2, so as to discharge residual oil into the low-pressure chamber of the engine 10.

[0059] This invention provides a concept for an anti-clogging starting fuel supply system for a micro-turbine engine. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. Anti-blocking start oil supply system for a microturbine engine, comprising an oil supply circuit, characterized in that: The oil supply pipeline is connected with the inlet end of the oil leakage valve, and the outlet end of the oil leakage valve is a low pressure end; The oil leakage valve comprises a valve shell, a valve core and a sealing gasket; The valve shell is a through structure, and a cavity matched with the structure of the valve core is arranged in the valve shell. The valve core is arranged in the valve shell and can move axially relative to the valve shell. The valve core is a T-shaped structure, comprising an oil inlet part and an oil outlet part. The oil outlet part is provided with an oil outlet groove in the axial direction. The oil inlet part is provided with an oil inlet groove in the axial direction. The oil outlet part is sequentially sleeved with a sealing gasket and a spring, and the sealing gasket is located on the top surface of the oil inlet part.

2. The anti-blocked priming oil supply system for a microturbine engine according to claim 1, characterized in that: The upper end of the spring is in contact with the step.

3. The anti-blocking start-up fuel supply system for a microturbine engine according to claim 1 or 2, characterized in that: When the spring is in a compressed state, the sealing gasket is in close contact with the limiting surface to realize the sealing of the oil leakage valve.

4. The anti-blocked priming oil supply system for a microturbine engine according to claim 3, characterized in that: The equivalent area of the oil inlet groove is smaller than that of the oil outlet groove. A plurality of automatic telescopic starting nozzles are further connected to the oil supply pipeline. The starting nozzle comprises an inner shell, an outer shell and an atomization unit. The atomization unit is arranged in the inner shell and communicates with the oil supply pipeline. The inner shell is arranged in the outer shell and is sequentially sleeved with a sealing gasket and a spring and can move axially relative to the outer shell. The outer shell is provided with a limiting surface.

5. The anti-blocked priming oil supply system for a microturbine engine according to claim 4, characterized in that: One end of the spring is in contact with the outer shell, and the other end is in contact with the sealing gasket.

6. The anti-blocking priming system for a microturbine engine of claim 1 or 2, wherein: When the spring is in a compressed state, the sealing gasket is in close contact with the limiting surface to realize the sealing.

7. The anti-blocking priming system for a microturbine engine of claim 1 or 2, wherein: The limiting surface of the outer shell is provided with a pressure relief hole below. The low pressure end is a fuel system, an external atmosphere or a low pressure area inside an engine. The low pressure end of the oil leakage valve is connected with the fuel system, and a safety valve is connected between the low pressure end and the fuel system.

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