Constant differential pressure lubricating oil supply system simulation test system and test method

Abstract

This invention provides a simulation test system for a constant differential pressure lubricating oil supply system. The test system includes a supply unit for providing a stable pressure oil source, a simulation unit connected to the supply unit for simulating the lubricating oil chamber of an aero-engine, a throttling constant differential pressure regulating valve for adjusting the oil pressure input to the simulation unit, and a test unit for measuring the flow rate and pressure within the simulation unit. The simulation unit includes a throttling ventilation lubricating oil chamber and a free ventilation lubricating oil chamber, and the throttling constant differential pressure regulating valve is located between the supply unit and the throttling ventilation lubricating oil chamber. The constant differential pressure lubricating oil supply system simulation test system provided by this invention can simulate the oil supply regulation characteristics of an aero-engine constant differential pressure lubricating oil supply system under steady-state and rapid pressure changes in the bearing chamber. It enables the verification of the function and performance of the constant differential pressure lubricating oil supply system on a test apparatus, reducing the verification risk and cost of the supply system.

Description

Technical Field

[0001] This invention belongs to the technical field of aero-engine lubricating oil systems, specifically relating to a constant pressure differential lubricating oil supply system simulation test system and test method. Background Technology

[0002] The lubricating oil supply system of an aircraft engine provides a continuous and appropriate amount of lubricating oil to engine bearings, gears, sealing components, etc. On the one hand, it reduces friction and wear on moving mating surfaces and plays a lubricating role; on the other hand, it removes heat generated by rotating moving components containing friction pairs and heat transferred from the environment, playing a certain cooling role and ensuring the working reliability and service life of related components.

[0003] Due to limitations imposed by existing main shaft contact sealing technology, some aero engines employ non-contact grate seals for their lubricating oil chambers containing intermediate seals. To reduce gas leakage from these grate seals, throttling and pressurization of the lubricating oil chamber ventilation is necessary, resulting in significant pressure variations within the chamber. To ensure a stable lubricating oil supply to the pressurized lubricating oil chamber, a constant differential pressure oil supply system is required. This system involves pressurizing the lubricating oil with an oil pump and then supplying it to the pressurized lubricating oil chamber via a constant differential pressure regulating valve. This supply method effectively guarantees the lubricating oil supply to each lubrication point, solving the problem of stable lubricating oil supply to the bearing chamber under wide pressure range operating conditions.

[0004] However, the adjustment principle of the constant differential pressure lubricating oil supply system is relatively complex. The oil supply scheme of using constant differential pressure lubrication for a specific lubricating oil chamber of an aero-engine and setting a constant differential pressure regulating valve in its supply line is the first of its kind in domestic aero-engine power lubrication systems, and there are deficiencies in system verification. The impact of pressure changes in the lubricating oil chamber using constant differential pressure lubrication on the supply flow rate, total supply flow rate, and pressure of other lubricating oil chambers is not well understood, and the response of the constant differential pressure regulating valve to changes in the pressure of the pressurized lubricating oil chamber is still unclear. There is no dedicated system test bench and test method for the constant differential pressure lubricating oil supply system, and the verification of the oil supply system can only be carried out with the whole machine, which increases the risk of the lubricating oil system, the number of design iterations, and the test cost. The lubricating oil pump (integrated constant pressure valve) and the constant differential pressure regulating valve in the oil supply system only have separate test benches, which cannot complete the joint debugging of the pump and the constant differential pressure regulating valve, resulting in a certain deviation between the working performance in the installed state and the individual lubricating oil pump and constant differential pressure regulating valve tests. Summary of the Invention

[0005] To address the aforementioned issues, the present invention aims to provide a simulation test system and method for a constant differential pressure lubricating oil supply system. This test system and method enable the functional and performance verification of the constant differential pressure lubricating oil supply system for aero-engines, allowing for the understanding of the working characteristics of the constant differential pressure lubricating oil supply system and the influence relationship between relevant parameters. This overcomes the high risk and high cost issues associated with lubricating oil systems only being verified along with the entire aircraft.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a constant differential pressure lubricating oil supply system simulation test system. The test system includes an oil supply unit for providing a stable pressure oil source, a simulation unit connected to the oil supply unit for simulating the lubricating oil chamber of an aircraft engine, a throttling constant differential pressure regulating valve for adjusting the oil pressure input to the simulation unit, and a test unit for measuring the flow rate and pressure within the simulation unit. The simulation unit includes a throttling ventilation lubricating oil chamber and a free ventilation lubricating oil chamber, and the throttling constant differential pressure regulating valve is disposed between the oil supply unit and the throttling ventilation lubricating oil chamber.

[0007] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following features: the oil supply unit includes a lubricating oil tank for storing lubricating oil, a lubricating oil filter installed at the lubricating oil outlet of the lubricating oil tank, and a supply and return oil pump assembly.

[0008] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following feature: the oil supply and return pump assembly includes a primary oil supply stage and a multi-stage oil return stage rotor gear pump, wherein the primary oil supply stage is equipped with a constant pressure regulating valve.

[0009] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following features: the outside of the throttling and ventilation lubricating oil chamber is provided with a transparent observation window and the top is provided with a venting valve; the throttling and ventilation lubricating oil chamber is connected to a pressure boosting control valve and a high-pressure gas cylinder for adjusting the pressure inside the throttling and ventilation lubricating oil chamber.

[0010] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following features: the free ventilation lubricating oil chamber is connected to the oil outlet end of the oil supply unit through a first valve, a third valve and a free ventilation lubricating oil chamber equivalent nozzle arranged in sequence; the free ventilation lubricating oil chamber is connected to the lubricating oil tank through the oil supply and return assembly to form a return oil circuit.

[0011] The constant differential pressure lubricating oil supply system simulation test system provided by the present invention also has the following features: the throttling constant differential pressure regulating valve includes a hollow valve housing. The surface of the valve housing is provided with an oil supply inlet for oil inlet, an oil supply outlet for oil outlet, a cavity pressure sensing inlet for sensing the cavity pressure of the throttling ventilation lubricating oil chamber, and an oil pressure sensing outlet for sensing the oil supply outlet pressure. The hollow cavity of the valve housing is provided with a slide valve for adjusting the outlet flow rate, a spring for providing the pushing force to push the slide valve, and a guide rod and adjusting screw for adjusting the spring compression. The slide valve is provided with a throttling orifice that cooperates with the oil supply outlet to adjust the oil supply flow rate.

[0012] The constant differential pressure lubricating oil supply system simulation test system provided by the present invention also has the following features: the test unit includes a fourth pressure sensor for measuring the pressure of the lubricating oil tank in the supply unit, a temperature sensor for measuring the temperature inside the lubricating oil tank in the supply unit, a first pressure sensor for measuring the total oil supply pressure of the supply unit, a first flow meter for measuring the total oil supply flow of the supply unit, a fifth pressure sensor for measuring the oil supply pressure of the free ventilation lubricating oil chamber, a second flow meter for measuring the oil supply flow of the free ventilation lubricating oil chamber, a second pressure sensor for measuring the lubricating oil pressure at the inlet of the throttling constant differential pressure regulating valve, a sixth pressure sensor for measuring the oil supply pressure of the throttling ventilation lubricating oil chamber, a third flow meter for measuring the oil supply flow of the throttling ventilation lubricating oil chamber, and a third pressure sensor for measuring the cavity pressure of the throttling ventilation lubricating oil chamber.

[0013] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following features: the test system further includes a lubricating oil tank vent valve installed on the lubricating oil tank of the supply unit for adjusting the pressure of the lubricating oil tank, a pressure boosting simulation chamber vent valve for depressurizing the throttling ventilation lubricating oil chamber, and a second valve installed on the return oil pipeline of the throttling ventilation lubricating oil chamber.

[0014] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following feature: the free ventilation lubricating oil chamber is further provided with a free ventilation lubricating oil chamber vent.

[0015] The constant pressure differential lubricating oil supply system simulation test system provided by the present invention also has the following feature: the lubricating oil tank is equipped with a heating resistor for heating the lubricating oil.

[0016] Another object of the present invention is to provide a simulation test method for a constant differential pressure lubricating oil supply system, wherein the test method uses the test system described in any of the foregoing claims and includes the following steps:

[0017] S1: Completely close the boost control valve, heat the lubricating oil in the oil tank to 80-90℃, adjust the speed of the oil supply and return pump assembly to the speed at the design point of the simulated engine, then adjust the first valve to ensure that the pressure value of the first pressure sensor is stable to the total oil supply pressure of the simulated engine lubricating oil system at the design point, and adjust the depth of the lever on the constant pressure valve so that the flow value of the first flow meter reaches the range of the design lubricating oil circulation volume of the simulated engine;

[0018] S2: Maintain the oil supply and return pump assembly speed at the simulated engine design point speed, adjust the first valve and the third valve so that the pressure values ​​of the first pressure sensor and the second pressure sensor are respectively the total oil supply pressure of the simulated engine lubricating oil system at the design point and the inlet pressure of the throttling constant differential pressure regulating valve. At the same time, ensure that the flow rate of the first flow meter is within the design lubricating oil circulation range of the simulated engine. Then adjust the adjusting screw so that the difference between the pressure value of the sixth pressure sensor and the pressure value of the third pressure sensor is the set working differential pressure of the throttling constant differential pressure regulating valve. At the same time, the flow rate of the third flow meter meets the design oil supply flow rate of the simulated engine throttling ventilation lubricating oil chamber nozzle.

[0019] S3: Maintain the oil supply and return pump assembly speed at the simulated engine design point speed, adjust the opening of the second valve so that the lubricating oil in the throttling ventilation lubricating oil chamber overflows the return oil pipe opening to create a liquid level, completely close the throttling ventilation lubricating oil chamber vent valve, adjust the boost control valve so that the pressure value of the third pressure sensor increases to 400 kPa in a 50 kPa gradient, and collect the system's pressure, flow rate values ​​and fluctuations at each steady-state pressure point, completely close the boost control valve, increase the opening of the throttling ventilation lubricating oil chamber vent valve so that the pressure value of the third pressure sensor decreases to atmospheric pressure in a 50 kPa gradient, and repeat the collection and analysis of the corresponding steady-state point data;

[0020] S4: Adjust the booster control valve and the vent valve of the throttling ventilation lubricating oil chamber, adjust the pressure value of the third pressure sensor to vary between 100-410KPa, determine whether the system's oil supply flow and pressure meet the requirements, whether the fluctuation increases, and repeat S4 to verify whether the valve is stuck.

[0021] S5: Completely close the control valve, fully open the vent valve of the throttling ventilation lubricating oil chamber, adjust the speed of the oil supply and return pump assembly, and collect the flow rate and pressure of the lubricating oil supply system at different speeds.

[0022] Beneficial effects

[0023] The constant differential pressure lubricating oil supply system simulation test system provided by this invention can simulate the oil supply regulation characteristics of the constant differential pressure lubricating oil supply system of aero-engine under steady-state and rapid pressure changes in the bearing cavity. It realizes the verification of the function and performance of the constant differential pressure lubricating oil supply system on the test instrument, reducing the verification risk and cost of the oil supply system.

[0024] The constant differential pressure lubricating oil supply system simulation test method provided by this invention can be used to determine the final installation and delivery technical status of the oil supply and return pump assembly and the constant differential pressure regulating valve. The working boundary is close to that of a real engine, which ensures the reliability of the test. At the same time, the system pressure and flow rate measured in this test can be used to verify and check the design method and model. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of the constant differential pressure lubricating oil supply system simulation test system provided in the embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the throttling constant differential pressure regulating valve structure provided in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the constant pressure regulating valve integrated on the lubricating oil pump in an embodiment of the present invention.

[0029] Among them, 1-oil tank; 2-oil filter; 3-motor; 4-gearbox; 5-oil supply and return pump assembly; 6-first pressure sensor; 7-first valve; 8-first flow meter; 9-second pressure sensor; 10-throttling constant pressure differential regulating valve; 11-third pressure sensor; 12-vent valve; 13-throttling ventilated oil chamber; 14-pressurization control valve; 15-high pressure gas cylinder; 16-transparent observation window; 17-second valve; 18-fourth pressure sensor; 19-oil tank vent valve; 20-heating resistor; 21-temperature sensor; 22-free ventilation oil chamber vent; 23-self-ventilated oil chamber vent; 24-Free ventilation lubricating oil chamber; 25-Fifth pressure sensor; 26-Second flow meter; 27-Third valve; 28-Sixth pressure sensor; 29-Third flow meter; 30-Throttle ventilation lubricating oil chamber equivalent nozzle; 31-Oil supply inlet; 32-Valve housing; 33-Slide valve; 34-Cavity pressure sensing inlet; 35-Spring; 36-Guide rod; 37-Adjusting screw; 38-Oil pressure sensing outlet; 39-Oil supply outlet; 40-Throttle orifice; 41-Lever; 42-Spring seat; 43-Constant pressure valve spring; 44-Valve; 45-Overflow inlet; 46-Overflow outlet. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent changes or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the protection scope of the present invention.

[0031] In the description of the embodiments of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the invention.

[0032] Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0033] The terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of these terms in this invention based on the specific circumstances.

[0034] like Figures 1-3 As shown, this embodiment of the invention provides a simulation test system for a constant differential pressure lubricating oil supply system. The test system includes an oil supply unit for providing a stable pressure oil source, a simulation unit connected to the oil supply unit for simulating the lubricating oil chamber of an aero-engine, a throttling constant differential pressure regulating valve 10 for adjusting the oil pressure input to the simulation unit, and a test unit for measuring the flow rate and pressure within the simulation unit. The simulation unit includes a throttling ventilation lubricating oil chamber 13 and a free ventilation lubricating oil chamber 23. The throttling constant differential pressure regulating valve 10 is disposed between the oil supply unit and the throttling ventilation lubricating oil chamber 13. The throttling ventilation lubricating oil chamber 13 refers to the lubricating oil chamber in an aero-engine that requires ventilation and throttling to increase the chamber pressure, while the free ventilation lubricating oil chamber 23 refers to the lubricating oil chamber in an aero-engine that does not require ventilation and throttling.

[0035] In some embodiments, the oil supply unit includes an oil tank 1 for storing lubricating oil, an oil filter 2 disposed at the lubricating oil outlet of the oil tank, and an oil supply and return pump assembly 5.

[0036] In some embodiments, the oil supply and return pump assembly 5 is a rotary gear pump, comprising a single-stage oil supply stage and multiple-stage oil return stages. The oil supply stage is designed to supply oil at a rate of 126 L / min, and the maximum designed return rate of the oil return stages is 139 L / min. The oil supply stage of the oil supply and return pump assembly 5 integrates a constant pressure regulating valve. The rotational speed of the oil supply and return pump assembly 5 is controlled by the electric motor 3 and the gearbox 4.

[0037] In some embodiments, the constant pressure regulating valve includes a lever 41, a spring seat 42, a constant pressure valve spring 43, a valve 44, an overflow inlet 45, and an overflow outlet 46, as shown in the figure. Figure 3 As shown, the constant pressure regulating valve is connected to the oil supply stage outlet of the oil supply and return pump assembly via the overflow inlet 45 and to the oil supply stage inlet of the oil supply and return pump assembly via the overflow outlet 46. When the lubricating oil pressure at the oil supply stage outlet is greater than the set pressure of the constant pressure valve, the lubricating oil pushes open the valve 44 and returns to the oil supply stage inlet from the overflow outlet 46, ensuring a constant oil supply stage outlet pressure. The working pressure of the constant pressure valve is set by adjusting the compression of the constant pressure valve spring 43 by adjusting the lever 41. In this example, the design value of the working pressure of the constant pressure valve can be set to any value within the range of 400 to 900 kPa.

[0038] In some embodiments, the throttling ventilation lubricating oil chamber 13 is provided with a transparent observation window 16 on the outside and a venting valve 12 on the top. The throttling ventilation lubricating oil chamber 13 is connected to a pressure boosting control valve 14 and a high-pressure gas cylinder 15 for adjusting the pressure inside the throttling ventilation lubricating oil chamber. The throttling ventilation lubricating oil chamber 16 is connected to the pressure boosting control valve 14 and the high-pressure gas cylinder 15 in sequence through a pressure boosting pipeline. It is also connected to the throttling ventilation lubricating oil pressure boosting simulation chamber 13 and the pressure sensing inlet 34 of the throttling constant pressure differential regulating valve chamber through a ventilation pipeline, and a third pressure sensor 11 is installed in the ventilation pipeline.

[0039] In some embodiments, the free-ventilated lubricating oil chamber 23 is connected to the oil outlet of the oil supply unit through a first valve 7, a third valve 27 and a free-ventilated lubricating oil chamber equivalent nozzle 24 arranged in sequence. The free-ventilated lubricating oil chamber 23 is connected to the lubricating oil tank 1 through the oil supply and return pump assembly 5 to form a return oil path.

[0040] In the above embodiments, the inner diameter of the equivalent nozzle 24 of the free-ventilation lubricating chamber is determined according to the calibrated pressure difference and flow rate of the nozzle in the engine's free-ventilation lubricating chamber; the inner diameter of the equivalent nozzle 30 of the throttling lubricating chamber is determined according to the calibrated pressure difference and flow rate of the nozzle in the engine's throttling lubricating chamber. The first valve 7 and the third valve 27 are used to simulate the flow resistance of the fuel oil radiator, oil filter 2, oil supply throttling element, and pipeline in the engine's fuel supply system, which can realize the control of the total system fuel supply pressure, the fuel supply pressure of the throttling lubricating chamber 13, and the free-ventilation lubricating chamber 23. The second valve 17 is used to control the return oil flow area of ​​the throttling lubricating pressurization simulation chamber, thereby controlling its lubricating oil level.

[0041] In some embodiments, such as Figure 2 As shown, the throttling constant differential pressure regulating valve 10 includes a hollow valve housing 32. The surface of the valve housing 32 is provided with an oil supply inlet 31 for oil inlet, an oil supply outlet 39 for oil outlet, a cavity pressure sensing inlet 34 for sensing the cavity pressure of the throttling ventilation lubricating oil cavity, and an oil pressure sensing outlet 38 for sensing the oil supply outlet pressure. The hollow cavity of the valve housing 32 is provided with a slide valve 33 for adjusting the outlet flow rate, a spring 35 for providing the pushing force to push the slide valve 33, and a guide rod 36 and an adjusting screw 37 for adjusting the compression of the spring 35. The slide valve 33 is provided with a throttling orifice 40 that cooperates with the valve housing to adjust the oil supply flow rate.

[0042] In the above embodiment, the throttling constant differential pressure regulating valve 10 can adjust the position of the guide rod 36 and the compression of the spring 35 by adjusting the screw 37 to set the working differential pressure of the constant differential pressure regulating valve. When the pressure difference between the lubricating oil pressure at the oil supply inlet 31 and the pressure difference between the cavity pressure sensing inlet 34 is less than the valve's set working differential pressure, the slide valve 33 moves to the leftmost end under the action of the spring preload. At this time, the opening of the throttling orifice 40 formed by the slide valve 33 and the housing is at its maximum, and there is no throttling or pressure reduction effect on the lubricating oil at the oil supply inlet 31. When the pressure difference between the lubricating oil pressure at the oil supply inlet 31 and the pressure difference between the cavity pressure sensing inlet 34 is greater than the valve's set working differential pressure, the slide valve 33 moves to the right, the opening of the throttling orifice 40 decreases, the valve is in a throttling state, the lubricating oil pressure at the oil supply inlet 32 ​​is reduced to the pressure at the oil supply outlet 39, and the pressure difference between the oil supply outlet 39 and the pressure difference between the cavity pressure sensing inlet 34 is equal to the valve's set working differential pressure, thus realizing the regulation of constant differential pressure oil supply.

[0043] In some embodiments, the test unit includes a fourth pressure sensor 18 for measuring the pressure of the lubricating oil tank 1 in the oil supply unit, a temperature sensor 21 for measuring the temperature inside the lubricating oil tank in the oil supply unit, a first pressure sensor 6 for measuring the total oil supply pressure of the oil supply unit, a first flow meter 8 for measuring the total oil supply flow of the oil supply unit, a fifth pressure sensor 25 for measuring the oil supply pressure of the free ventilation lubricating oil chamber, a second flow meter 26 for measuring the oil supply flow of the free ventilation lubricating oil chamber, a second pressure sensor 9 for measuring the lubricating oil pressure at the inlet of the throttling constant differential pressure regulating valve, a sixth pressure sensor 28 for measuring the oil supply pressure of the throttling ventilation lubricating oil chamber, a third flow meter 29 for measuring the oil supply flow of the throttling ventilation lubricating oil chamber, and a third pressure sensor 11 for measuring the cavity pressure of the throttling ventilation lubricating oil chamber.

[0044] In some embodiments, the test system further includes a lubricating oil tank vent valve 19 installed on the lubricating oil tank of the oil supply unit for adjusting the pressure of the lubricating oil tank, a pressure boosting simulation chamber vent valve for depressurizing the throttling and ventilation lubricating oil chamber, and a second valve 17 installed on the return oil pipeline of the throttling and ventilation lubricating oil chamber.

[0045] In some embodiments, the free-ventilation lubricating oil cavity is further provided with a free-ventilation lubricating oil vent 22.

[0046] In some embodiments, the lubricating oil tank is equipped with a heating resistor 20 for heating the lubricating oil.

[0047] In some embodiments, the oil supply line of the system's lubricating oil tank 1 is sequentially connected to the lubricating oil filter 2, the oil supply and return pump assembly 5 supply stage, the first pressure sensor 6, the first valve 7, and the first flow meter 8 along the flow direction; after the first flow meter 8, the oil supply line is divided into two branches via a tee. The first branch is sequentially connected to the throttling constant pressure differential regulating valve 10, the throttling ventilation lubricating oil pressurization simulation chamber 13, and the second valve 17 along the flow direction to form a closed loop; the second branch is sequentially connected to the third valve 27, the second flow meter 26, the fifth pressure sensor 25, and the non-pressurization chamber free ventilation lubricating oil equivalent. Nozzle 24, free ventilation lubricating oil chamber non-pressurization simulation chamber 23, and oil return pump assembly 5 form a closed return oil stage; the first branch is connected to the oil supply inlet 31 of the throttling constant differential pressure regulating valve through the valve inlet pipe, the second pressure sensor 9 is installed in the valve inlet pipe, and the oil supply outlet 39 of the throttling constant differential pressure regulating valve is connected to the throttling ventilation lubricating oil pressurization simulation chamber 13 through the valve outlet pipe, the sixth pressure sensor 28, the third flow meter 29 and the equivalent nozzle 30 of the throttling ventilation lubricating oil pressurization chamber are installed in sequence along the flow direction of the valve outlet pipe.

[0048] In some embodiments, a simulation test method for a constant differential pressure lubricating oil supply system is provided. The test method uses the test system described in any of the foregoing embodiments and includes the following steps:

[0049] S1: Completely close the boost control valve, heat the lubricating oil temperature in the lubricating oil tank to 80-90℃, adjust the speed of the oil supply and return pump assembly to the speed at the simulated engine design point, then adjust the first valve 7 to ensure that the pressure value of the first pressure sensor 6 is stable to the total oil supply pressure at the simulated engine lubricating oil system design point, and adjust the screw depth of the lever 41 on the constant pressure valve so that the flow value of the first flow meter 8 reaches the range of the simulated engine's designed lubricating oil circulation volume;

[0050] S2: Maintain the rotation speed of the oil supply and return pump assembly 5 at the simulated engine design point speed, adjust the first valve 7 and the third valve 27 so that the pressure values ​​of the first pressure sensor 6 and the second pressure sensor 9 are respectively the total oil supply pressure and the inlet pressure of the throttling constant differential pressure regulating valve 10 at the simulated engine lubricating oil system design point, while ensuring that the flow rate of the first flow meter 8 is within the design lubricating oil circulation range of the simulated engine. Then adjust the adjusting screw 37 so that the difference between the pressure value of the sixth pressure sensor 6 and the pressure value of the third pressure sensor 11 is the set working differential pressure of the throttling constant differential pressure regulating valve 10, while the flow rate of the third flow meter 29 meets the design oil supply flow rate of the simulated engine throttling ventilation lubricating oil chamber nozzle.

[0051] S3: Maintain the oil supply and return pump assembly speed at the simulated engine design point speed, adjust the opening of the second valve 17 so that the lubricating oil in the throttling ventilation lubricating oil chamber 13 does not exceed the return oil pipe opening to generate a liquid surface, completely close the throttling ventilation lubricating oil chamber vent valve 12, adjust the boost control valve 14 so that the pressure value of the third pressure sensor 11 increases to 400 kPa in a 50 kPa gradient, and collect the system's pressure, flow rate values ​​and fluctuations at the steady-state pressure point, determine whether the reading of the first flow meter 8 is within the simulated engine's designed lubricating oil circulation range, whether the reading of the third flow meter 29 is within the simulated engine's throttling ventilation lubricating oil chamber nozzle's designed oil supply flow range, and whether the differences between the readings of the first pressure sensor 6, the second pressure sensor 9, the sixth pressure sensor 28 and the third pressure sensor 11 meet the requirements, completely close the boost control valve 14, increase the opening of the throttling ventilation lubricating oil chamber vent valve 12 so that the pressure value of the third pressure sensor 11 decreases to atmospheric pressure in a 50 kPa gradient, and repeat the collection and analysis of the corresponding steady-state point data;

[0052] S4: Adjust the booster control valve 14 and the throttling ventilation lubricating oil chamber vent valve 12, and adjust the pressure value of the third pressure sensor 11 to change rapidly between 100-410KPa (the time taken to increase from the minimum pressure to the maximum pressure or decrease from the maximum pressure to the minimum pressure should not exceed 10s, that is, the time taken to change from 100KPa to 410KPa or from 410KPa to 100KPa should not exceed 10s). Determine whether the system's oil supply flow and pressure meet the requirements and whether the fluctuation has increased. Repeat S4 to verify whether the valve is stuck.

[0053] S5: Fully close the control valve 14, fully open the throttling ventilation lubricating oil chamber vent valve 12, adjust the speed of the oil supply and return pump assembly 15, and collect the flow rate and pressure of the lubricating oil supply system at different speeds.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A simulation test system for a constant differential pressure lubricating oil supply system, characterized in that, The test system includes an oil supply unit for providing a stable pressure oil source, a simulation unit connected to the oil supply unit for simulating the lubricating oil chamber of an aircraft engine, a throttling constant differential pressure regulating valve for adjusting the oil pressure input to the simulation unit, and a test unit for measuring the flow rate and pressure within the simulation unit. The simulation unit includes a throttling ventilation lubricating oil chamber and a free-ventilation lubricating oil chamber. The throttling constant differential pressure regulating valve is located between the oil supply unit and the throttling ventilation lubricating oil chamber. The throttling ventilation lubricating oil chamber is used to simulate the lubricating oil chamber in an aero-engine that requires ventilation and throttling to increase the chamber pressure, while the free-ventilation lubricating oil chamber is used to simulate the lubricating oil chamber in an aero-engine that does not require ventilation and throttling. The throttling and ventilation lubricating oil chamber is equipped with a transparent observation window on the outside and a vent valve on the top. The throttling and ventilation lubricating oil chamber is connected to a pressure boosting control valve and a high-pressure gas cylinder for adjusting the pressure inside the throttling and ventilation lubricating oil chamber. The free-ventilated lubricating oil chamber is connected to the oil outlet of the oil supply unit via a first valve, a third valve, and an equivalent nozzle of the free-ventilated lubricating oil chamber arranged in sequence. The free-ventilated lubricating oil chamber is connected to the lubricating oil tank through a supply and return oil pump assembly to form a return oil circuit. The throttling constant differential pressure regulating valve includes a hollow valve housing. The surface of the valve housing is provided with an oil supply inlet for oil inflow, an oil supply outlet for oil outflow, a cavity pressure sensing inlet for sensing the cavity pressure of the throttling ventilation lubricating oil chamber, and an oil pressure sensing outlet for sensing the oil supply outlet pressure. The hollow cavity of the valve housing is provided with a slide valve for adjusting the outlet flow rate, a spring for providing the pushing force to push the slide valve, and a guide rod and adjusting screw for adjusting the spring compression. The slide valve is provided with a throttling orifice that cooperates with the valve housing to adjust the oil supply flow rate.

2. The constant differential pressure lubricating oil supply system simulation test system according to claim 1, characterized in that, The oil supply unit includes an oil tank for storing lubricating oil, an oil filter located at the oil outlet of the oil tank, and an oil supply and return pump assembly.

3. The constant differential pressure lubricating oil supply system simulation test system according to claim 2, characterized in that, The oil supply and return pump assembly includes a primary oil supply stage and a multi-stage oil return stage rotor gear pump, wherein the primary oil supply stage is equipped with a constant pressure regulating valve.

4. The constant differential pressure lubricating oil supply system simulation test system according to claim 3, characterized in that, The testing unit includes a fourth pressure sensor for measuring the pressure of the lubricating oil tank in the oil supply unit, a temperature sensor for measuring the temperature inside the lubricating oil tank in the oil supply unit, a first pressure sensor for measuring the total oil supply pressure of the oil supply unit, a first flow meter for measuring the total oil supply flow of the oil supply unit, a fifth pressure sensor for measuring the oil supply pressure of the free-ventilation lubricating oil chamber, a second flow meter for measuring the oil supply flow of the free-ventilation lubricating oil chamber, a second pressure sensor for measuring the inlet lubricating oil pressure of the throttling constant differential pressure regulating valve, a sixth pressure sensor for measuring the oil supply pressure of the throttling ventilation lubricating oil chamber, a third flow meter for measuring the oil supply flow of the throttling ventilation lubricating oil chamber, and a third pressure sensor for measuring the cavity pressure of the throttling ventilation lubricating oil chamber.

5. The constant differential pressure lubricating oil supply system simulation test system according to claim 4, characterized in that, The test system also includes a lubricating oil tank vent valve installed on the lubricating oil tank of the oil supply unit for adjusting the pressure of the lubricating oil tank, a vent valve for relieving pressure in the throttling and ventilation lubricating oil chamber, and a second valve installed on the return oil pipeline of the throttling and ventilation lubricating oil chamber.

6. The constant differential pressure lubricating oil supply system simulation test system according to claim 5, characterized in that, The free-ventilation lubricating oil chamber is also provided with a free-ventilation lubricating oil chamber vent.

7. The constant differential pressure lubricating oil supply system simulation test system according to claim 6, characterized in that, The lubricating oil tank is equipped with a heating resistor for heating the lubricating oil.

8. A simulation test method for a constant differential pressure lubricating oil supply system, characterized in that, The test method uses the test system as described in any one of claims 5-7, and includes the following steps: S1: Completely close the boost control valve, heat the lubricating oil in the lubricating oil tank to 80-90℃, adjust the speed of the oil supply and return pump assembly to the speed at the simulated engine design point, then adjust the first valve to ensure that the pressure value of the first pressure sensor is stable to the total oil supply pressure at the simulated engine lubricating oil system design point, and adjust the depth of the lever on the constant pressure regulating valve so that the flow value of the first flow meter reaches the range of the simulated engine's designed lubricating oil circulation volume; S2: Maintain the oil supply and return pump assembly speed at the simulated engine design point speed, adjust the first valve and the third valve so that the pressure values ​​of the first pressure sensor and the second pressure sensor are respectively the total oil supply pressure of the simulated engine lubricating oil system at the design point and the inlet pressure of the throttling constant differential pressure regulating valve. At the same time, ensure that the flow rate of the first flow meter is within the design lubricating oil circulation range of the simulated engine. Then adjust the adjusting screw so that the difference between the pressure value of the sixth pressure sensor and the pressure value of the third pressure sensor is the set working differential pressure of the throttling constant differential pressure regulating valve. At the same time, the flow rate of the third flow meter meets the design oil supply flow rate of the simulated engine throttling ventilation lubricating oil chamber nozzle. S3: Maintain the oil supply and return pump assembly speed at the simulated engine design point speed, adjust the opening of the second valve so that the lubricating oil in the throttling ventilation lubricating oil chamber overflows the return oil pipe opening to create a liquid level, completely close the throttling ventilation lubricating oil chamber vent valve, adjust the boost control valve so that the pressure value of the third pressure sensor increases to 400 kPa in a 50 kPa gradient, and collect the system's pressure, flow rate values ​​and fluctuations at each steady-state pressure point, completely close the boost control valve, increase the opening of the throttling ventilation lubricating oil chamber vent valve so that the pressure value of the third pressure sensor decreases to atmospheric pressure in a 50 kPa gradient, and repeat the collection and analysis of the corresponding steady-state point data; S4: Adjust the booster control valve and the vent valve of the throttling ventilation lubricating oil chamber, adjust the pressure value of the third pressure sensor to vary between 100-410KPa, determine whether the system's oil supply flow and pressure meet the requirements, whether the fluctuation increases, and repeat S4 to verify whether the valve is stuck. S5: Completely close the booster control valve, fully open the throttling ventilation lubricating oil chamber vent valve, adjust the speed of the oil supply and return pump assembly, and collect the flow rate and pressure of the lubricating oil supply system at different speeds.

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