High-power turboprop engine oil interruption test system and method

Abstract

The application discloses a kind of high-power turbofan engine lubricating oil interruption test system and method, including lubricating oil tank, reversing valve, U-shaped pipe section, suction pump and control assembly, lubricating oil tank is used to connect oil return stage, reversing valve is connected with U-shaped pipe section and lubricating oil tank respectively, for connecting outside atmosphere, to carry out oil circuit and air circuit switching, U-shaped pipe section is used to gather lubricating oil, suction pump is connected with U-shaped pipe section, for connecting oil supply stage, to respond time in the switching of reversing valve oil circuit to air circuit, suction lubricating oil in U-shaped pipe section, control assembly is electrically connected with reversing valve and suction pump respectively, for controlling reversing valve and suction pump work;Through lubricating oil tank, reversing valve, U-shaped pipe section, suction pump and control assembly cooperate and cooperate lubricating oil interruption test, compared with prior art, by passive "oil discharge" becomes active "oil suction", realizes complete oil, the accuracy of test result is high, repeatability is good, practicality is strong, is suitable for being widely promoted and application.

Description

Technical Field

[0001] This invention relates to the field of engine airworthiness verification technology, and in particular, to a high-power turboprop engine oil interruption test system. Furthermore, this invention also relates to a high-power turboprop engine oil interruption test method employing the aforementioned high-power turboprop engine oil interruption test system. Background Technology

[0002] In the aviation field, based on the relevant provisions of airworthiness regulations, there are clear requirements for the lubricating oil interruption test for turboprop engines. The test content is: when the engine is running stably at maximum power, the lubricating oil supply to the reduction gearbox and all bearings is suddenly cut off, and the engine is required to not catch fire within a specified time (usually 30 minutes) and to be able to stop safely without posing a danger to the aircraft. This is because the core engine of a turboprop engine rotates at extremely high speeds (tens of thousands of revolutions per minute), while the optimal speed of a propeller is very low (just over a thousand revolutions per minute). A reduction gearbox is needed to reduce the high speed of the core engine to the low speed usable by the propeller. During operation, the reduction gearbox is subjected to enormous torque and mechanical stress. The meshing surfaces of the gears are in high-pressure metal-to-metal contact, requiring an oil film for separation. Furthermore, the power transmission of the reduction gearbox generates a large amount of heat, and oil is its primary, and sometimes only, cooling method. If the oil supply to the reduction gearbox is completely interrupted, there may only be tens of seconds between the onset of an abnormality and a catastrophic failure (gear jamming or breakage). Therefore, an oil interruption test is necessary to ensure that, after complete oil loss, the turboprop engine has sufficient time for the pilot to detect the fault and execute safety procedures, preventing immediate catastrophic consequences. This is especially true for high-power turboprop engines (those with over 5000 shaft horsepower), which need to transmit enormous torque and generate extremely high heat loads during operation, necessitating more advanced technologies to meet this stringent standard of "equality."

[0003] like Figure 1 As shown, the implementation principle of the existing aircraft engine lubricating oil interruption test system is as follows: when the engine is running normally, the two-position three-way valve directs the oil from the fuel pump to the engine inlet; when an interruption is required, the controller sends a signal, the valve core of the two-position three-way valve moves, cuts off the oil supply line of the fuel pump, and at the same time opens the air line, connecting it with the return oil line, that is, the engine oil inlet is connected to the vent to the atmosphere.

[0004] However, the above-mentioned test system has the following drawbacks in actual testing:

[0005] 1) Incomplete oil cut-off: After the valve core of the two-position three-way valve switches, the engine oil inlet line is only exposed to atmospheric pressure. The residual lubricating oil in the line will slowly flow into the engine under the engine's suction action, which cannot achieve complete oil cut-off, resulting in poor accuracy of the test results;

[0006] 2) No residual oil control: After the oil circuit is switched to the air circuit, this method cannot control the residual oil inside the transition section. The amount of residual oil in each test is random and uncontrollable, and the engine inlet pressure is uncontrollable, resulting in poor repeatability.

[0007] 3) Slow valve response: Existing solenoid valves or hydraulically driven valves have long valve core strokes and large masses, and the switching time is usually several hundred milliseconds or even longer, which cannot meet the test requirements for "instantaneous" interruption, and the test results are unreliable;

[0008] 4) Internal leakage of valve: When the valve core of the two-position three-way valve is in the cut-off position, there may be a small amount of internal leakage, which leaks from the fuel supply side to the engine side, contaminating the test results.

[0009] Furthermore, in previous oil interruption tests of turboprop engines conducted on the shaft assembly, the absence of the propeller reduced the impact of the propeller and accessory oil chambers on the engine's lubrication system, allowing the engine oil pressure to remain stable and the oil interruption test to be completed normally. Figure 2 As shown, when a high-power turboprop engine is subjected to an oil interruption test on the propeller stand with the propeller, the oil pressure will be unstable due to the influence of the flow resistance of the propeller and accessory oil chambers and the oil interruption transition section. This will affect the stability of the propeller speed and propeller pitch control. Under these circumstances, the oil interruption test is difficult to carry out normally.

[0010] In summary, existing technologies cannot achieve a truly "complete and instantaneous" interruption of lubricating oil in high-power turboprop engines during lubricating oil interruption tests, and the test results are greatly affected by residual oil, posing significant safety risks. A novel testing system and method are urgently needed to achieve this critical assessment.

[0011] It should be noted that the above background information is only used to assist in understanding the inventive concept and technical solution of the present invention, and it does not necessarily belong to the prior art of the present invention. In the absence of clear evidence that the above content was disclosed on the filing date of the present invention, the above background information should not be used to evaluate the novelty and inventiveness of the present invention. Summary of the Invention

[0012] This invention provides a high-power turboprop engine lubricating oil interruption test system and method to at least solve one technical problem in the prior art.

[0013] According to one aspect of the present invention, a high-power turboprop engine lubrication interruption test system is provided for conducting lubrication interruption tests on a high-power turboprop engine. The high-power turboprop engine includes a supply stage, a propeller assembly, a return stage, and an engine cavity communicating with the supply stage, the propeller assembly, and the return stage respectively. The lubrication interruption test system includes an oil tank, a reversing valve, a U-shaped pipe section, a suction pump, and a control component. The oil tank is used to connect to the return stage. The reversing valve is connected to both the U-shaped pipe section and the oil tank to connect to the outside atmosphere for switching between oil and air circuits. The U-shaped pipe section is used to collect lubrication oil. The suction pump is connected to the U-shaped pipe section to connect to the supply stage so that, within the response time of the reversing valve switching the oil circuit to the air circuit, lubrication oil in the U-shaped pipe section is suctioned. The control component is electrically connected to both the reversing valve and the suction pump to control their operation.

[0014] As a further improvement to the above technical solution:

[0015] Furthermore, the reversing valve includes a valve seat, a valve core disposed within the valve seat, and a piezoelectric ceramic pilot actuator disposed on the valve core. The valve seat is connected to the lubricating oil tank and the U-shaped pipe section respectively to connect to the outside atmosphere. The piezoelectric ceramic pilot actuator is electrically connected to the control component to pilot drive the valve core to move, thereby switching between the oil circuit and the air circuit.

[0016] Furthermore, a sealing ring is provided at the bottom of the valve core, located at the inner cavity interface of the valve seat.

[0017] Furthermore, the valve seat includes an oil inlet connected to the lubricating oil tank, an air inlet for connecting to the outside atmosphere, and an output port connected to the U-shaped pipe section, with the output port and oil inlet arranged coaxially.

[0018] Furthermore, the control components include a valve electronic controller, a pressure sensor, and an engine electronic controller. The valve electronic controller is electrically connected to the reversing valve and is used to send switching commands to the reversing valve. The pressure sensor is used to detect and provide feedback on the lubricating oil pressure in the U-shaped pipe section in real time. The engine electronic controller is electrically connected to the valve electronic controller, the pressure sensor, and the suction pump, respectively. When the lubricating oil pressure fluctuation fed back by the pressure sensor reaches a set value, it sends a switching signal to the valve electronic controller and simultaneously sends a working command to the suction pump.

[0019] Furthermore, the engine electronic controller is also used to electrically connect to the high-power turboprop engine to continuously record key parameters of the high-power turboprop engine after the lubrication is interrupted, and to send a power reduction or shutdown request to the high-power turboprop engine when the key parameters reach preset values.

[0020] Furthermore, a solenoid valve is installed between the U-shaped pipe section and the suction pump. The U-shaped pipe section is connected to the suction pump through the solenoid valve, and the solenoid valve is electrically connected to the control component.

[0021] Furthermore, the lowest point of the U-shaped pipe section is provided with a connection port that connects to the input end of the suction pump.

[0022] Furthermore, a transition structure is provided between the oil tank and the directional valve, and the oil tank is connected to the directional valve through the transition structure.

[0023] According to another aspect of the present invention, a method for testing the lubricating oil interruption of a high-power turboprop engine is also provided, employing the aforementioned high-power turboprop engine lubricating oil interruption test system, comprising the following steps: S1: controlling the high-power turboprop engine to operate stably under a specified power condition; S2: the control component sends a switching command to the reversing valve and simultaneously sends a working command to the suction pump. Within the response time of the reversing valve cutting off the oil circuit and connecting the air circuit, the suction pump operates to drain the lubricating oil in the U-shaped pipe section, so that the inlet pressure of the oil supply stage drops to near absolute vacuum. After the reversing valve switches, the suction pump is controlled to stop working; S3: the control component continuously records the key parameters of the high-power turboprop engine. When the key parameters reach preset values, a power reduction or shutdown request is sent to the high-power turboprop engine; S4: after the specified interruption time of the test, the control component sends a switching command to the reversing valve, which cuts off the air circuit and connects the oil circuit. Then, based on the changes in the recorded key parameters, the working capability of the high-power turboprop engine under lubricating oil interruption conditions is evaluated.

[0024] The present invention has the following beneficial effects:

[0025] The high-power turboprop engine lubrication interruption test system of this invention, during normal oil supply operation, has a reversing valve connected to both the lubrication tank and the U-shaped pipe section. The lubrication oil circulation path is: lubrication tank - reversing valve - U-shaped pipe section - suction pump - oil supply stage - engine cavity - return stage - lubrication tank, with the lubrication oil circulating along the engine cavity - propeller assembly - engine cavity. When lubrication interruption is required, the control component simultaneously sends working commands to both the reversing valve and the suction pump. The reversing valve receives the working command and switches the oil circuit to an air circuit. During the switching response time of the reversing valve, the suction pump works to draw lubrication oil collected in the U-shaped pipe section. After the reversing valve switches the oil circuit to an air circuit, the suction pump has emptied the lubrication oil in the U-shaped pipe section and stopped working, achieving complete oil cut-off, avoiding residual oil management, and ensuring... The inlet pressure of the oil supply tank is reduced to near absolute vacuum to establish a clear and verifiable test benchmark. This ensures that the high-power turboprop engine is not affected by residual oil during the interruption period, improving the accuracy of the test results and meeting the repeatability requirements of the lubrication interruption test. The high-power turboprop engine draws external atmosphere through a suction pump, U-tube section, and reversing valve to conduct the lubrication interruption test within the specified interruption period, thus realizing the airworthiness verification of the high-power turboprop engine's lubrication interruption. This solution conducts the lubrication interruption test through the coordinated operation of the oil tank, reversing valve, U-tube section, suction pump, and control components. Compared with existing technologies, by changing passive "oil discharge" to active "oil suction," a complete oil cutoff is achieved. The test results are highly accurate, repeatable, and practical, making it suitable for widespread promotion and application.

[0026] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0027] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the test principle of an existing aircraft engine lubricating oil interruption test system;

[0029] Figure 2 This is a schematic diagram of the existing turboprop engine lubricating oil interruption test system.

[0030] Figure 3 This is a schematic diagram of the test principle of the high-power turboprop engine lubrication interruption test system according to a preferred embodiment of the present invention;

[0031] Figure 4 This is a partially cutaway structural diagram of the reversing valve in the high-power turboprop engine lubrication interruption test system according to a preferred embodiment of the present invention.

[0032] Legend:

[0033] 110. Oil supply stage; 120. Propeller assembly; 130. Oil return stage; 140. Engine cavity; 210. Oil tank; 220. Reversing valve; 221. Valve seat; 222. Valve core; 223. Oil inlet; 224. Air inlet; 225. Output port; 230. U-shaped pipe section; 240. Suction pump; 251. Valve electronic controller; 260. Adapter structure. Detailed Implementation

[0034] The following description provides specific application scenarios and requirements for this specification, intended to enable those skilled in the art to make and use the contents of this specification. Various partial modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of this specification.

[0035] The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not restrictive. For example, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used herein may also include the plural forms. When used in this specification, the terms “comprising,” “including,” and / or “containing” mean that the associated integers, steps, operations, elements, and / or components are present, but do not preclude the presence of one or more other features, integers, steps, operations, elements, components, and / or groups, or that other features, integers, steps, operations, elements, components, and / or groups may be added to the system / method.

[0036] Considering the following description, these and other features of this specification, as well as the operation and function of the related components of the structure, and the economy of assembly and manufacture of the parts, can be significantly improved. All of these form part of this specification with reference to the accompanying drawings. However, it should be clearly understood that the drawings are for illustrative and descriptive purposes only and are not intended to limit the scope of this specification. It should also be understood that the drawings are not drawn to scale.

[0037] like Figure 3As shown, the high-power turboprop engine oil interruption test system of this embodiment is used to conduct oil interruption tests on a high-power turboprop engine. The high-power turboprop engine includes an oil supply stage 110, a propeller assembly 120, an oil return stage 130, and an engine cavity 140 that communicates with the oil supply stage 110, the propeller assembly 120, and the oil return stage 130 respectively. The oil interruption test system includes an oil tank 210, a reversing valve 220, a U-shaped pipe section 230, a suction pump 240, and control components. The oil tank 210 is used to connect to the oil return stage. Stage 130 and reversing valve 220 are respectively connected to U-shaped pipe section 230 and oil tank 210 to connect to the outside atmosphere for switching between oil and air circuits. U-shaped pipe section 230 is used to collect lubricating oil. Suction pump 240 is connected to U-shaped pipe section 230 to connect to oil supply stage 110 so as to draw lubricating oil in U-shaped pipe section 230 within the response time of reversing valve 220 switching the oil circuit to the air circuit. Control components are electrically connected to reversing valve 220 and suction pump 240 to control the operation of reversing valve 220 and suction pump 240.

[0038] like Figure 3 As shown, specifically, in the high-power turboprop engine lubrication interruption test system of the present invention, during normal oil supply operation, the reversing valve 220 is connected to the lubrication tank 210 and the U-shaped pipe section 230 respectively. The circulation path of the lubrication oil is: lubrication tank 210 - reversing valve 220 - U-shaped pipe section 230 - suction pump 240 - oil supply stage 110 - engine cavity 140 - oil return stage 130 - lubrication tank 210, and the lubrication oil flows along the engine cavity 140 - propeller assembly 1 20- The lubricating oil circulates within the engine cavity 140. When an interruption of lubricating oil is required, the control unit simultaneously sends working commands to the reversing valve 220 and the suction pump 240. The reversing valve 220 receives the working command and switches the oil circuit to the air circuit. During the switching response time of the reversing valve 220, the suction pump 240 works to draw the lubricating oil collected in the U-shaped pipe section 230. This ensures that after the reversing valve 220 switches the oil circuit to the air circuit, the suction pump 240 has already drawn the lubricating oil from the U-shaped pipe section 230. The oil is evacuated and the engine stops operating, achieving complete oil cut-off and avoiding residual oil management. This ensures that the inlet pressure of the oil supply stage 110 drops to near absolute vacuum, establishing a clear and verifiable test baseline. It also ensures that the high-power turboprop engine is not affected by residual oil during the interruption period, improving the accuracy of test results and meeting the repeatability requirements of the lubrication interruption test. The high-power turboprop engine draws external atmosphere through the suction pump 240, U-tube section 230, and reversing valve 220 to conduct the lubrication interruption test within the specified interruption time, achieving airworthiness verification of the high-power turboprop engine's lubrication interruption. This solution uses the coordinated operation of the oil tank 210, reversing valve 220, U-tube section 230, suction pump 240, and control components to conduct the lubrication interruption test. Compared to existing technologies, by changing passive "oil discharge" to active "oil suction," complete oil cut-off is achieved. The test results are highly accurate, repeatable, and practical, making it suitable for widespread promotion and application.

[0039] Optionally, the propeller assembly 120 includes a propeller cavity and accessory oil cavities. Optionally, the engine cavity 140 comprises various engine chambers.

[0040] like Figure 4 As shown, in this embodiment, the reversing valve 220 includes a valve seat 221, a valve core 222 disposed in the valve seat 221, and a piezoelectric ceramic pilot actuator disposed on the valve core 222. The valve seat 221 is connected to the lubricating oil tank 210 and the U-shaped pipe section 230 respectively, for connecting to the outside atmosphere. The piezoelectric ceramic pilot actuator is electrically connected to the control component and is used to pilot drive the valve core 222 to move, so as to switch between the oil circuit and the air circuit. Specifically, the valve core 222 and the piezoelectric ceramic pilot actuator are installed through the valve seat 221. After being connected to the lubricating oil tank 210 and the U-shaped pipe section 230 respectively, and connected to the outside atmosphere, the piezoelectric ceramic pilot actuator can generate micron-level high-precision, high-speed displacement when energized. After receiving the switching command sent by the control component, the piezoelectric ceramic pilot actuator drives the pilot stage oil circuit to control the valve core 222 to move rapidly, thereby quickly switching the oil circuit to the air circuit. This controls the response time of the reversing valve 220 to within 10ms, achieving a true "instantaneous" interruption, meeting the instantaneous interruption test requirements of the lubricating oil interruption test, and improving the reliability of the test results.

[0041] Optionally, the valve core 222 is made of a lightweight material (such as titanium alloy) to greatly reduce moving mass, shorten stroke, and reduce switching time.

[0042] like Figure 3 As shown, in this embodiment, a sealing ring is provided at the bottom of the valve core 222 at the inner cavity interface of the valve seat 221. Specifically, the inner cavity interface of the valve seat 221 is essentially an "interrupted" working position. By providing a sealing ring at the "interrupted" working position, the sealing surface of the valve core 222 and the valve seat 221 form a hard barrier, completely eliminating the possibility of lubricating oil leaking into the air circuit through the inside of the valve core 222 after the oil circuit is switched to the air circuit. This ensures the absolute reliability of the oil circuit switching and avoids contaminating the test results.

[0043] Alternatively, the sealing ring may be made of metal.

[0044] like Figure 4As shown, in this embodiment, the valve seat 221 includes an oil inlet 223 connected to the lubricating oil tank 210, an air inlet 224 for connecting to the outside atmosphere, and an output port 225 connected to the U-shaped pipe section 230. The output port 225 and the oil inlet 223 are coaxially arranged. Specifically, during normal oil supply operation, the output port 225 and the oil inlet 223 are connected. Since the output port 225 and the oil inlet 223 are coaxially arranged, that is, the oil inlet 223 and the output port 225 are in a straight-through direction, pressure fluctuations caused by right-angle turns in the oil circuit are avoided, flow dead zones and pressure losses are reduced, the stability of lubricating oil pressure is improved, and the smooth conduct of lubricating oil interruption tests is facilitated. When the oil circuit is switched to the air circuit, the air inlet 224 and the output port 225 are connected.

[0045] In this embodiment, the reversing valve 220 adopts a dedicated valve design that integrates electromechanical and hydraulic systems. To meet the specific requirement of "instantaneous and complete" interruption, a dedicated valve with integrated piezoelectric ceramic drive, lightweight valve core 222 and hard seal is custom-designed, which solves the performance bottleneck at the actuator end.

[0046] like Figure 3 As shown, in this embodiment, the control components include a valve electronic controller 251, a pressure sensor, and an engine electronic controller. The valve electronic controller 251 is electrically connected to the reversing valve 220 and is used to send a switching command to the reversing valve 220. The pressure sensor is used to detect and feedback the lubricating oil pressure in the U-shaped pipe section 230 in real time. The engine electronic controller is electrically connected to the valve electronic controller 251, the pressure sensor, and the suction pump 240 respectively. When the lubricating oil pressure fed back by the pressure sensor reaches the set value, it sends a switching signal to the valve electronic controller 251 and sends a working command to the suction pump 240.

[0047] like Figure 3As shown, specifically, after the high-power turboprop engine has been running stably at a specified power, the lubricating oil pressure in the U-shaped pipe section 230 is detected and fed back in real time by a pressure sensor. The test personnel can send a lubricating oil interruption command to the control component through the control panel. At this time, the engine electronic controller does not act immediately, but when the lubricating oil pressure fluctuation fed back by the pressure sensor reaches the set value (usually when the lubricating oil pressure fluctuation is the smallest), it sends two commands at the same time point: a switching signal to the valve electronic controller 251 and a working command to the suction pump 240, so as to send a switching signal to the reversing valve 220 through the valve electronic controller 251. During the response time of the reversing valve 220 switching the oil circuit to the air circuit, the suction pump 240 empties the lubricating oil collected in the U-shaped pipe section 230. After the oil circuit switches to the air circuit, the suction pump 240 stops working. In this scheme, during the lubricating oil interruption test, a specific interruption time point is triggered at an opportune time, and it is ensured that this time point is when the lubricating oil pressure fluctuation reaches the set value. This improves or even eliminates the unfavorable factors such as unstable lubricating oil pressure caused by the propeller and accessory oil chambers, poor propeller speed and pitch control stability, etc., during the lubricating oil interruption test of high-power turboprop engines. This is conducive to the smooth conduct of the lubricating oil interruption test and improves the test quality.

[0048] like Figure 3 As shown, in this embodiment, the engine electronic controller is also electrically connected to the high-power turboprop engine to continuously record key parameters of the high-power turboprop engine after oil interruption, and sends a power reduction or shutdown request to the high-power turboprop engine when the key parameters reach preset values. Specifically, the engine electronic controller works with the high-power turboprop engine to achieve safety interlocking. By continuously recording the key parameters of the high-power turboprop engine after oil interruption and issuing preventive requests under specific circumstances, the oil interruption test is elevated to a monitorable and intelligent process, preventing catastrophic damage to the high-power turboprop engine and thus improving the safety of the test.

[0049] In this embodiment, the control component adopts state-aware intelligent control logic, which includes three layers of meaning: opportunistic triggering (sending a command only when the lubricating oil pressure fed back by the pressure sensor reaches the set value), timing coordination (precise synchronization of the reversing valve 220 and the suction pump 240), and safety interlocking (cooperation between the engine electronic controller and the high-power turboprop engine). This transforms the simple "switching action" of the lubricating oil interruption test into a predictable, controllable, and monitorable intelligent process, greatly improving the test quality and safety.

[0050] Optionally, key parameters include engine vibration, turbine after-temperature, and engine speed.

[0051] In this embodiment, a solenoid valve is installed between the U-shaped pipe section 230 and the suction pump 240. The U-shaped pipe section 230 is connected to the suction pump 240 via the solenoid valve, and the solenoid valve is electrically connected to the control component. Specifically, the high-power turboprop engine requires a large amount of lubricating oil for normal operation. The U-shaped pipe section 230 has a large diameter, making it difficult to directly deliver lubricating oil. By gradually increasing the lubricating oil flow rate through the solenoid valve, the difficulty of lubricating oil delivery is reduced, ensuring normal lubricating oil delivery. This allows for normal lubricating oil supply during the preparation phase of the lubricating oil interruption test and the recovery phase after the lubricating oil interruption.

[0052] In this embodiment, the lowest point of the U-shaped pipe section 230 is provided with a connection port that connects to the input end of the suction pump 240. Specifically, the lubricating oil in the U-shaped pipe section 230 gathers towards the lowest point of the U-shaped pipe section 230 under the action of gravity, ensuring that within the response time of the reversing valve 220 switching the oil circuit to the air circuit, the suction pump 240 quickly drains the lubricating oil in the U-shaped pipe section 230 through the connection port using suction force and gravity, avoiding lubricating oil residue and achieving a truly "instantaneous and thorough" interruption of lubricating oil in the high-power turboprop engine.

[0053] like Figure 3 As shown, in this embodiment, a transition structure 260 is provided between the oil tank 210 and the reversing valve 220. The oil tank 210 is connected to the reversing valve 220 through the transition structure 260, so as to accurately simulate the extreme condition of oil interruption safely, reliably and precisely without changing the engine structure. Optionally, the transition structure 260 is a transfer pipe.

[0054] The high-power turboprop engine lubrication interruption test method of this embodiment adopts the above-mentioned high-power turboprop engine lubrication interruption test system, including the following steps: S1: Control the high-power turboprop engine to operate stably under a specified power state; S2: The control component sends a switching command to the reversing valve 220 and a working command to the suction pump 240. Within the response time of the reversing valve 220 cutting off the oil circuit and connecting the air circuit, the suction pump 240 works to drain the lubrication in the U-shaped pipe section 230 so that the inlet pressure of the oil supply stage 110 drops to near absolute vacuum. After the reversing valve 220 switches, the suction pump 240 is controlled to stop working; S3: The control component continuously records the key parameters of the high-power turboprop engine. When the key parameters reach the preset value, the control component sends a lubrication interruption test command to the high-power turboprop engine. The propeller engine sends a power reduction or shutdown request; S4: After the specified interruption time of the test, the control component sends a switching command to the reversing valve 220. The reversing valve 220 cuts off the air circuit and connects the oil circuit. Then, based on the changes in the recorded key parameters, the working capability of the high-power turboprop engine under the lubrication interruption condition is evaluated. Based on the above steps, the passive "oil discharge" is changed to active "oil suction", which realizes complete oil cut-off, avoids residual oil management, and ensures that the inlet pressure of the oil supply stage 110 drops to near absolute vacuum. This establishes a clear and verifiable test benchmark, ensures that the high-power turboprop engine is not affected by residual oil during the interruption time, improves the accuracy of the test results, meets the repeatability requirements of the lubrication interruption test, is highly practical, and is suitable for widespread promotion and application.

[0055] In summary, after reading the detailed disclosure of this specification, those skilled in the art will understand that the foregoing detailed disclosure is presented by way of example only and is not restrictive. Although not explicitly stated herein, those skilled in the art will understand that this specification requires various reasonable changes, improvements, and modifications to the embodiments. These changes, improvements, and modifications are intended to be made by this specification and are within the spirit and scope of the exemplary embodiments described herein.

[0056] Furthermore, certain terms in this specification have been used to describe embodiments of this specification. For example, "an embodiment," "an embodiment," and / or "some embodiments" mean that a particular feature, structure, or characteristic described in connection with that embodiment may be included in at least one embodiment of this specification. Therefore, it is to be emphasized and understood that two or more references to "an embodiment" or "an embodiment" or "alternative embodiment" in various parts of this specification do not necessarily refer to the same embodiment. Moreover, specific features, structures, or characteristics may be suitably combined in one or more embodiments of this specification.

[0057] It should be understood that in the foregoing description of the embodiments in this specification, various features are combined in a single embodiment, drawing, or description for the purpose of simplifying the description and aiding in the understanding of a feature. However, this does not mean that the combination of these features is necessary, and those skilled in the art may readily identify some of the devices as separate embodiments when reading this specification. That is, the embodiments in this specification can also be understood as an integration of multiple secondary embodiments. It is also valid when each secondary embodiment contains fewer than all the features of a single foregoing disclosed embodiment.

[0058] Finally, it should be understood that the embodiments disclosed in this specification are illustrative of the principles of the embodiments described in this specification. Other modified embodiments are also within the scope of this specification. Therefore, the embodiments disclosed in this specification are merely examples and not limitations. Those skilled in the art can implement the applications in this specification using alternative configurations based on the embodiments in this specification. Therefore, the embodiments in this specification are not limited to the embodiments precisely described in the applications.

Claims

1. A high-power turboprop engine lubrication interruption test system for conducting lubrication interruption tests on a high-power turboprop engine, the high-power turboprop engine comprising an oil supply stage (110), a propeller assembly (120), an oil return stage (130), and an engine cavity (140) respectively communicating with the oil supply stage (110), the propeller assembly (120), and the oil return stage (130), characterized in that, The lubricating oil interruption test system includes an oil tank (210), a reversing valve (220), a U-shaped pipe section (230), a suction pump (240), and a control component. The oil tank (210) is used to connect to the return oil stage (130). The reversing valve (220) is connected to the U-shaped pipe section (230) and the oil tank (210) respectively, and is used to connect to the outside atmosphere to switch between the oil circuit and the air circuit. The U-shaped pipe section (230) is used to collect lubricating oil. The suction pump (240) is connected to the U-shaped pipe section (230) and is used to connect to the supply oil stage (110) to draw lubricating oil from the U-shaped pipe section (230) within the response time when the reversing valve (220) switches the oil circuit to the air circuit. The control component is electrically connected to the reversing valve (220) and the suction pump (240) respectively, and is used to control the operation of the reversing valve (220) and the suction pump (240).

2. The high-power turboprop engine lubrication interruption test system according to claim 1, characterized in that, The reversing valve (220) includes a valve seat (221), a valve core (222) disposed in the valve seat (221), and a piezoelectric ceramic pilot actuator disposed on the valve core (222). The valve seat (221) is connected to the lubricating oil tank (210) and the U-shaped pipe section (230) respectively to connect to the outside atmosphere. The piezoelectric ceramic pilot actuator is electrically connected to the control component to pilot drive the valve core (222) to move, so as to switch between oil circuit and air circuit.

3. The high-power turboprop engine lubrication interruption test system according to claim 2, characterized in that, The bottom of the valve core (222) is provided with a sealing ring located at the inner cavity interface of the valve seat (221).

4. The high-power turboprop engine lubrication interruption test system according to claim 2, characterized in that, The valve seat (221) includes an oil inlet (223) connected to the lubricating oil tank (210), an air inlet (224) for connecting to the outside atmosphere, and an output port (225) connected to the U-shaped pipe section (230). The output port (225) and the oil inlet (223) are arranged coaxially.

5. The high-power turboprop engine lubrication interruption test system according to claim 1, characterized in that, The control components include a valve electronic controller (251), a pressure sensor, and an engine electronic controller. The valve electronic controller (251) is electrically connected to the reversing valve (220) and is used to send switching commands to the reversing valve (220). The pressure sensor is used to detect and provide feedback on the lubricating oil pressure in the U-shaped pipe section (230) in real time. The engine electronic controller is electrically connected to the valve electronic controller (251), the pressure sensor, and the suction pump (240) respectively. When the lubricating oil pressure fluctuation fed back by the pressure sensor reaches the set value, the engine electronic controller sends a switching signal to the valve electronic controller (251) and sends a working command to the suction pump (240).

6. The high-power turboprop engine lubrication interruption test system according to claim 5, characterized in that, The engine electronic controller is also used to electrically connect to the high-power turboprop engine to continuously record key parameters of the high-power turboprop engine after the lubrication is interrupted, and to send a power reduction or shutdown request to the high-power turboprop engine when the key parameters reach preset values.

7. The high-power turboprop engine lubrication interruption test system according to any one of claims 1-6, characterized in that, A solenoid valve is installed between the U-shaped pipe section (230) and the suction pump (240). The U-shaped pipe section (230) is connected to the suction pump (240) through the solenoid valve, and the solenoid valve is electrically connected to the control component.

8. The high-power turboprop engine lubrication interruption test system according to any one of claims 1-6, characterized in that, The lowest point of the U-shaped pipe section (230) is provided with a connection port that connects to the input end of the suction pump (240).

9. The high-power turboprop engine lubrication interruption test system according to any one of claims 1-6, characterized in that, A transition structure (260) is provided between the oil tank (210) and the directional valve (220), and the oil tank (210) is connected to the directional valve (220) through the transition structure (260).

10. A method for testing oil interruption in a high-power turboprop engine, characterized in that, The high-power turboprop engine lubrication interruption test system according to any one of claims 1-9 includes the following steps: S1: Controls the high-power turboprop engine to operate stably at a specified power level; S2: The control component sends a switching command to the reversing valve (220) and a working command to the suction pump (240). During the response time of the reversing valve (220) cutting off the oil circuit and connecting the air circuit, the suction pump (240) works to drain the lubricating oil in the U-shaped pipe section (230) so that the inlet pressure of the oil supply stage (110) drops to near absolute vacuum. After the reversing valve (220) switches, the suction pump (240) is controlled to stop working. S3: The control component continuously records the key parameters of the high-power turboprop engine. When the key parameters reach the preset value, it sends a power reduction or shutdown request to the high-power turboprop engine. S4: After the specified interruption time in the test, the control component sends a switching command to the reversing valve (220), which cuts off the air circuit and connects the oil circuit. Then, based on the changes in the recorded key parameters, the working capability of the high-power turboprop engine under the condition of oil interruption is evaluated.

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