Aero-engine surge and stall troubleshooting solution method

Abstract

The invention relates to an aero-engine surge and stall troubleshooting solution, which comprises the following steps of: troubleshooting engine structure damage, namely checking whether an air inlet of an engine is damaged or not, executing engine borescope inspection and confirming the placing position of the engine; checking the wind direction problem of the engine; troubleshooting the problems of the engine system, namely executing an EEC (digital electronic controller) self-checking program to confirm whether fault information exists or not; and checking accessories of an engine, namely checking whether the mounting position of a reverse thrust cascade is correct or not, checking a bleed air system, testing an actuating function of a VSV (adjustable stator blade) / VBV (variable bleed valve) system, and checking / replacing an FMU (fuel metering assembly) and an SCU (fuel distribution assembly). Other associated aspects are also included in the present disclosure.

Description

Technical Field

[0001] The present application generally relates to aircraft engines, and more particularly to solutions for aircraft engine surge and stall. Background Art

[0002] Domestic civilian high-bypass turbofan aircraft engines are still in the critical research and development stage. Surge or stall phenomena are inevitable during the experimental testing phase and the subsequent EIS service process of the product.

[0003] Stall generally refers to the phenomenon that when the compressor speed is constant, if the engine air flow is reduced for some reason, the component of the absolute speed at the working impeller inlet in the direction of the engine axis will decrease, causing the angle of attack to increase. When the angle of attack is too large, the airflow separates at the back of the blade. Surge generally refers to the low-frequency, high-amplitude oscillation of the airflow along the compressor axis.

[0004] Surge and stall of aircraft engines can lead to engine damage and performance degradation. In order to ensure the stable performance and safe and continuous airworthiness of aircraft engines, this application proposes a detailed set of troubleshooting solutions after these phenomena occur, aiming to effectively solve these problems, make the engine performance meet the standards, and thus restore its airworthiness. This not only helps the aircraft engine test verification process to proceed smoothly and restore product performance, but also provides guidance for the compilation of technical publications on aircraft engine troubleshooting. Summary of the invention

[0005] One aspect of the present disclosure relates to a troubleshooting method for aircraft engine surge and stall, comprising the following steps: engine structure damage inspection, including checking whether the engine air inlet is damaged, performing an engine borescope inspection, and confirming the engine placement; engine wind direction problem inspection; engine system problem inspection, including executing the EEC (digital electronic controller) self-test program to confirm whether there is any fault information; and engine accessory inspection, including checking whether the reverse thrust blade installation position is correct, performing an air bleed system inspection, performing a VSV (adjustable stator vane) / VBV (variable bleed valve) system actuation function test, and inspecting / replacing the FMU (fuel metering unit) and SCU (fuel distribution unit).

[0006] According to some exemplary embodiments, the method further comprises performing a recheck, including executing an engine power check test, and if the test result meets the requirements, performing an EEC self-check until no fault information appears; otherwise, returning to the engine system troubleshooting.

[0007] According to some exemplary embodiments, performing an engine borescope inspection includes performing a blower fan unit borescope inspection; inspecting the tail nozzle area for metal debris; and performing a borescope inspection of boost stage blades, high pressure compressor blades, high pressure turbine blades, and low pressure turbine blades.

[0008] According to some exemplary embodiments, engine wind direction troubleshooting is used to ensure that engine surge / stall is not occurring in a crosswind or tailwind condition on the ground, including operating the engine upwind at a thrust level and engine load that produces surge to look for operating issues if a crosswind or tailwind is present.

[0009] According to some exemplary embodiments, an EEC (digital electronic controller) self-test procedure is executed to confirm whether there is any fault information, including if there is any fault information about VSV (adjustable stator vanes), VBV (variable bleed valve), FMV (fuel metering valve), T25, or N2, the relevant fault is corrected and troubleshooted until the fault disappears.

[0010] According to some exemplary embodiments, checking whether the thrust reverser cascade is correctly installed comprises checking whether the cascade on the thrust reverser is correctly installed if surge / stall occurs in the thrust reverse stage; and reinstalling the cascade if the cascade is not correctly installed.

[0011] According to some exemplary embodiments, performing the bleed air system inspection includes inspecting each bleed air valve to ensure that the valve is not damaged and has structural integrity, and that the valve can move smoothly and freely; and if the inspection does not meet the requirements, replacing the bleed air valve.

[0012] According to some exemplary embodiments, performing a VSV / VBV system actuation function test includes performing an actuator function test, including: checking VSV and VBV system hardware during the test; and replacing the VSV or VBV components if a problem is found with the VSV or VBV components.

[0013] According to some exemplary embodiments, performing the actuator function test further comprises executing corrective measures according to fault information if there is no problem with the VSV or VBV component but the actuator function test does not meet the requirements.

[0014] Another aspect of the present disclosure includes a troubleshooting device for aircraft engine surge and stall, including a module for troubleshooting engine structural damage, configured to check whether the engine air inlet is damaged, perform engine borescope inspection, and confirm the engine placement; a module for troubleshooting engine wind direction problems; a module for troubleshooting engine system problems, configured to execute the EEC (digital electronic controller) self-test program to confirm whether there is any fault information; and a module for troubleshooting engine accessories, configured to check whether the reverse thrust blade installation position is correct, perform an air bleed system inspection, perform a VSV (adjustable stator vane) / VBV (variable bleed valve) system actuation function test, and inspect / replace the FMU (fuel metering unit) and SCU (fuel distribution unit).

[0015] Other aspects of the present disclosure also include corresponding devices, equipment, computer-readable media, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram illustrating a solution to aircraft engine surge and stall according to an aspect of the present disclosure is shown.

[0017] Figure 2 Troubleshooting and solutions for aircraft engine surge and stall according to one aspect of the present disclosure are shown.

[0018] Figure 3 A flow chart is shown of troubleshooting and solutions for aircraft engine surge and stall according to one aspect of the present disclosure.

[0019] Figure 4 A flow chart illustrating a troubleshooting method for aircraft engine surge and stall according to an aspect of the present disclosure. DETAILED DESCRIPTION

[0020] Figure 1 A schematic diagram of a solution 100 for aircraft engine surge and stall according to one aspect of the present disclosure is shown. Aircraft engines will inevitably experience surge or stall during the test and testing phase and the subsequent service of new aircraft models (EIS). Since the factors that can cause surge and stall are diverse and the causes are complicated, the troubleshooting and solutions using existing technologies can only rely on experience, and a simple troubleshooting is performed on a single possible cause of the fault at a time, which is prone to omissions and repeated cross-checking, resulting in poor results and a waste of manpower and material resources, and delaying the development of the aircraft engine test verification process.

[0021] To this end, the present invention, based on the analysis of the complex causes of aircraft engine surge and stall, has carefully designed a complete and self-contained set of troubleshooting solutions and devices for aircraft engine surge and / or stall, so as to effectively and efficiently achieve troubleshooting and solutions for aircraft engine surge and / or stall.

[0022] Figure 1 A schematic diagram showing example causes of possible surge and stall of an aircraft engine according to one aspect of the present disclosure is shown. Figure 1 As shown in , the aircraft 100 may include two or more engines 102. The example causes that may cause aircraft engine surge and / or stall are diverse, and there may even be multiple causes acting simultaneously. These example causes include, but are not limited to, engine air inlet damage, engine section damage, engine EEC (digital electronic controller) failure, system actuation function failure, engine placement problem, reverse thrust blade installation problem, bleed air system failure problem, parts and accessories problem and / or other problems, etc. and various combinations thereof. Improper troubleshooting arrangements will lead to difficulty in troubleshooting the cause of the fault, increase troubleshooting difficulty, increase troubleshooting costs, and low troubleshooting efficiency, etc.

[0023] Figure 2 FIG. 2 shows an aircraft engine surge and stall troubleshooting and solution 200 according to an aspect of the present disclosure. Figure 2 As shown in , based on the troubleshooting costs (including expenses, manpower, time, etc.), failure probabilities, troubleshooting logic, etc. associated with various problems, the troubleshooting and solutions 200 for aircraft engine surge and stall disclosed in the present invention may include a structural damage troubleshooting sub-process 202, a wind direction problem troubleshooting sub-process 204, a system problem troubleshooting sub-process 206, and other parts and accessories troubleshooting sub-process 208.

[0024] According to an exemplary embodiment, the structural damage troubleshooting sub-process 202 may include checking whether the engine air intake is damaged. For example, the engine air intake is located at the front end of the engine and needs to inhale a large amount of air at high speed when working. In this process, the engine air intake is likely to be damaged by bird strikes or other foreign objects brought by airflow. In addition, when the aircraft is flying at high speed, due to the adiabatic expansion of the air, the air intake temperature is reduced, which can easily cause ice to form on the edge of the engine air intake, destroying the intake airflow, and seriously causing the engine to stall.

[0025] When signs of damage are found in the engine air intake, a FOD (Foreign Object Damage) inspection may be performed and based on the inspection results a decision may be made to repair / replace (for example, when the FOD inspection result is damage) or to perform a subsequent inspection (for example, when the FOD inspection result is no damage).

[0026] According to an exemplary embodiment, the structural damage troubleshooting subprocess 202 may also include an engine borescope inspection. The inspection location may include various sections of the engine, including but not limited to, for example, the engine fan section, the core section, the tail nozzle section, and the like.

[0027] According to an exemplary embodiment, the borescope inspection of the engine fan section may include inspecting the internal structure of the engine through the reserved exploration hole or ignition nozzle hole on the engine casing without disassembling the engine, using an endoscope, i.e., a borescope, to timely detect damage and evaluate the overall performance of the engine. Borescope inspection can save engine maintenance costs and is also an effective way to monitor the status of the engine on a daily basis.

[0028] Civil aircraft engines, such as turbofan engines and turboprop engines, often include three core components: compressor, combustion chamber and turbine, as well as auxiliary components such as ducts. The core engine mainly includes: high-pressure compressor, combustion chamber and high-pressure turbine. The core engine has a complex structure and harsh working conditions. It is prone to damage such as ablation, blade cracks, and blade tip drop, which may affect the normal operation of the engine. The use of a borescope can achieve in-situ detection without disassembling the engine. Whether there is any damage can be seen more clearly, which helps to correctly judge whether the engine can continue to be used safely.

[0029] In addition to the above-mentioned qualitative observations, borescope inspection can also perform measurements, including defect size measurements and some specific dimensions inside the engine. Defect sizes include: crack length, blade missing angle area, pore depth, etc. These data help to more accurately assess the severity of defects and can also be used to track the development of defects; specific size measurements.

[0030] The results of the borescope inspection may be used to determine whether to repair / replace (for example, when the borescope inspection finds any structural parts are damaged) or to perform a subsequent inspection (for example, when the borescope inspection finds no structural parts are damaged).

[0031] According to an exemplary embodiment, the structural damage troubleshooting sub-process 202 may be followed by a wind direction troubleshooting sub-process 204. The wind direction troubleshooting sub-process 204 may include determining whether the engine surge / stall occurs in a ground crosswind or tailwind condition, and accordingly ensuring that the engine surge / stall does not occur in a ground crosswind or tailwind condition.

[0032] Surge is a special phenomenon in the operation of axial flow fans. The fundamental reason for fan surge is that the outlet pressure and the fan air volume lose correspondence. The outlet pressure is very high and the air volume is very small, causing the fan blades to partially or completely enter the stall zone. When the aircraft is running in low-speed airflow and on the ground, without sufficient or no relative airflow, the engine air inlet will generate a vacuum under the suction of the compressor, causing the engine to stall, and the internal combustion pressure of the engine rushes forward, causing the engine to vibrate and damage the blades.

[0033] In the wind direction troubleshooting sub-process 204 , if a crosswind or tailwind is found to exist, the engine is operated upwind at a thrust level and engine load that produces surge to look for operating problems.

[0034] Whether to perform a subsequent check can be determined based on the result of the wind direction problem troubleshooting subprocess 204 (for example, if there is no crosswind or tailwind, or if there was a crosswind or tailwind and the engine has been operated against the wind, but the surge / stall problem still exists), then a subsequent check is performed.

[0035] According to an exemplary embodiment, wind direction troubleshooting sub-process 204 may be followed by system troubleshooting sub-process 206. System troubleshooting sub-process 206 may include, for example, executing an engine EEC (digital electronic controller) self-test procedure.

[0036] EEC (digital electronic controller) is the core component of the engine digital control system. Its main function is to collect the important control parameters of the engine and control system, process them according to certain control rules and control algorithms, and send control signals to control the relevant actuators, thereby controlling the state of the engine. At the same time, the engine and control system can be monitored and fault diagnosis can be performed based on the collected parameters to protect the safe operation of the engine. EEC (digital electronic controller) can also store relevant working parameters and online fault information of the engine and control system to provide a basis for the maintenance of the engine and control system. EEC can generally include two channels, A and B, but this application is not limited to this.

[0037] According to an exemplary embodiment, the system troubleshooting sub-process 206 performs an engine EEC (digital electronic controller) self-test procedure, which may include checking information about VSV (variable stator vanes), VBV (variable bleed valve), FMV (fuel metering valve), T25, N2 or other faults, etc. If there are problems, these faults are corrected and troubleshooted until these faults disappear.

[0038] Whether to perform a subsequent check may be determined based on the result of the system problem troubleshooting subprocess 206. For example, if the EEC does not have any fault information, a subsequent check may be performed.

[0039] According to an exemplary embodiment, after the system problem troubleshooting sub-process 206, the other parts and accessories troubleshooting sub-process 208 may be performed. According to an exemplary embodiment, the other parts and accessories troubleshooting sub-process 208 may include checking whether the installation position of the thrust reverser cascade is correct, checking the bleed air system, checking the VSV (variable stator vane) and VBV (variable bleed valve) system, and / or checking / replacing the FMU (fuel metering unit) and SCU (fuel distribution unit), etc. or any combination thereof.

[0040] Additionally, the aircraft engine surge and stall troubleshooting and solution 200 may also perform a power check test (not shown), and if the test result meets the requirements, perform an EEC self-check until no fault information appears. Otherwise, the aircraft engine surge and stall troubleshooting and solution 200 returns to the system problem troubleshooting subprocess 206.

[0041] according to Figure 2 An exemplary embodiment of an aircraft engine surge and stall troubleshooting and solution 200 may include, for example, the following steps:

[0042] A. Preparation

[0043] Unplug the A and B channel backup power circuit breakers of the engine EEC to prevent accidents during troubleshooting.

[0044] B. Solution Process

[0045] 1. Check whether the engine air intake is damaged;

[0046] 2. Perform engine borescope inspection, including the engine fan section, core section, and tail nozzle section;

[0047] 3. Confirm the engine placement;

[0048] 4. Perform the EEC self-check procedure to confirm whether there is any fault information;

[0049] 5. Check whether the thrust reverser cascade is installed in the correct position;

[0050] 6. Carry out inspection of air bleed system;

[0051] 7. Carry out VSV / VBV system actuation function test;

[0052] 8.Replace FMU and SCU.

[0053] C. Review

[0054] Repeat the check until no fault message appears.

[0055] According to a further exemplary embodiment, the specific steps of the above workflow may include, but are not limited to, for example, the following work contents:

[0056] 1. Check the engine inlet for bird strikes or foreign objects.

[0057] a) If the above signs are found, perform a FOD (Foreign Object Damage) inspection.

[0058] 1) If the inspection result does not meet the requirements (exceeds the standard) and cannot be repaired, replace the parts.

[0059] 2) If the inspection results do not meet the requirements (exceed the standards), but the engine can be repaired, complete the repair plan.

[0060] 3) If the inspection results meet the requirements (do not exceed the standard), continue to find the cause of surge stall.

[0061] b) If none of the above signs are found, proceed to step 2.

[0062] 2. Perform an engine surge / stall check as follows.

[0063] a) Perform borescope inspection of the fan unit;

[0064] b) Visually inspect the tail nozzle area for any metal debris;

[0065] c) Borescope inspection of booster blades, high-pressure compressor blades, high-pressure turbine blades, and low-pressure turbine blades;

[0066] If any of the above structural parts are found to be damaged during inspection, the damaged part shall be repaired. If it cannot be repaired, the relevant parts shall be scrapped. If no damage is found during inspection or the damage has been repaired, continue to find the cause.

[0067] 3. Ensure that engine surge / stall does not occur in crosswind or tailwind conditions on the ground.

[0068] a) If a crosswind or tailwind exists, operate the engine into the wind at a thrust level and engine load that produces surge to look for operating problems.

[0069] 1) If there are no other issues, the engine can continue to be serviced and subsequent operation will be monitored.

[0070] 2) If there is a problem, continue.

[0071] b) If there is no crosswind or tailwind, continue.

[0072] 4. Perform the EEC self-test procedure.

[0073] a) If there is any fault information about VSV (Variable Stator Vanes), VBV (Variable Bleed Valve), FMV (Fuel Metering Valve), T25, N2 or other faults, correct these faults until they disappear.

[0074] b) If no fault message appears, continue.

[0075] 5. If surge / stall occurs during reverse thrust, check whether the cascades on the thrust reverser are installed correctly.

[0076] a) If the cascade is not installed correctly, reinstall the cascade;

[0077] b) If the cascades are installed correctly, continue.

[0078] 6. Perform bleed air system inspection

[0079] a) Visually inspect each bleed air valve:

[0080] 1) Ensure that the valve is not damaged and has a complete structure;

[0081] 2) Ensure that the valve can move smoothly and freely.

[0082] b) If the visual inspection does not meet the requirements, replace the bleed air valve.

[0083] 7. Check the VSV and VBV systems

[0084] a) Perform an actuator function test

[0085] 1) Visual inspection of VSV and VBV system hardware is required during the test;

[0086] 2) If any problem is found in the VSV or VBV components, replace these components;

[0087] 3) If there is no problem with the component, but the actuator test process does not meet the requirements, perform corrective measures based on the fault information;

[0088] 4) If there are no problems with the components and the actuator test process meets the requirements, continue.

[0089] 8. Check / replace FMU (Fuel Metering Unit) and SCU (Fuel Distribution Unit).

[0090] According to a further exemplary embodiment, a review may be performed. The review may include performing a power check test, and if the test result meets the requirements, performing an EEC self-check until no fault information appears, otherwise executing step 4.

[0091] Figure 3 A flow chart of troubleshooting and solutions 300 for aircraft engine surge and stall is shown in accordance with an aspect of the present disclosure.

[0092] According to an exemplary embodiment, the troubleshooting and solution 300 for aircraft engine surge and stall begins at block 302 and performs preparations (block 304). For example, according to some exemplary embodiments, the preparations may include unplugging the A and B channel backup power circuit breakers of the engine EEC to prevent accidents during the troubleshooting process.

[0093] After completing the preparations (block 304 ), aircraft engine surge and stall troubleshooting and solutions 300 may proceed to inspect the engine air intake for signs of damage, including, for example, bird strikes or other FOD, and if such signs are found, perform a FOD inspection (block 306 ).

[0094] If the inspection result does not meet the requirements (exceeds the standard), but the engine can be repaired, the repair plan is completed (box 308); or if the FOD inspection result does not meet the requirements (exceeds the standard) and cannot be repaired, the damaged parts are replaced (box 310); or if the inspection result meets the requirements (does not exceed the standard), continue to find the cause of the surge stall (go to box 312).

[0095] According to an exemplary embodiment, the troubleshooting and solution 300 for aircraft engine surge and stall may include performing an engine surge / stall check (block 312). The engine surge / stall check (block 312) may, for example, include but is not limited to the following steps:

[0096] a) Perform borescope inspection of the fan unit;

[0097] b) visually inspect the exhaust nozzle area for metal debris; and

[0098] c) Borescope inspection of booster blades, high-pressure compressor blades, high-pressure turbine blades, and low-pressure turbine blades;

[0099] In block 314, it is determined whether any structural component is damaged, for example, as detected by the above inspection. If any of the above structural components are damaged, the damaged part is repaired (block 316). If it cannot be repaired, the relevant parts are scrapped. If no damage is found during the inspection or the damage has been repaired, the cause is continued to be found (go to block 318).

[0100] At block 318 , a downwind / headwind check is performed to ensure that engine surge / stall is not occurring in a ground crosswind or downwind condition.

[0101] At box 320, it is determined whether there is a crosswind or tailwind. If there is a crosswind or tailwind, the engine is changed to run upwind at a thrust level and engine load that produces surge to find the operating problem (box 322) and the aircraft engine surge and stall troubleshooting and solution 300 can go to box 326. Otherwise, if there are no other problems, the engine can continue to be in service and subsequent operation is monitored (box 324). Subsequently, the aircraft engine surge and stall troubleshooting and solution 300 can go to box 326.

[0102] At block 326, the aircraft engine surge and stall troubleshooting and solution 300 may include executing an EEC self-check procedure. According to an exemplary embodiment, the EEC self-check procedure (block 326) may include checking for VSV (Variable Stator Vanes), VBV (Variable Bleed Valve), FMV (Fuel Metering Valve), T25, N2, or other fault information.

[0103] In box 328, it is determined whether the EEC self-test program 326 has any fault information. If fault information is present (box 330), these faults are corrected and troubleshooted until they disappear. The fault information may include, for example, fault information about VSV (variable stator vanes), VBV (variable bleed valve), FMV (fuel metering valve), T25, N2, or other fault information.

[0104] At block 328 , if no fault information is present, the aircraft engine surge and stall troubleshooting and solution 300 proceeds to block 332 .

[0105] At block 332, if surge / stall occurs during the thrust reverse phase, check whether the cascades on the thrust reverser are installed correctly. If the cascades are not installed correctly, reinstall the cascades (block 334). Otherwise, if the cascades are installed correctly, the aircraft engine surge and stall troubleshooting and solution 300 goes to block 336.

[0106] At block 336, aircraft engine surge and stall troubleshooting and solutions 300 performs a bleed air system check. According to an exemplary embodiment, the bleed air system check may include, for example, visually inspecting each bleed air valve to ensure that the valve is not damaged and is structurally intact; ensuring that the valve can move smoothly and freely; and / or any combination thereof.

[0107] At box 338, if the visual inspection is satisfactory, then the aircraft engine surge and stall troubleshooting and solution 300 goes to box 342. On the other hand, if the visual inspection is not satisfactory, then the bleed air valve is replaced (box 340); then go to box 342.

[0108] At block 342, the aircraft engine surge and stall troubleshooting and solution 300 checks the VSV and VBV systems. Subsequently, at block 344, the aircraft engine surge and stall troubleshooting and solution 300 performs an actuator functional test. According to an exemplary embodiment, the actuator functional test may include, for example, visually inspecting the VSV and VBV system hardware during the test.

[0109] At block 346, it is determined whether the VSV and VBV system hardware meets the requirements. If a problem is found with the VSV or VBV components, the aircraft engine surge and stall troubleshooting and solution 300 goes to block 348 to replace these components; on the other hand, if there is no problem with these components, but the actuator test process does not meet the requirements, corrective measures are performed based on the fault information. Subsequently, the aircraft engine surge and stall troubleshooting and solution 300 goes to block 350.

[0110] At block 346 , if it is determined that the component is not faulty, then the actuator testing process is satisfactory and the aircraft engine surge and stall troubleshooting and solution 300 proceeds to block 350 .

[0111] At box 350, check / replace the FMU (fuel metering unit) and SCU (fuel distribution unit).

[0112] According to a further exemplary embodiment, a review may be performed. The review may include performing a power check test at block 352, and if the test result is satisfactory, performing an EEC self-test (block 354), and determining whether there is a fault message at block 356.

[0113] At block 356 , if a fault message is present, aircraft engine surge and stall troubleshooting and solution 300 returns to block 330 to perform fault correction.

[0114] At block 356 , if no fault information is present, then aircraft engine surge and stall troubleshooting and solution 300 ends (block 358 ).

[0115] Figure 4 A flow chart of a method 400 for troubleshooting aircraft engine surge and stall according to an aspect of the present disclosure is shown. The method 400 may include inspecting an engine air intake for damage at block 402 .

[0116] According to an exemplary embodiment, checking the engine air intake for damage in box 402 may include checking the engine inlet for bird strikes or other foreign objects. If the above signs are found, perform a FOD (Foreign Object Damage) check. If the inspection result does not meet the requirements (exceeds the standard) and cannot be repaired, replace the parts. If the inspection result does not meet the requirements (exceeds the standard), but the engine can be repaired, complete the repair plan. If the inspection result meets the requirements (does not exceed the standard), continue to find the cause of the surge stall. If the above signs are not found, continue to step 404.

[0117] The method 400 may further include performing an engine borescope inspection at block 404. For example, the inspection locations may include, but are not limited to, the engine fan section, the core section, the tail nozzle section, and the like.

[0118] The engine borescope check step 404 may include performing an engine surge / stall check as follows.

[0119] a) Perform borescope inspection of the fan unit;

[0120] b) Visually inspect the tail nozzle area for any metal debris;

[0121] c) Borescope inspection of booster blades, high-pressure compressor blades, high-pressure turbine blades, and low-pressure turbine blades;

[0122] If any of the above structural parts are found to be damaged during inspection, the damaged part shall be repaired. If it cannot be repaired, the relevant parts shall be scrapped. If no damage is found during inspection or the damage has been repaired, continue to find the cause.

[0123] Method 400 may further include confirming engine placement at block 406 .

[0124] The engine placement confirmation step 406 may include ensuring that engine surge / stall is not occurring in a crosswind or tailwind condition on the ground. If a crosswind or tailwind is present, run the engine upwind at a thrust level and engine load that produces surge to look for operational issues. If there are no other issues, the engine may remain in service and subsequent operations monitored. If there is an issue, continue. If there is no crosswind or tailwind, continue.

[0125] The method 400 may further include executing an EEC self-checking procedure at block 408 to confirm whether there is any fault information.

[0126] Step 408 of the EEC self-check procedure may include, if there is a fault message about VSV (Variable Stator Vanes), VBV (Variable Bleed Valve), FMV (Fuel Metering Valve), T25, N2 or other faults, then correcting these faults until these faults disappear. If there is no fault message, then continue.

[0127] The method 400 may further include checking whether the thrust reverser cascade installation position is correct at block 410 .

[0128] Step 410 of checking whether the thrust reverser cascade is correctly installed may include checking whether the cascade on the thrust reverser is correctly installed if surge / stall occurs in the thrust reverse stage. If the cascade is not correctly installed, reinstall the cascade; if the cascade is correctly installed, continue.

[0129] The method 400 may further include performing a bleed air system check at block 412 .

[0130] The system check step 412 may include performing a bleed air system check, visually inspecting each bleed air valve to ensure that the valve is not damaged and is structurally intact, and / or ensuring that the valve can move smoothly and freely. If the visual inspection does not meet the requirements, the bleed air valve is replaced.

[0131] The method 400 may further include performing a VSV / VBV system actuation functional test at block 414 .

[0132] The VSV / VBV system actuation function test step 414 may include performing an actuator function test and visually inspecting the VSV and VBV system hardware during the test. If a VSV or VBV component is found to have a problem, replace the component; if the component is fine but the actuator test process does not meet the requirements, perform corrective actions based on the fault information; if the component is fine and the actuator test process meets the requirements, continue.

[0133] The method 400 may further include inspecting / replacing the FMU and the SCU at block 416 .

[0134] The method 400 may further include performing a review at block 418 .

[0135] The review step 418 may include performing a power check test. If the test result meets the requirements, the EEC self-check is performed until no fault information appears, otherwise the steps 408-418 are executed in a loop.

[0136] As a set of effective and complete countermeasures for engine surge and stall, the scheme, system, method and device disclosed in the present invention can effectively solve the problems of surge and stall of aircraft engines that may cause engine damage and performance degradation, make the engine performance meet the standards, and thus restore its airworthiness.

[0137] The scheme, system, method and device disclosed in the present invention can be applied in the engine development and test phase to effectively isolate the engine surge and stall faults during the test process, promote the smooth development of engine project research and development, and can also be applied to the compilation of technical publications on engine troubleshooting, laying a solid foundation for the engine's airworthiness certification.

[0138] The above description is only an exemplary embodiment of the present invention. However, the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention.

[0139] The various illustrative logical blocks, modules, and circuits described in conjunction with the present disclosure may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0140] The steps of the method or algorithm described in conjunction with the present disclosure may be implemented directly in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in any form of storage medium known in the art. Some examples of usable storage media include random access memory (RAM), read-only memory (ROM), flash memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, and the like. The software module may include a single instruction, or many instructions, and may be distributed over several different code segments, distributed between different programs, and distributed across multiple storage media. A storage medium may be coupled to a processor so that the processor can read and write information from / to the storage medium. Alternatively, a storage medium may be integrated into a processor.

[0141] The methods disclosed herein include one or more steps or actions for achieving the described methods. These method steps and / or actions may be interchangeable with each other without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions may be changed without departing from the scope of the claims.

[0142] The processor can execute software stored on a machine-readable medium. The processor can be implemented with one or more general and / or special processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuit systems that can execute software. Software should be broadly interpreted as meaning instructions, data, or any combination thereof, whether it is called software, firmware, middleware, microcode, hardware description language, or other. As an example, a machine-readable medium may include RAM (random access memory), flash memory, ROM (read-only memory), PROM (programmable read-only memory), EPROM (erasable programmable read-only memory), EEPROM (electrically erasable programmable read-only memory), registers, disks, optical disks, hard drives, or any other suitable storage media, or any combination thereof. The machine-readable medium may be implemented in a computer program product. The computer program product may include packaging materials.

[0143] In a hardware implementation, the machine-readable medium may be a part of a processing system that is separate from the processor. However, as will be readily appreciated by those skilled in the art, the machine-readable medium or any part thereof may be external to the processing system. As an example, the machine-readable medium may include a transmission line, a carrier modulated by data, and / or a computer product separate from the wireless node, all of which may be accessed by the processor via a bus interface. Alternatively or in addition, the machine-readable medium or any part thereof may be integrated into the processor, such as a cache and / or a general register file may be the case.

[0144] The processing system can be configured as a general processing system having one or more microprocessors providing processor functionality and external memory providing at least a portion of the machine-readable medium, all linked together with other supporting circuitry via an external bus architecture. Alternatively, the processing system can be implemented with an ASIC (Application Specific Integrated Circuit) with a processor, bus interface, user interface (in the case of an access terminal), supporting circuitry, and at least a portion of the machine-readable medium integrated in a single chip, or with one or more FPGAs (field programmable gate arrays), PLDs (programmable logic devices), controllers, state machines, gating logic, discrete hardware components, or any other suitable circuitry, or any combination of circuits capable of performing the various functionalities described throughout this disclosure. Those skilled in the art will recognize how to best implement the functionality described with respect to the processing system, depending on the specific application and the overall design constraints imposed on the overall system.

[0145] The machine-readable medium may include several software modules. These software modules include instructions that cause a processing system to perform various functions when executed by a device (such as a processor). These software modules may include a transmission module and a reception module. Each software module may reside in a single storage device or be distributed across multiple storage devices. As an example, when a triggering event occurs, a software module may be loaded into a RAM from a hard drive. During the execution of the software module, the processor may load some instructions into a cache to increase access speed. One or more cache lines may then be loaded into a general register file for execution by the processor. When the functionality of a software module is described below, it will be understood that such functionality is implemented by the processor when the processor executes instructions from the software module.

[0146] If implemented in software, each function can be stored on or transmitted by one or more instructions or codes on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and these media include any media that facilitate the transfer of a computer program from one place to another. Storage media can be any available media that can be accessed by a computer. As an example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage devices, or any other media that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (such as infrared (IR), radio, and microwave), the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (such as infrared, radio, and microwave) is included in the definition of the medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Disks, where disks often reproduce data magnetically, and discs reproduce data optically with lasers. Thus, in some aspects, computer-readable media may include non-transitory computer-readable media (e.g., tangible media). Additionally, for other aspects, computer-readable media may include transient computer-readable media (e.g., signals). Combinations of the above should also be included within the scope of computer-readable media.

[0147] Thus, some aspects may include a computer program product for performing the operations presented herein. For example, such a computer program product may include a computer-readable medium having stored (and / or encoded) thereon instructions that can be executed by one or more processors to perform the operations described herein. In some aspects, a computer program product may include packaging materials.

[0148] It will be understood that the claims are not limited to the precise configuration and components illustrated above. Various changes, substitutions and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

1. A troubleshooting method for aircraft engine surge and stall, comprising sequentially performing: Engine structural damage inspection, including checking the engine air intake for damage, performing engine borescope inspection, and confirming the engine placement; Troubleshooting of engine wind direction problems; Engine system troubleshooting, including executing the EEC (digital electronic controller) self-test procedure to confirm whether there is any fault information; as well as Check the engine accessories, including checking whether the thrust reverser blades are installed in the correct position, checking the bleed air system, performing VSV (adjustable stator vanes) / VBV (variable bleed valve) system actuation function test, and checking / replacing the FMU (fuel metering unit) and SCU (fuel distribution unit).

2. The method of claim 1, further comprising conducting a review, comprising: Perform an engine power check test, and If the test results meet the requirements, perform EEC self-test until no fault information appears; Otherwise return to the engine system troubleshooting.

3. The method of claim 1 , wherein performing an engine borescope inspection comprises: Perform borescope inspection of the fan unit; Check the tail nozzle area for any metal debris; as well as And borescope inspection of booster stage blades, high-pressure compressor blades, high-pressure turbine blades, and low-pressure turbine blades.

4. The method of claim 1, wherein the engine wind direction problem troubleshooting is used to ensure that engine surge / stall does not occur in a ground crosswind or tailwind state, comprising: If a crosswind or tailwind exists, run the engine into the wind at a thrust level and engine load that produces surge to look for operating problems.

5. The method of claim 1, wherein executing an EEC (digital electronic controller) self-test program to confirm whether there is any fault information comprises: If a fault message about VSV (Variable Stator Vanes), VBV (Variable Bleed Valve), FMV (Fuel Metering Valve), T25, or N2 appears, correct the related fault until the fault disappears.

6. The method of claim 1, wherein checking whether the thrust reverser cascade is installed in a correct position comprises: If surge / stall occurs during reverse thrust, check whether the cascades on the thrust reverser are installed correctly; as well as If the cascade is not installed correctly, reinstall the cascade.

7. The method of claim 1, wherein performing a bleed air system inspection comprises: Check each bleed air valve to ensure that it is not damaged and is structurally intact, and that it can move freely and smoothly; as well as If the inspection is not satisfactory, the bleed air valve is replaced.

8. The method of claim 1, wherein performing a VSV / VBV system actuation function test comprises performing an actuator function test, comprising: Check VSV and VBV system hardware during testing; as well as If a problem is found with a VSV or VBV component, the VSV or VBV component is replaced.

9. The method of claim 8, wherein: Performing an actuator function test further includes: If there is no problem with the VSV or VBV components, but the actuator function test does not meet the requirements, corrective measures are performed based on the fault information.

10. A troubleshooting device for aircraft engine surge and stall, comprising: A module for engine structural damage investigation, configured to check the engine air intake for damage, perform an engine borescope inspection, and confirm engine placement; Module for troubleshooting engine wind direction issues; A module for troubleshooting engine system problems, configured to execute the EEC (digital electronic controller) self-test procedure to confirm whether there is any fault information; as well as A module used for troubleshooting engine accessories, configured to check whether the thrust reverser blades are correctly installed, perform bleed air system checks, perform VSV (adjustable stator vanes) / VBV (variable bleed valve) system actuation function tests, and check / replace FMU (fuel metering unit) and SCU (fuel distribution unit).

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