A method for on-line monitoring of engine vectoring nozzle function

Abstract

The application belongs to the field of online monitoring of nozzles, and is a kind of online monitoring method for engine vector nozzle function. In view of the main problems of lack of existing vector nozzle state online monitoring method and low recognition rate, the engine main machine aerodynamic parameters are collected, the monitoring mark is established, the engine main machine aerodynamic parameters are mainly introduced, the influence law of key parameters such as binary vector nozzle mechanical area, effective flow area and vector angle on the aerodynamic characteristics of the main machine is considered, the initial state matrix and the diagnosis state matrix are designed, the binary vector nozzle fault judgment is carried out through the area closed loop control judgment logic, the aerodynamic closed loop control judgment logic and the nozzle fault recognition logic, and the binary vector nozzle state monitoring method based on the engine supercharging ratio and other main machine aerodynamic characteristics is recognized. The vector function failure fault mode that cannot be recognized by the traditional electrical monitoring is effectively recognized, and the use safety and maintainability are greatly improved.

Description

Technical Field

[0001] This application belongs to the field of online nozzle monitoring, and specifically relates to an online monitoring method for engine vector nozzle function. Background Technology

[0002] Fighter jets equipped with two-dimensional thrust vectoring engines possess control torques in two directions, enabling them to perform high angle-of-attack post-stall maneuvers that conventional aircraft cannot. However, high angle-of-attack maneuvers in the post-stall region are highly risky, and maintaining flight attitude is heavily dependent on the lateral thrust of the vectoring nozzle. This places high demands on the precision and stability of the vectoring nozzle's state control. Therefore, it is necessary to monitor the state of the vectoring nozzle during high-risk experimental use of the vectoring function to promptly identify nozzle deviations, mechanical failures, or malfunctions, ensuring safe over-vectoring flight.

[0003] Current two-dimensional vector engines lack effective methods for monitoring the status of their two-dimensional vector nozzles. They control the nozzle solely based on preset geometric relationships, typically only checking whether the sensors are functioning correctly. This approach relies on the control status of a single mechanism according to preset geometric relationships. The main drawback of this approach is that the motion actuators of the vector nozzles are complex, and the adjustment of area / angle is achieved through the combined motion of numerous mechanical structures. Monitoring the electrical characteristics of a single actuator cannot take into account all moving and stationary parts. Therefore, it is possible that various failure modes, such as control hardware jamming, breakage, disengagement, and deformation, cannot be identified, potentially leading to other serious consequences.

[0004] Therefore, how to achieve more effective monitoring of two-dimensional vector nozzles is a problem that needs to be solved. Summary of the Invention

[0005] The purpose of this application is to provide an online monitoring method for engine vector nozzle functions, in order to solve the problem that existing two-dimensional vector nozzle monitoring methods basically lack the function of monitoring the status of nozzle control hardware.

[0006] The technical solution of this application is: an online monitoring method for engine vector nozzle function, comprising:

[0007] Collect the aerodynamic parameters of the engine host and establish monitoring indicators. The aerodynamic parameters of the engine include height H, Mach number M, inlet temperature T1, inlet pressure P1, throttle lever status PLA, engine nozzle throat area A8, and nozzle outlet area A9. Set the monitoring indicator judgment threshold to judge whether the monitoring indicator is valid. If it is not valid, it means that an external control command has been issued. If it is valid, it means that no external control command has been issued.

[0008] When the monitoring flag is activated, status monitoring of the engine vector nozzle is initiated, and motion state parameters under at least two different states are recorded to obtain the status monitoring results, which include throat area, main control state parameters, turbine pressure ratio, and vector angle.

[0009] The area closed-loop control judgment logic and the aerodynamic closed-loop control judgment logic are set separately. Based on the throat area and the turbine pressure ratio, the area closed-loop control judgment logic and the aerodynamic closed-loop control judgment logic are used to judge whether the two-dimensional vector nozzle has a fault and obtain a fault judgment result.

[0010] Set up nozzle fault identification logic, perform vector angle fault identification and judgment through vector angle, determine whether the binary vector nozzle has a fault, and obtain secondary fault judgment result;

[0011] Based on the results of the first and second fault assessments, a two-dimensional vector nozzle failure signal is output and sent to the flight control system for processing.

[0012] Preferably, when an external control command is received, including a change / adjustment command, the monitoring flag is determined to be invalid (JKBS = 0) for 10 seconds.

[0013] If no external control command is received, further assess the engine status and record the initial status, which should include the main control commands. The criteria for judging the load on the monitoring indicators are as follows:

[0014] The rate of change α of the engine's transient state parameters is as follows:

[0015]

[0016] In the formula, πt is the engine pressure ratio, the subscript DEM represents the control command given; Ar is the vector nozzle area ratio; δ represents the nozzle vector deflection angle;

[0017] When α ≤ [0.05 0.005 0.5 0.5 0.53 50 0.5 0.052], the monitoring flag is valid, and JKBS = 1.

[0018] Preferably, the specific method for obtaining the status monitoring results is as follows:

[0019] First, record the state matrix at time t, denoted as the initial state matrix; then record the state matrix for the nth control cycle, denoted as the diagnostic state matrix.

[0020] The initial state matrix is ​​the parameter matrix at time t:

[0021] X (t) =[n L ,n H,T3,T6,P3,P6,P8,P9…pif,pic,pit,pie] T时刻

[0022] The diagnostic state matrix is ​​the parameter matrix after n control cycles:

[0023] X (t+n) =[n L ,n H ,T3,T6,P3,P6,P8,P9...pif,pic,pit,pie] T+n时刻

[0024] In the formula, n L nH is the physical speed of the low-pressure rotor of the engine, nH is the physical speed of the high-pressure rotor of the engine, T3 and P3 are the total air temperatures at the compressor outlet and turbine outlet, P3, P6, P8 and P9 are the total gas pressures at the compressor outlet, turbine outlet, nozzle inlet and nozzle outlet, pif is the fan boost ratio, pic is the high-pressure compressor boost ratio, pit is the engine pressure drop ratio, and pie is the nozzle pressure drop ratio.

[0025] Preferably, the area closed-loop control judgment logic is as follows:

[0026] Determine whether the change in laryngeal area A8 exceeds X% and whether the sudden change in the master control parameter exceeds X%; if so, proceed to the next step.

[0027] After the main control parameters and throat area A8 are restored, compare the changes in speed and boost ratio in the diagnostic state matrix and the initial state matrix. If the conditions are met... This means that the throat control hardware has failed;

[0028] in,

[0029]

[0030] Preferably, the pneumatic closed-loop control judgment logic is as follows:

[0031] Determine if the closed-loop control cannot be recovered after a sudden change in the turbine pressure ratio Pit; if so, proceed to the next step.

[0032] Determine if the turbine pressure ratio Pit changes by more than 0.XX, and if the main control status parameters switch or the main control parameters change by more than X%; if so, proceed to the next step.

[0033] After restoring closed-loop control, compare the parameters in the diagnostic state matrix and the initial state matrix, including A8, P3, P6, and T6, to determine whether the conditions are met. If so, it is immediately determined that the throat control hardware has failed;

[0034] in,

[0035]

[0036] Preferably, the specific method for identifying and judging vector angle faults is as follows:

[0037] Determine whether there is no change before and after A8 and whether the vector deflection angle δ J The change is ±0.5°, and the change in the main parameters of the host is ±0.5%; if so, proceed to the next step of judgment.

[0038] The engine's common operating point changes, and whether the relevant parameters in the diagnostic state matrix and the initial state matrix are satisfied is determined. If so, then a vector hardware failure has occurred;

[0039] in,

[0040]

[0041] This application presents an online monitoring method for engine vector nozzle function. Addressing the main problems of existing online monitoring methods for vector nozzle status, such as lack of accuracy and low recognition rate, this method primarily considers incorporating engine mainframe aerodynamic parameters. Based on the influence of key parameters such as the mechanical area, effective flow area, and vector angle of the two-dimensional vector nozzle on the mainframe aerodynamic characteristics, an initial state matrix and a diagnostic state matrix are designed. This two-dimensional vector nozzle status monitoring method, based on engine boost ratio and other mainframe aerodynamic characteristics, effectively identifies vector function failure modes that traditional electrical monitoring methods cannot recognize, significantly improving operational safety and maintainability. Attached Figure Description

[0042] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0043] Figure 1 This is a schematic diagram of the overall process of this application. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] An online monitoring method for engine vector nozzle function is proposed. By observing the sudden changes and trends of aerodynamic parameters, the method aims to monitor the status of the vector nozzle and determine whether the two control function modules, throat area control and vector angle (area ratio) control, have failed.

[0046] The monitoring principle is as follows:

[0047] Under normal conditions, the throat area of ​​the two-dimensional nozzle is mainly controlled based on parameters such as inlet temperature, engine speed, and turbine pressure ratio or engine boost ratio. However, when the mechanism performing the control function fails due to mechanical failures such as jamming, breakage, or severe deformation, the original aerodynamic matching relationship is broken, resulting in a sudden change in aerodynamic parameters. The engine operating point and aerodynamic parameters are then rematched, which is mainly reflected in the following parameters: high and low pressure rotor boost ratio and pressure relationship, temperature rise ratio, and high and low pressure slip.

[0048] Similarly, the deflection angle of the vector engine is mainly controlled based on the preset geometric relationship of the motion mechanism. When a failure occurs, the vector angle changes abruptly. Although the angle feedback value does not change, the effective flow area A8e changes due to the deviation of the actual vector angle. This leads to a phenomenon where the control area A8 remains unchanged, but the aerodynamic parameters change similar to the throat area change.

[0049] Therefore, during the operation of the vector engine, by recording and capturing the instantaneous changes in parameters and the characteristics of parameter changes after rematching, fault judgment criteria can be designed to identify vector function failure problems behind parameter mutations and changes in matching relationships, and online status monitoring of vector angles can be carried out.

[0050] like Figure 1 As shown, the specific steps include:

[0051] Step S100: Perform monitoring identifier judgment.

[0052] Collect the aerodynamic parameters of the main engine and establish monitoring indicators. These parameters include altitude H (aircraft flight altitude, representing the engine's operating altitude), Mach number M (aircraft speed, determining engine inlet operating conditions), inlet temperature T1 (total air temperature at the engine inlet, related to non-standard atmospheres under a given Mach number M), inlet pressure P1 (total air pressure at the engine inlet, related to non-standard atmospheres under a given Mach number M), throttle position PLA (engine throttle position, an input parameter determining engine power status), engine nozzle throat area A8 (engine vector nozzle throat area, an important parameter determining the engine's common operating point), and nozzle exit area A9. Set monitoring indicator judgment thresholds to determine if the monitoring indicator is valid. If it is invalid, it indicates an external control command has been issued; if it is valid, it indicates no external control command has been issued.

[0053] The monitoring identifier has the function of monitoring the status under the comparison / discrimination benchmark conditions. It mainly shields changes in external conditions (such as aircraft bleed air, hydraulic / electric loading, weapon launch) and changes in external control commands of the engine, and mainly judges the status by changes in the engine status matrix.

[0054] When an external control command is issued, including a change / adjustment command, the monitoring flag is determined to be invalid (JKBS = 0) for 10 seconds.

[0055] If no external control command is received, further assess the engine status and record the initial status, which should include the main control commands. The criteria for judging the load on the monitoring indicators are as follows:

[0056] The rate of change α of the engine's transient state parameters is as follows:

[0057]

[0058] The newly added parameters in the formula include: πt is the engine pressure ratio, which can characterize the work done by the high and low pressure rotors of the engine; the subscript DEM represents the given control command, the same below; Ar is the vector nozzle area ratio, which is the ratio of the nozzle exit area to the throat area, and determines the nozzle expansion; δ represents the nozzle vector deflection angle.

[0059] When α ≤ [0.05 0.005 0.5 0.5 0.53 50 0.5 0.052], the monitoring flag is set, JKBS = 1, and monitoring begins.

[0060] Step S200: Perform diagnostic state matrix judgment.

[0061] When the monitoring flag is activated, status monitoring of the engine vector nozzle begins. Motion state parameters are recorded under at least two different states to obtain the status monitoring results, including throat area, main control state parameters, turbine pressure ratio, and vector angle. Specifically: first, the state matrix at time t is recorded, denoted as the initial state matrix; then, the state matrix of the nth control cycle is recorded, denoted as the diagnostic state matrix. Motion state parameters include the aerodynamic parameters of the engine's main cross-sections and their boost (deboost) ratios, as well as other auxiliary judgment parameters such as engine speed and temperature.

[0062] The initial state matrix is ​​the parameter matrix at time t:

[0063] X (t) =[n L ,n H ,T3,T6,P3,P6,P8,P9...pif,pic,pit,pie] T时刻

[0064] The [diagnostic status matrix] is the parameter matrix after n control cycles:

[0065] X (t+n) =[n L ,n H ,T3,T6,P3,P6,P8,P9...pif,pic,pit,pie] T+n时刻

[0066] In the formula, n L nH is the physical speed of the low-pressure rotor of the engine, nH is the physical speed of the high-pressure rotor of the engine, T3 and P3 are the total air temperatures at the compressor outlet and turbine outlet, P3, P6, P8 and P9 are the total gas pressures at the compressor outlet, turbine outlet, nozzle inlet and nozzle outlet, pif is the fan boost ratio, pic is the high-pressure compressor boost ratio, pit is the engine pressure drop ratio, and pie is the nozzle pressure drop ratio.

[0067] Step S300: Perform throat area control monitoring and fault identification.

[0068] ① Area closed-loop control judgment logic

[0069] When the throat area A8 is under closed-loop control at the specified area, a sudden change in the throat area will occur immediately upon mechanical failure. This will be accompanied by a sudden change in the engine's main control parameters (e.g., high / low pressure converted speed). The engine will then re-match and restore the main control parameters according to the control plan. Simultaneously, the area recovery control plan will be adjusted, and a new set of engine state parameters will be matched. By identifying the proportion of parameter changes, it is possible to determine whether the two-dimensional vector nozzle has malfunctioned, as detailed below:

[0070] a) Determine whether the change in the laryngeal area A8 exceeds X%, while simultaneously controlling the main parameter (N). L or N H Does the mutation rate exceed X%? If so, proceed to the next step.

[0071] b) After the main control parameters and laryngeal area A8 are restored, compare the speed and boost / deboost ratio (pic, pif, pit, pie, n) in the diagnostic state matrix and the initial state matrix. 非主控 ) and other changes, such as satisfying This indicates a failure of the throat control hardware.

[0072] Where [K] n ] = f n (A8,η,σ,C f This is the fault coefficient matrix, which takes different values ​​according to different fault modes (because the characteristic changes caused by the failure modes are different, it is necessary to quantitatively correlate them with the aerodynamic parameter change characteristics and give the coefficients), in the following form:

[0073]

[0074] For example, the [K] corresponding to a bracket detachment fault is [0.00X 0.00X 0.00X 0.0X0.00X]. X is a fixed value, such as 5, which can be adjusted according to the requirements of different types of two-dimensional vector nozzles.

[0075] ② Pneumatic closed-loop control judgment logic:

[0076] When the throat area is under closed-loop control of other relevant aerodynamic parameters, the area is uncertain, so faults need to be identified through indirect comparison. For example, if the throat area is controlled by the turbine pressure ratio Pit, a failure will first cause a change in Pit. At the same time, the control system will quickly adjust the area to restore closed-loop control and maintain pit = pitdem (it may not be able to recover, in which case a failure can be determined if no sensor failure has occurred). Based on whether the engine main control channel parameters have switched and the A8 value has changed, it is determined whether the two-dimensional vector nozzle has a fault, as follows:

[0077] a) Determine if a sudden change in the turbine pressure ratio Pit (or other non-area parameters under closed-loop control, the same below) prevents the recovery of closed-loop control; if so, proceed to the next step.

[0078] b) Determine if the turbine pressure drop ratio (Pit) changes by more than 0.XX, and simultaneously check the main control status parameters.

[0079] If a switch occurs (such as N or T6) or a sudden change in the main control parameter exceeds X%, proceed to the next step of judgment.

[0080] c) After restoring closed-loop control, compare the following parameters in the diagnostic state matrix and the initial state matrix.

[0081] Given (A8, P3, P6, T6), determine if the condition is met. If so, it is immediately determined that the throat control hardware has failed.

[0082] [K n ] = f n (A8,η,σ,C f The fault coefficient matrix () differs from area closed-loop control in that it primarily identifies the synchronous changes in the A8 area and the aerodynamic parameter matching relationship, and takes the following form:

[0083]

[0084] Step S400: Perform vector angle monitoring and vector angle fault identification.

[0085] If no abnormality in the throat area is detected based on the above monitoring, vector angle control can be monitored based on this state. Since the vector angle is a direct control quantity, the main identification parameter is a situation where the angle remains constant but the main aerodynamic parameters of the nozzle change abruptly, as detailed below:

[0086] a) Determine if there is no change before and after A8 and if the vector deflection angle δ is... J Maintain stability (within ±0.5°), main parameters of the host (N) H If P3) shows no significant change (e.g., ±0.5%), proceed to the next step.

[0087] b) Changes in the engine's common operating point are determined by checking whether the following parameters (deltan, pif, pic) in the diagnostic state matrix and the initial state matrix are satisfied. if,

[0088] This means that a vector (expansion segment) hardware failure has occurred.

[0089] The corresponding judgment matrix [K] n The following is a function relating the effective flow area and vector angle of the nozzle:

[0090]

[0091] Step S500: Output monitoring results

[0092] Based on the above steps, a two-dimensional vector nozzle failure signal (vector nozzle hardware may fail * fault code (1~n)*) is output and sent to the flight control system for processing.

[0093] This application addresses the main problems of existing online monitoring methods for vector nozzle status, such as lack of accuracy and low recognition rate. It proposes a method that primarily considers incorporating engine mainframe aerodynamic parameters. Based on the influence of key parameters such as the mechanical area, effective flow area, and vector angle of the two-dimensional vector nozzle on the mainframe aerodynamic characteristics, an initial state matrix and a diagnostic state matrix are designed. This method, based on engine boost ratio and other mainframe aerodynamic characteristics, effectively identifies vector function failure modes that traditional electrical monitoring methods cannot recognize, significantly improving operational safety and maintainability.

[0094] Finally, it should be noted that the accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0095] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An engine vectoring nozzle function on-line monitoring method, characterized in that, The application relates to a method for monitoring a binary vector nozzle of an engine, and belongs to the technical field of engine control. The method comprises the following steps: Collecting engine main engine aerodynamic parameters, establishing a monitoring identifier, and the engine aerodynamic parameters including height H, Mach number M, inlet temperature T1, inlet pressure P1, throttle lever state PLA, engine nozzle throat area A8, and nozzle outlet area A9; Setting a monitoring identifier judgment threshold value, judging whether the monitoring identifier is established or not, if not, indicating that an external control instruction appears; if yes, indicating that no external control instruction appears; When the monitoring identifier is established, starting to perform state monitoring on the engine vector nozzle, recording motion state parameters in at least two different states respectively, obtaining a state monitoring result, and the state monitoring result including the throat area, the main control state parameter, the turbine pressure ratio and the vector angle; Respectively setting area closed-loop control judgment logic and aerodynamic closed-loop control judgment logic, judging whether the binary vector nozzle appears a fault or not through the area closed-loop control judgment logic and the aerodynamic closed-loop control judgment logic respectively according to the throat area and the turbine pressure ratio, obtaining a first fault judgment result; Setting a nozzle fault identification logic, judging whether the binary vector nozzle appears a fault or not through vector angle fault identification judgment according to the vector angle, obtaining a second fault judgment result; 2. The method of claim 1, wherein Outputting a binary vector nozzle failure signal according to the first fault judgment result and the second fault judgment result, and sending the binary vector nozzle failure signal to a flight control system for processing. The specific acquisition method of the state monitoring result is as follows: Firstly, recording a state matrix at t moment, and marking the state matrix as an initial state matrix; recording a state matrix of an n control period, and marking the state matrix as a diagnosis state matrix; X (t) = [n L , n H , T3, T6, P3, P6, P8, P9... pif, pic, pit, pie] T时刻 The initial state matrix is a parameter matrix at t moment: X (t+n) = [n L , n H , T3, T6, P3, P6, P8, P9... pif, pic, pit, pie] T+n时刻 where n L is the engine low pressure rotor physical speed, n H is the engine high pressure rotor physical speed, T3, T6 are the air total temperatures at the compressor exit and turbine exit, P3, P6, P8, P9 are the gas total pressures at the compressor exit, turbine exit, nozzle inlet, nozzle exit, pif is the fan pressure ratio, pic is the high pressure compressor pressure ratio, pit is the turbine pressure drop ratio, pie is the nozzle pressure drop ratio.

3. The method of claim 2, wherein the engine vectoring nozzle function is monitored on-line. The diagnosis state matrix is a parameter matrix after n control periods: The area closed-loop control judgment logic is as follows: After the main control parameters and the throat area A8 are restored, the changes of the rotating speed and the boost ratio in the comparative diagnosis state matrix and the initial state matrix are compared. If the following conditions are met That is, the throat control hardware fails. Judging whether the throat area A8 changes by more than X% and whether the main control parameter mutates by more than X% or not; if yes, the next step is judged; 4. The method of claim 2, wherein the engine vectoring nozzle function is monitored on-line. The aerodynamic closed-loop control judgment logic is as follows: Judging whether the turbine pressure ratio Pit mutates and cannot restore closed-loop control or not; if yes, the next step is judged; Judging whether the turbine pressure ratio Pit changes by more than 0.XX and whether the main control state parameter switches or the main control parameter mutates by more than X% or not; if yes, the next step is judged; After the closed-loop control is resumed, parameters in the comparative diagnosis state matrix and the initial state matrix, including A8, P3, P6 and T6, are compared to determine whether the following conditions are met If yes, it is determined that the laryngeal passage control hardware fails; The specific method of the vector angle fault identification judgment is as follows:

5. The method of claim 2, wherein, The specific method of the vector angle fault identification judgment is as follows: determining whether or not the A8 pre-and-post change has not occurred and the vector deflection angle δ J If the variation is ±0.5° and the main parameter variation of the host computer is ±0.5%, the next step is determined. The engine common working point changes, and whether the condition is satisfied is judged through relevant parameters in the diagnosis state matrix and the initial state matrix If yes, the vector hardware fails. ​

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