Engine thrust vectoring nozzle function online monitoring method

Abstract

The invention belongs to the field of nozzle online monitoring, and relates to an engine thrust vectoring nozzle function online monitoring method, which aims at the main problems of lack and low recognition rate of the existing thrust vectoring nozzle state online monitoring method, and comprises the following steps of: acquiring pneumatic parameters of an engine main engine, establishing a monitoring identifier, and introducing the pneumatic parameters of the engine main engine into main consideration. An initial state matrix and a diagnosis state matrix are designed based on the influence law of key parameters such as the mechanical area, the effective flow area and the vector angle of the two-dimensional thrust vectoring nozzle on the aerodynamic characteristics of a main engine, and two-dimensional thrust vectoring nozzle fault judgment is conducted through area closed-loop control judgment logic, pneumatic closed-loop control judgment logic and nozzle fault recognition logic. The invention discloses a two-dimensional thrust vectoring nozzle state monitoring method based on recognition of main engine aerodynamic characteristics such as engine supercharge ratio. Vector function failure fault modes which cannot be recognized by traditional electrical monitoring are effectively recognized, and use safety and maintainability are greatly improved.

Description

Technical Field

[0001] The present application belongs to the field of online monitoring of nozzles, and in particular to an online monitoring method for engine vector nozzle functions. Background Art

[0002] Fighters equipped with dual thrust vectoring engines have control torques in two directions and can therefore perform high-angle-of-attack post-stall maneuvers that conventional aircraft cannot. However, at the same time, high-angle-of-attack maneuvers in the post-stall zone are risky and the flight attitude and other aspects are highly dependent on the lateral thrust of the vector nozzle, which places high demands on the state control accuracy and stability of the vector nozzle. Therefore, it is necessary to monitor the state of the vector nozzle during the use of the high-risk test vector function to promptly identify nozzle state deviations, mechanical failures or failures to ensure the safety of post-vector flight.

[0003] The current binary vector engine does not have a good binary vector nozzle status monitoring method. The nozzle is only controlled based on a preset geometric relationship. Usually, it only judges whether the sensor is working properly, that is, it relies on the control situation of a single mechanism to make a judgment according to the preset geometric relationship. The main disadvantages of this scheme are: the motion actuator of the vector nozzle is complex, and the adjustment of the area / angle is achieved by the combined movement of more mechanical structures. The monitoring of the electrical characteristics of a single actuator cannot take into account all moving parts and stationary parts. Therefore, various failure modes such as control hardware jamming, breakage, disengagement, deformation, etc. may not be identified, which may further lead to other serious consequences.

[0004] Therefore, how to achieve more effective monitoring of binary 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 function, so as to solve the problem that the existing binary vector nozzle monitoring method basically does not have the status monitoring function of the nozzle control hardware.

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

[0007] Collect the aerodynamic parameters of the engine main engine and establish a monitoring mark. The engine aerodynamic related parameters include altitude H, Mach number M, inlet temperature T1, inlet pressure P1, throttle lever state PLA, engine nozzle throat area A8, nozzle outlet area A9; set the monitoring mark judgment threshold to judge whether the monitoring mark is established. If not, it means that an external control instruction has appeared; if established, it means that no external control instruction has appeared;

[0008] When the monitoring mark is established, the engine vector nozzle is started to perform state monitoring, and the motion state parameters in at least two different states are recorded respectively to obtain the state monitoring results, which include the throat area, the main control state parameter, the turbine pressure ratio and the vector angle;

[0009] The area closed-loop control judgment logic and the pneumatic closed-loop control judgment logic are respectively set, and according to the throat area and the turbine drop pressure ratio, the area closed-loop control judgment logic and the pneumatic closed-loop control judgment logic are respectively used to judge whether the binary vector nozzle has a fault, and a fault judgment result is obtained;

[0010] Setting up nozzle fault identification logic, performing vector angle fault identification and judgment through vector angle, judging whether the binary vector nozzle has a fault, and obtaining a secondary fault judgment result;

[0011] A binary vector nozzle failure signal is output based on the primary fault judgment results and the secondary fault judgment results and sent to the flight control system for processing.

[0012] Preferably, when an external control instruction appears, the external control instruction includes a change / adjustment instruction, then it is determined that the monitoring flag is not established JKBS=0, which lasts for 10 seconds;

[0013] When no external control command appears, further judge the engine status, record the initial status should include the main control command, the judgment standard of monitoring mark bearing capacity is as follows:

[0014] The engine transition state parameter change rate ɑ is as follows:

[0015]

[0016] In the formula, πt is the engine pressure drop 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 ɑ≤[0.050.0050.50.50.53500.50.052] is satisfied, the monitoring flag is established and JKBS=1.

[0018] Preferably, the specific method for obtaining the status monitoring result is:

[0019] First, record the state matrix at time t, which is recorded as the initial state matrix; record the state matrix of the nth control cycle, which is recorded 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] Where n L is the physical speed of the engine low-pressure rotor, nH is the physical speed of the engine high-pressure rotor, T3 and P3 are the total air temperatures at the compressor outlet and turbine outlet, P3, P6, P8, P9 are the total gas pressures at the compressor outlet, turbine outlet, nozzle inlet, and nozzle outlet, pif is the fan pressure ratio, pic is the high-pressure compressor pressure ratio, pit is the engine drop pressure ratio, and pie is the nozzle drop pressure ratio.

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

[0026] Determine whether the throat area A8 changes by more than X% and whether the main control parameter mutation exceeds X%; if so, proceed to the next step of determination;

[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 That is, there is a throat control hardware failure;

[0028] in,

[0029]

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

[0031] Determine whether the closed-loop control cannot be restored after the turbine pressure ratio Pit suddenly changes; if so, proceed to the next step of determination;

[0032] Determine whether the turbine pressure drop ratio Pit changes by more than 0.XX, and at the same time the main control state parameter switches or the main control parameter changes by more than X%; if so, proceed to the next step of determination;

[0033] After the closed-loop control is restored, the parameters in the diagnostic state matrix and the initial state matrix, including A8, P3, P6 and T6, are compared to determine whether they meet If so, it is determined that the throat control hardware fails;

[0034] in,

[0035]

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

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

[0038] The common operating point of the engine changes, and the relevant parameters in the diagnostic state matrix and the initial state matrix are used to determine whether the If so, vector hardware failure occurs;

[0039] in,

[0040]

[0041] The engine vector nozzle function online monitoring method of this application aims at the main problems of the lack of existing vector nozzle status online monitoring methods and low recognition rate. By mainly considering the introduction of engine main engine aerodynamic parameters, based on the influence of key parameters such as binary vector nozzle mechanical area, effective flow area, vector angle on the main engine aerodynamic characteristics, the initial state matrix and diagnostic state matrix are designed, and the binary vector nozzle status monitoring method based on the recognition of main engine aerodynamic characteristics such as engine boost ratio is effectively identified. The vector function failure mode that cannot be identified by traditional electrical monitoring is greatly improved, and the use safety and maintainability are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

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

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The invention discloses an online monitoring method for engine vector nozzle function, which realizes the purpose of monitoring the state of the vector nozzle through the mutation and change trend of aerodynamic parameters, and determines whether the two control function modules of throat area control and vector angle (area ratio) control fail.

[0046] The monitoring principle is:

[0047] Under non-fault conditions, the throat area of ​​the two-dimensional nozzle is mainly controlled based on parameters such as the inlet temperature, engine speed and turbine drop pressure ratio or engine boost ratio. However, when the mechanism that performs the control function fails due to mechanical faults such as sticking, breakage, severe deformation, etc., the original aerodynamic matching relationship is broken, resulting in a sudden change in aerodynamic parameters. The engine operating point and aerodynamic parameters are re-matched, which is mainly reflected in the following parameters: the boost ratio and pressure relationship of the high and low pressure rotors, the temperature rise ratio, and the high and low pressure slip.

[0048] Similarly, the deflection angle of the vector engine is mainly controlled according to the preset geometric relationship of the motion mechanism. When failure occurs, the vector angle changes suddenly. Although the angle feedback value does not change, the deviation of the actual vector angle causes the effective flow area A8e to change, resulting in the control area A8 remaining unchanged but the aerodynamic parameter changes similar to the throat area change.

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

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

[0051] Step S100: Determine monitoring mark

[0052] Collect the aerodynamic parameters of the engine main engine and establish monitoring marks. The engine aerodynamic related parameters include altitude H (the pressure altitude of the aircraft flying, indicating the working altitude of the engine), Mach number M (the flight speed of the aircraft, which determines the working conditions of the engine inlet), inlet temperature T1 (the total temperature of the engine inlet air, under the condition of a certain Mach number M, it is related to the non-standard atmosphere), inlet pressure P1 (the total pressure of the engine inlet air, under the condition of a certain Mach number M, it is related to the non-standard atmosphere), throttle lever state PLA (engine throttle lever, an input parameter that determines the engine power state), engine nozzle throat area A8 (engine vector nozzle throat area, an important parameter that determines the common working point of the engine); nozzle outlet area A9. Set the monitoring mark judgment threshold to determine whether the monitoring mark is established. If not, it means that an external control instruction has appeared; if established, it means that no external control instruction has appeared.

[0053] The monitoring mark has the function of performing status monitoring under comparison / judgment benchmark conditions. It mainly shields changes in external conditions (such as aircraft air bleed, hydraulic / electric loading, weapon launch) and changes in external engine control commands, and mainly makes judgments based on changes in the engine status matrix.

[0054] When an external control instruction appears, which includes a change / adjustment instruction, the monitoring flag is judged to be invalid and JKBS=0, which lasts for 10 seconds;

[0055] When no external control command appears, further judge the engine status, record the initial status should include the main control command, the judgment standard of monitoring mark bearing capacity is as follows:

[0056] The engine transition state parameter change rate ɑ is as follows:

[0057]

[0058] The newly added parameters in the formula include: πt is the engine pressure drop 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 outlet area to the throat area, and determines the expansion of the nozzle; δ represents the nozzle vector deflection angle;

[0059] When ɑ≤[0.050.0050.50.50.53500.50.052] is satisfied, the monitoring flag is established, JKBS=1, and monitoring starts.

[0060] Step S200, perform diagnostic status matrix judgment

[0061] When the monitoring flag is established, the engine vector nozzle is started to perform state monitoring, and the motion state parameters in at least two different states are recorded to obtain the state monitoring results, which include throat area, main control state parameters, turbine drop pressure ratio and vector angle, etc. Specifically: first record the state matrix at time t, recorded as the initial state matrix; record the state matrix of the nth control cycle, recorded as the diagnostic state matrix, and the motion state parameters include the aerodynamic parameters of the main cross-section of the engine and its increase (decrease) pressure ratio and other auxiliary judgment parameters such as speed, temperature, etc.

[0062] [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] [Diagnostic state 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] Where n L is the physical speed of the engine low-pressure rotor, nH is the physical speed of the engine high-pressure rotor, T3 and P3 are the total air temperatures at the compressor outlet and turbine outlet, P3, P6, P8, P9 are the total gas pressures at the compressor outlet, turbine outlet, nozzle inlet, and nozzle outlet, pif is the fan pressure ratio, pic is the high-pressure compressor pressure ratio, pit is the engine drop pressure ratio, and pie is the nozzle drop pressure ratio.

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

[0068] ① Area closed-loop control judgment logic

[0069] When the throat area A8 is in the closed-loop control of the specified area, when a mechanical failure occurs, the throat area will suddenly change immediately, accompanied by a sudden change in the engine's main control parameters (such as high and low pressure conversion speed) at the current moment. The engine will re-match and restore the main control parameters according to the control plan. At the same time, the area is adjusted to restore the control plan. The state parameters of the engine will match a new set of parameters. By identifying the parameter change ratio, it can be determined whether the binary vector nozzle has a fault, as follows:

[0070] a) Determine whether the throat area A8 changes by more than X% and the main control parameter (N L or N H ) Whether the mutation exceeds X%; if so, proceed to the next step;

[0071] b) After the main control parameters and throat area A8 are restored, compare the speed and pressure increase (decrease) ratio (pic, pif, pit, pie, n 非主控 ) and other changes, such as meeting That is, throat control hardware failure occurs.

[0072] Among them [K n ] = f n (A8,η,σ,C f ) is the fault coefficient matrix, which takes different values ​​according to different fault modes (due to the different characteristic changes caused by the failure mode, it is necessary to quantitatively associate the coefficients with the characteristics of the aerodynamic parameter changes), and the form is as follows:

[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 binary vector nozzles.

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

[0076] When the throat area is under closed-loop control of other related aerodynamic parameters, since the area is uncertain, it is necessary to identify the fault by indirect comparison. For example, if the throat area is controlled by the turbine pressure ratio Pit, the failure will first lead to the change of Pit. At the same time, the control system quickly adjusts the area to restore the closed-loop control, keeping pit = pitdem (it may not be restored, so it can be determined that the failure has occurred when there is no sensor failure). According to whether the engine main control channel parameters are switched and the change of A8 at this time, it is judged whether the binary vector nozzle has a fault, as follows:

[0077] a) Determine whether the turbine pressure ratio Pit (or other non-area parameters in closed-loop control, the same below) suddenly changes and the closed-loop control cannot be restored; if so, proceed to the next step of determination;

[0078] b) Determine whether the turbine pressure drop ratio Pit changes by more than 0.XX, and the main control state parameters

[0079] (such as N or T6, etc.) switching occurs or the main control parameter mutation exceeds X%; if so, 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] (A8, P3, P6, T6), determine whether If so, it is determined that the throat control hardware has failed.

[0082] [K n ] = f n (A8,η,σ,C f ) is the fault coefficient matrix. Different from the area closed-loop control, it mainly identifies the synchronous changes of the matching relationship between the A8 area and the aerodynamic parameters. The form is as follows:

[0083]

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

[0085] When there is no throat area abnormality according to the above monitoring, the vector angle control can be monitored based on this state. Since the vector angle is a direct control quantity, the main identification parameter is the situation where the angle remains unchanged but the main aerodynamic parameters of the nozzle suddenly change, as follows:

[0086] a) Determine whether there is no front-to-back change of A8 and the vector deflection angle δ J Maintain stability (within ±0.5°), main parameters of the host (N H , P3) No significant change occurs (e.g. ±0.5%); if so, proceed to the next step of judgment;

[0087] b) The common operating point of the engine changes. The following parameters (deltan, pif, pic) in the diagnostic state matrix and the initial state matrix are used to determine whether the following parameters are met: if,

[0088] That is, vector (expansion segment) hardware failure occurs.

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

[0090]

[0091] Step S500: Output monitoring results

[0092] According to the above steps, the binary 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 aims to solve the main problems of the lack of existing online monitoring methods for vector nozzle status and low recognition rate. By mainly considering the introduction of engine main engine aerodynamic parameters, based on the influence of key parameters such as binary vector nozzle mechanical area, effective flow area, vector angle on the main engine aerodynamic characteristics, the initial state matrix and diagnostic state matrix are designed, and a binary vector nozzle status monitoring method based on the recognition of main engine aerodynamic characteristics such as engine boost ratio is proposed. It effectively identifies the vector function failure mode that cannot be identified by traditional electrical monitoring, greatly improving the safety and maintainability of use.

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

[0095] Finally: 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 in the protection scope of the present invention.

Claims

1. A method for online monitoring of engine vector nozzle function, characterized in that: include: Collect the aerodynamic parameters of the engine main engine and establish monitoring marks. The engine aerodynamic related parameters include altitude H, Mach number M, inlet temperature T1, inlet pressure P1, throttle lever state PLA, engine nozzle throat area A8, nozzle outlet area A9; Set the monitoring mark judgment threshold to judge whether the monitoring mark is established. If not, it means that an external control instruction has appeared; if established, it means that no external control instruction has appeared; When the monitoring mark is established, the engine vector nozzle is started to perform state monitoring, and the motion state parameters in at least two different states are recorded respectively to obtain the state monitoring results, which include the throat area, the main control state parameter, the turbine pressure ratio and the vector angle; The area closed-loop control judgment logic and the pneumatic closed-loop control judgment logic are respectively set, and according to the throat area and the turbine drop pressure ratio, the area closed-loop control judgment logic and the pneumatic closed-loop control judgment logic are respectively used to judge whether the binary vector nozzle has a fault, and a fault judgment result is obtained; Setting up nozzle fault identification logic, performing vector angle fault identification and judgment through vector angle, judging whether the binary vector nozzle has a fault, and obtaining a secondary fault judgment result; A binary vector nozzle failure signal is output based on the primary fault judgment results and the secondary fault judgment results and sent to the flight control system for processing.

2. The method for online monitoring of engine vector nozzle function according to claim 1, characterized in that: When an external control instruction appears, which includes a change / adjustment instruction, the monitoring flag is judged to be invalid and JKBS=0, which lasts for 10 seconds; When no external control command appears, further judge the engine status, record the initial status should include the main control command, the judgment standard of monitoring mark bearing capacity is as follows: The engine transition state parameter change rate ɑ is as follows: In the formula, πt is the engine pressure drop ratio, the subscript DEM represents the control command given; Ar is the vector nozzle area ratio; δ represents the nozzle vector deflection angle; When ɑ≤[0.050.0050.50.50.53500.50.052] is satisfied, the monitoring flag is established and JKBS=1.

3. The method for online monitoring of engine vector nozzle function according to claim 1, characterized in that: The specific method for obtaining the status monitoring result is: First, record the state matrix at time t, which is recorded as the initial state matrix; record the state matrix of the nth control cycle, which is recorded as the diagnostic state matrix; The initial state matrix is ​​the parameter matrix at time t: <h2 style=";text-align:left;direction:ltr">X<h2 style=";text-align:left;direction:ltr"> (t) <h2 style=";text-align:left;direction:ltr"> =[n<h2 style=";text-align:left;direction:ltr"> L <h2 style=";text-align:left;direction:ltr"> ,n<h2 style=";text-align:left;direction:ltr"> H <h2 style=";text-align:left;direction:ltr"> [T3,T6,P3,P6,P8,P9...pif,pic,pit,pie]<h2 style=";text-align:left;direction:ltr"> T时刻 The diagnostic state matrix is ​​the parameter matrix after n control cycles: <h2 style=";text-align:left;direction:ltr">X<h2 style=";text-align:left;direction:ltr"> (t+n) <h2 style=";text-align:left;direction:ltr"> =[n<h2 style=";text-align:left;direction:ltr"> L <h2 style=";text-align:left;direction:ltr"> ,n<h2 style=";text-align:left;direction:ltr"> H <h2 style=";text-align:left;direction:ltr"> [T3,T6,P3,P6,P8,P9…pif,pic,pit,pie]<h2 style=";text-align:left;direction:ltr"> T+n时刻 Where n L is the physical speed of the engine low-pressure rotor, nH is the physical speed of the engine high-pressure rotor, T3 and P3 are the total air temperatures at the compressor outlet and turbine outlet, P3, P6, P8, P9 are the total gas pressures at the compressor outlet, turbine outlet, nozzle inlet, and nozzle outlet, pif is the fan pressure ratio, pic is the high-pressure compressor pressure ratio, pit is the engine drop pressure ratio, and pie is the nozzle drop pressure ratio.

4. The method for online monitoring of engine vector nozzle function according to claim 3, characterized in that: The area closed-loop control judgment logic is: Determine whether the throat area A8 changes by more than X% and whether the main control parameter mutation exceeds X%; if so, proceed to the next step of determination; 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 That is, there is a throat control hardware failure; in, 5. The method for online monitoring of engine vector nozzle function according to claim 3, characterized in that: The pneumatic closed-loop control judgment logic is: Determine whether the closed-loop control cannot be restored after the turbine pressure ratio Pit suddenly changes; if so, proceed to the next step of determination; Determine whether the turbine pressure drop ratio Pit changes by more than 0.XX, and at the same time the main control state parameter switches or the main control parameter changes by more than X%; if so, proceed to the next step of determination; After the closed-loop control is restored, the parameters in the diagnostic state matrix and the initial state matrix, including A8, P3, P6 and T6, are compared to determine whether they meet If so, it is determined that the throat control hardware fails; in, 6. The method for online monitoring of engine vector nozzle function according to claim 3, characterized in that: The specific method for identifying and judging the vector angle fault is as follows: Determine whether there is no front-to-back change of A8 and the vector deflection angle δ J The change is ±0.5°, and the change of the main parameters of the host is ±0.5%; if so, proceed to the next step; The common operating point of the engine changes, and the relevant parameters in the diagnostic state matrix and the initial state matrix are used to determine whether the If so, vector hardware failure occurs; in,

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