Design method of engine main fuel control based on slow vehicle state according to flying height matching demand

Abstract

The application belongs to the technical field of engine control design, and particularly relates to a slow-speed state engine fuel control design method based on flight and take-off matching requirements, which distinguishes ground slow-speed state and air slow-speed state, respectively performs main fuel control design, and effectively meets the requirements of aircraft cabin bleed air pressure, aircraft and engine inlet flow matching and engine stable working performance under the whole envelope use condition on the basis of meeting the typical point slow-speed thrust requirement and ensuring normal working of the engine, and is simple and easy to implement.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of engine control design, and particularly relates to a slow-speed state engine fuel control design method based on flight engine matching requirements. BACKGROUND

[0002] When an airplane performs actions such as steady flight deceleration, high-altitude glide, and maneuvering flight, the engine often works in a slow-speed state. The slow-speed state is one of the main working states of the engine, and whether the design is reasonable or not will not only affect the economy, reliability, and safety of the engine, but also affect the safety and maneuverability of the airplane.

[0003] Currently, the design of the main fuel flow control of the engine in the slow-speed state is mostly based on the typical point slow-speed thrust requirement given by the user, to ensure that the engine can work normally, to calculate the relationship curve of the relative physical rotating speed of the high-pressure rotor of the engine in the slow-speed state with the engine inlet temperature, to select the high value from the fuel supply amount required to maintain the relative physical rotating speed of the high-pressure rotor and the minimum fuel flow in the slow-speed state, as the control of the main fuel flow of the engine in the slow-speed state, and to verify and iterate the control of the main fuel flow of the engine in the slow-speed state through bench and flight tests, to finally determine the control of the main fuel flow of the engine in the slow-speed state. This kind of technical scheme is simple and easy to implement.

[0004] In the full envelope range, the engine inlet total temperature and the inlet total pressure vary greatly at different altitudes and Mach numbers. Under different engine inlet total pressures, the low-pressure rotor relative converted rotating speed required to ensure the stable working performance of the engine axial force, each cavity sealing, whole machine vibration, and combustion chamber combustion is different. The main fuel flow control of the engine in the slow-speed state designed by the existing method cannot ensure that the airplane cabin pressure is maintained in the ideal range under the full envelope use condition, and under the supersonic maneuvering flight condition, the engine works in the middle and above state, the inlet air flow is large, the engine throttle lever is quickly pulled to the slow-speed state, the engine inlet air flow is quickly reduced, while the air flow of the airplane inlet duct is still large, the flow is not matched, the airplane inlet duct and the engine surge, and the flight safety is seriously affected.

[0005] The present application is proposed in view of the existence of the above technical defects. SUMMARY

[0006] The purpose of the present application is to provide a slow-speed state engine main fuel control design method based on flight engine matching requirements, to overcome or alleviate at least one aspect of the known technical defects.

[0007] The technical scheme of the present application is:

[0008] A slow-speed state engine fuel control design method based on flight engine matching requirements, comprising a ground slow-speed state engine main fuel control design method and an air slow-speed state engine main fuel control design method.

[0009] The engine main fuel control design method for ground idle state includes:

[0010] S11, determine the standard sea level ground idle state engine low-pressure rotor relative conversion speed n1r_grd_0;

[0011] S12, refer to the standard sea level ground idle state engine low-pressure rotor relative conversion speed n1r_grd_0, determine the low-pressure rotor relative conversion speed n1r_grd_1 required to ensure the stable working performance of the engine under different engine inlet total pressure Pt2 conditions in ground idle state;

[0012] S13, calculate the minimum fuel flow Wf_grd_min required to maintain stable combustion in ground idle state;

[0013] S14, select the minimum fuel flow Wf_grd_min required to maintain n1r_grd_1 as the engine main fuel control in ground idle state;

[0014] The engine main fuel control design method for air idle state includes:

[0015] S21, determine the minimum engine low-pressure conversion speed n1r_air_1 required to meet the aircraft cabin bleed air pressure Pt27 demand under different engine inlet total pressure Pt2;

[0016] S22, refer to the minimum engine low-pressure conversion speed n1r_air_1 required to meet the aircraft cabin bleed air pressure Pt27 demand under different engine inlet total pressure Pt2, determine the low-pressure rotor relative conversion speed n1r_air_2 required to ensure the stable working performance of the engine under different engine inlet total pressure Pt2 conditions in air idle state;

[0017] S23, determine the minimum low-pressure rotor relative conversion speed n1r_air_3 required to maintain stable operation of the aircraft inlet duct during the engine deceleration process from the intermediate state to the idle state under different altitudes H and Mach numbers MA in air idle state;

[0018] S24, calculate the minimum fuel flow Wf_air_min required to maintain stable combustion in air idle state;

[0019] S25, select the minimum fuel flow Wf_air_min required to maintain n1r_air_2, the minimum fuel flow required to maintain n1r_air_3, and the minimum fuel flow Wf_air_min as the engine main fuel control in air idle state.

[0020] According to at least one of the embodiments of the present application, in the above-mentioned engine fuel control design method for slow-speed state based on the matching requirement of flying, the engine main fuel control design method for ground slow-speed state further comprises:

[0021] S15, verifying and correcting the engine main fuel control for ground slow-speed state through ground bench and high-altitude bench tests.

[0022] According to at least one of the embodiments of the present application, in the above-mentioned engine fuel control design method for slow-speed state based on the matching requirement of flying, S11 is specifically:

[0023] According to the given ground slow-speed state thrust requirement of the user, the engine low-pressure rotor relative conversion speed n1r for ground slow-speed state is calculated, and is corrected according to the whole machine test result of the ground bench, the engine inlet total pressure Pt2 is taken as 101.325 kPa, and the standard sea level ground slow-speed state engine low-pressure rotor relative conversion speed n1r_grd_0 is obtained.

[0024] According to at least one of the embodiments of the present application, in the above-mentioned engine fuel control design method for slow-speed state based on the matching requirement of flying, S12 is specifically:

[0025] A plurality of envelope ground state points are selected, the engine overall parameters are calculated according to the standard sea level ground slow-speed state engine low-pressure rotor relative conversion speed n1r_grd_0, whether the engine stable working performance requirement is met is evaluated, if the engine stable working performance requirement cannot be met, the engine low-pressure rotor relative conversion speed is adjusted until the engine stable working performance requirement is met, and the low-pressure rotor relative conversion speed n1r_grd_1 that can ensure the engine stable working performance requirement under different engine inlet total pressures Pt2 of ground slow-speed state is obtained.

[0026] According to at least one of the embodiments of the present application, in the above-mentioned engine fuel control design method for slow-speed state based on the matching requirement of flying, the engine main fuel control design method for air slow-speed state further comprises:

[0027] S26, verifying and correcting the engine main fuel control for air slow-speed state through ground bench and high-altitude bench tests.

[0028] According to at least one of the embodiments of the present application, in the above-mentioned engine fuel control design method for slow-speed state based on the matching requirement of flying, S21 is specifically:

[0029] According to the engine operating envelope, the engine inlet total pressure line is determined, and a plurality of air typical height Mach number points are selected on the same engine inlet total pressure line from small to large. The minimum engine low-pressure conversion speed that meets the aircraft cabin bleed air pressure Pt27 requirement under the same engine inlet total pressure Pt2 is calculated, and the minimum engine low-pressure conversion speed n1r_air_1 that meets the aircraft cabin bleed air pressure Pt27 requirement under different engine inlet total pressures Pt2 in the air is obtained.

[0030] According to at least one embodiment of the present application, in the above-mentioned slow-speed state engine fuel control design method based on the matching requirements of the aircraft and the engine, S22 is specifically:

[0031] A plurality of air typical height Mach number points are selected, and the minimum engine low-pressure conversion speed n1r_air_1 that meets the aircraft cabin bleed air pressure Pt27 requirement under different engine inlet total pressures Pt2 is calculated. The engine overall parameters are calculated, and whether the engine stable working performance requirement is met is evaluated. If the engine stable working performance requirement cannot be met, the relative conversion speed of the engine low-pressure rotor is adjusted until the engine stable working performance requirement is met. The relative conversion speed n1r_air_2 of the low-pressure rotor that guarantees the engine stable working performance requirement under different engine inlet total pressures Pt2 in the air slow-speed state is obtained.

[0032] According to at least one embodiment of the present application, in the above-mentioned slow-speed state engine fuel control design method based on the matching requirements of the aircraft and the engine, S23 is specifically:

[0033] The engine inlet air flow W1 under different altitudes H and Mach numbers MA in the intermediate state is calculated and determined. The minimum engine inlet air flow W1min that can keep the aircraft inlet duct stable working during the engine deceleration process from the intermediate state to the slow-speed state is obtained by combining the simulation calculation of the aircraft inlet duct characteristics. The minimum relative conversion speed n1r_air_3 of the low-pressure rotor that can keep the aircraft inlet duct stable working during the engine deceleration process from the intermediate state to the slow-speed state under different altitudes H and Mach numbers MA in the air slow-speed state is obtained by simulation calculation.

[0034] The present application has at least the following beneficial technical effects:

[0035] A slow-speed state engine main fuel control design method based on the matching requirements of the aircraft and the engine is provided. The ground slow-speed state and the air slow-speed state are distinguished, and the main fuel control design is performed respectively. The aircraft cabin bleed air pressure requirement, the aircraft inlet duct and the engine inlet duct flow matching, and the engine stable working performance requirement under the full envelope use condition can be effectively met on the basis of meeting the typical point slow-speed thrust requirement and guaranteeing the normal working of the engine. The method is simple and easy to implement. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 FIG. 1 is a schematic diagram of a slow-speed state engine main fuel control design method based on the matching demand of a flying vehicle provided by an embodiment of the present application.

[0037] In order to better illustrate the embodiments, some components in the drawings can be omitted, enlarged or reduced, and do not represent the actual size of the product. In addition, the drawings are only used for illustrative description and cannot be understood as a limitation of the present application. DETAILED DESCRIPTION

[0038] In order to make the technical solutions of the present application and its advantages clearer, the technical solutions of the present application will be further clearly and completely described in detail below in combination with the drawings. It should be understood that the specific embodiments described herein are only part of the embodiments of the present application, which are only used to explain the present application, but not to limit the present application. It should be noted that, for the purpose of description, only parts related to the present application are shown in the drawings, and other related parts can be referred to the general design.

[0039] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of the present application should be understood as the general meaning understood by the general technical personnel in the field to which the present application belongs. The words indicating the direction used in the description of the present application are only used to indicate the relative direction or positional relationship, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly. In the description of the present application, "including" indicates that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, and other elements or objects are not excluded.

[0040] In addition, it should be noted that, unless otherwise specified and limited, the "installation", "connection" and similar words used in the description of the present application should be understood in a broad sense, for example, the connection can be fixed connection or detachable connection; can be mechanical connection or electrical connection; can be directly connected or indirectly connected through intermediate medium, and the person skilled in the art can understand the specific meaning of the present application according to the specific circumstances.

[0041] A slow-speed state engine main fuel control design method based on the matching demand of a flying vehicle, including a ground slow-speed state engine main fuel control design method, an air slow-speed state engine main fuel control design method, as shown in Figure 1 .

[0042] The ground slow-speed state engine main fuel control design method includes the following steps:

[0043] S11, determining the standard sea level ground slow-speed state engine low-pressure rotor relative conversion speed n1r_grd_0.

[0044] According to the user given ground idle state thrust demand, the engine ground idle state engine low pressure rotor relative conversion speed n1r is calculated, and is corrected according to the ground bench whole machine test result, the engine inlet total pressure Pt2=101.325kPa is taken, and the standard sea level ground idle state engine low pressure rotor relative conversion speed n1r_grd_0 is obtained.

[0045] S12, referring to the standard sea level ground idle state engine low pressure rotor relative conversion speed n1r_grd_0, the low pressure rotor relative conversion speed n1r_grd_1 required to ensure the stable working performance of the engine under different engine inlet total pressure Pt2 conditions is determined.

[0046] A plurality of envelope ground state points are selected, the engine overall parameters are calculated according to the standard sea level ground idle state engine low pressure rotor relative conversion speed n1r_grd_0, and whether the engine stable working performance needs are met is evaluated, which specifically includes the engine axial force, each cavity sealing, whole machine vibration, combustion chamber combustion and other aspects of the demand, if the engine stable working performance needs cannot be met, the engine low pressure rotor relative conversion speed is adjusted until the engine stable working performance needs are met, the low pressure rotor relative conversion speed n1r_grd_1 required to ensure the stable working performance of the engine under different engine inlet total pressure Pt2 conditions is obtained, and the following table form can be designed:

[0047] Pt2 XXX XXX XXX XXX XXX XXX n1r_grd_1 XXX XXX XXX XXX XXX XXX

[0048] The envelope ground state point, the Mach number MA is 0, and the height H is 0 to the upper limit of the ground state height.

[0049] S13, the minimum fuel flow Wf_grd_min required to maintain stable combustion in the ground idle state is calculated and obtained.

[0050] S14, the minimum fuel flow Wf_grd_min required to maintain stable combustion in the ground idle state is calculated and obtained.

[0051] S15, the ground bench and high altitude bench test are used to verify and correct the ground idle state engine main fuel control.

[0052] The engine main fuel control design method in the air idle state is as follows:

[0053] S21, the minimum engine low pressure conversion speed n1r_air_1 required to meet the aircraft cabin bleed air pressure Pt27 demand under different engine inlet total pressure Pt2 is determined.

[0054] According to the engine operating envelope, the engine inlet total pressure line is determined, generally only the engine inlet total pressure Pt2< 101.325 kPa is needed, from small to large, select several air typical height Mach number points on the same engine inlet total pressure line, calculate the minimum engine low-pressure conversion speed under the condition of the same engine inlet total pressure Pt2 that meets the demand of the aircraft cabin bleed air pressure Pt27, obtain the minimum engine low-pressure conversion speed n1r_air_1 under the condition of different engine inlet total pressure Pt2 in the air that meets the demand of the aircraft cabin bleed air pressure Pt27, which can be designed in the following table form:

[0055]

[0056]

[0057] S22, referring to the minimum engine low-pressure conversion speed n1r_air_1 under the condition of different engine inlet total pressure Pt2 that meets the demand of the aircraft cabin bleed air pressure Pt27, determine the low-pressure rotor relative conversion speed n1r_air_2 required to ensure the stable working performance of the engine under the condition of different engine inlet total pressure Pt2 in the air idle state.

[0058] Select several air typical height Mach number points, calculate the engine overall parameters according to the minimum engine low-pressure conversion speed n1r_air_1 under the condition of different engine inlet total pressure Pt2 that meets the demand of the aircraft cabin bleed air pressure Pt27, evaluate whether it meets the needs of the stable working performance of the engine, which specifically includes the needs of engine axial force, each cavity sealing, whole machine vibration, combustion chamber combustion, etc. If it cannot meet the needs of the stable working performance of the engine, adjust the low-pressure rotor relative conversion speed until it meets the needs of the stable working performance of the engine, and obtain the low-pressure rotor relative conversion speed n1r_air_2 required to ensure the stable working performance of the engine under the condition of different engine inlet total pressure Pt2 in the air idle state.

[0059] S23, determine the minimum low-pressure rotor relative conversion speed n1r_air_3 that can keep the aircraft inlet duct stable working during the deceleration process of the engine from the intermediate state to the idle state under the condition of different height H and Mach number MA in the air idle state.

[0060] The calculation determines that the full envelope line is different height H, Mach number MA, generally only Mach number Ma≥1.0, the intermediate state engine inlet air flow W1, combined with the aircraft inlet duct characteristic simulation calculation, the minimum inlet air flow W1min of the engine that the aircraft inlet duct can keep stable work in the process of engine deceleration from the intermediate state to the slow speed state is obtained, and the minimum low pressure rotor relative conversion speed n1r_air_3 of the engine that the aircraft inlet duct can keep stable work in the process of engine deceleration from the intermediate state to the slow speed state is obtained in the slow speed state in the air at different height H, Mach number MA, and the following table form can be designed:

[0061]

[0062]

[0063] S24, the minimum fuel flow Wf_air_min of the slow speed state in the air is calculated and obtained.

[0064] S25, from the fuel supply amount required to keep n1r_air_2, the fuel supply amount required to keep n1r_air_3, and Wf_air_min, the engine main fuel control in the slow speed state in the air is selected.

[0065] S26, the engine main fuel control in the slow speed state in the air is verified and corrected by ground bench and high altitude test.

[0066] The above embodiment discloses the slow speed state engine main fuel control design method based on the matching requirement of the aircraft, which distinguishes the ground slow speed state and the slow speed state in the air, respectively designs the main fuel control, can effectively meet the aircraft cabin bleed air pressure requirement, aircraft inlet duct and engine inlet duct flow matching and engine stable working performance requirement under the full envelope line use condition on the basis of meeting the typical point slow speed thrust requirement and ensuring the normal working of the engine, and is simple and easy to implement.

[0067] So far, the technical scheme of the application has been described in combination with the preferred embodiments shown in the drawings, and those skilled in the art should understand that the protection scope of the application is obviously not limited to these specific embodiments, and those skilled in the art can make equivalent changes or replacements to related technical features without deviating from the principles of the application, and the technical scheme after the changes or replacements will fall within the protection scope of the application.

Claims

1. A method for designing engine fuel control based on flywheel matching demand for slow vehicle state, characterized in that, The engine main fuel control design method for the ground idle state comprises the following steps: The engine main fuel control design method for the ground idle state comprises the following steps: S11, determining the standard sea level ground idle state engine low-pressure rotor relative conversion speed n1r_grd_0; S12, referring to the standard sea level ground idle state engine low-pressure rotor relative conversion speed n1r_grd_0, determining the low-pressure rotor relative conversion speed n1r_grd_1 required to ensure the stable working performance of the engine under different engine inlet total pressures Pt2 in the ground idle state; S13, calculating the minimum fuel flow Wf_grd_min required to maintain stable combustion in the ground idle state; S14, selecting the fuel supply amount required to maintain n1r_grd_1 and Wf_grd_min as the engine main fuel control in the ground idle state; The engine main fuel control design method for the air idle state comprises the following steps: S21, determining the minimum engine low-pressure conversion speed n1r_air_1 required to meet the aircraft cabin bleed air pressure Pt27 demand under different engine inlet total pressures Pt2; S22, referring to the minimum engine low-pressure conversion speed n1r_air_1 required to meet the aircraft cabin bleed air pressure Pt27 demand under different engine inlet total pressures Pt2, determining the low-pressure rotor relative conversion speed n1r_air_2 required to ensure the stable working performance of the engine under different engine inlet total pressures Pt2 in the air idle state; S23, determining the minimum low-pressure rotor relative conversion speed n1r_air_3 required to maintain stable operation of the aircraft inlet duct during the deceleration process of the engine from the intermediate state to the idle state under different altitudes H and Mach numbers MA in the air idle state; S24, calculating the minimum fuel flow Wf_air_min required to maintain stable combustion in the air idle state; S25, selecting the fuel supply amount required to maintain n1r_air_2, the fuel supply amount required to maintain n1r_air_3, and Wf_air_min as the engine main fuel control in the air idle state.

2. The idle state engine fuel control design method based on the matching requirements of the aircraft and the engine according to claim 1, wherein The engine main fuel control design method for the ground idle state further comprises the following steps: S15, verifying and correcting the engine main fuel control in the ground idle state through ground bench and high-altitude bench tests.

3. The idle state engine fuel control design method based on the matching requirements of the aircraft and the engine according to claim 1, wherein S11 specifically comprises the following steps: According to the user-given thrust demand in the ground idle state, the engine low-pressure rotor relative conversion speed n1r in the ground idle state is calculated, and the standard sea level ground idle state engine low-pressure rotor relative conversion speed n1r_grd_0 is obtained by correcting the ground bench test results and taking the engine inlet total pressure Pt2 = 101.325 kPa.

4. The idle state engine fuel control design method based on the matching requirements of the aircraft and the engine according to claim 1, wherein S12 specifically is: Select several envelope ground state points, according to the standard sea level ground slow running state engine low pressure rotor relative conversion speed n1r_grd_0, calculate the engine overall parameters, evaluate whether to meet the engine stable working performance needs, if not able to meet the engine stable working performance needs, then adjust the engine low pressure rotor relative conversion speed, until meet the engine stable working performance needs, get the ground slow running state different engine inlet total pressure Pt2 conditions, ensure the low pressure rotor relative conversion speed n1r_grd_1 of engine stable working performance needs.

5. The slow running state engine fuel control design method based on the flight engine matching demand according to claim 1, characterized in that, The air slow running state engine main fuel control design method further comprises: S26, with the ground bench and high altitude test, verify and correct the air slow running state engine main fuel control.

6. The slow running state engine fuel control design method based on the flight engine matching demand according to claim 1, characterized in that, S21 specifically is: According to the engine working envelope, calculate and determine the equal engine inlet total pressure line, from small to large, select several air typical height Mach number points on the same engine inlet total pressure line one by one, calculate the minimum engine low pressure conversion speed under the same engine inlet total pressure Pt2 conditions, meet the aircraft cabin bleed air pressure Pt27 demand, obtain the minimum engine low pressure conversion speed n1r_air_1 under different engine inlet total pressure Pt2 conditions in the air, meet the aircraft cabin bleed air pressure Pt27 demand.

7. The slow running state engine fuel control design method based on the flight engine matching demand according to claim 1, characterized in that, S22 specifically is: Select several air typical height Mach number points, according to the minimum engine low pressure conversion speed n1r_air_1 under different engine inlet total pressure Pt2 conditions, meet the aircraft cabin bleed air pressure Pt27 demand, calculate the engine overall parameters, evaluate whether to meet the engine stable working performance needs, if not able to meet the engine stable working performance needs, then adjust the engine low pressure rotor relative conversion speed, until meet the engine stable working performance needs, get the low pressure rotor relative conversion speed n1r_air_2 of air slow running state different engine inlet total pressure Pt2 conditions, ensure the engine stable working performance needs.

8. The slow running state engine fuel control design method based on the flight engine matching demand according to claim 1, characterized in that, S23 specifically is: Calculate and determine the intermediate state engine inlet air flow W1 under different height H, Mach number MA of the whole envelope, combine the aircraft inlet duct characteristic simulation calculation to obtain the minimum engine inlet air flow W1min that the aircraft inlet duct can keep stable working during the engine deceleration process from the intermediate state to the slow running state, simulation calculation obtains the minimum low pressure rotor relative conversion speed n1r_air_3 that the aircraft inlet duct can keep stable working during the engine deceleration process from the intermediate state to the slow running state under different height H, Mach number MA of the air slow running state.

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