Supersonic constant-speed cruise control method for aviation turbofan engine under hot weather condition

Abstract

The invention belongs to the technical field of aviation turbofan engine control design, and particularly relates to an aviation turbofan engine supersonic constant-speed cruise control method under the hot day condition, which comprises the following steps: step 1, acquiring the inlet temperature T of an aviation turbofan engine under the hot day condition, and the thrust F and the maximum oil consumption rate S required by supersonic constant-speed cruise; secondly, thrust F needed by supersonic constant-speed cruise is kept, the low-pressure rotating speed N1 corresponding to the inlet temperature T of the aviation turbofan engine serves as a starting point, gradual decrease is conducted, the needed thrust augmentation fuel flow W is calculated, and the oil consumption rate s is obtained; and thirdly, when the aviation turbofan engine s is the supersonic constant speed cruise maximum oil consumption rate S, the corresponding low-pressure rotating speed N1 and the thrust augmentation fuel flow W serve as control parameters, thrust augmentation is conducted on the afterburner part, and the aviation turbofan engine is controlled.

Description

Technical Field

[0001] The present application belongs to the technical field of aviation turbofan engine control design, and specifically relates to a method for supersonic cruise control of an aviation turbofan engine under hot weather conditions. Background Art

[0002] Aviation turbofan engines equipped with afterburners usually increase the thrust of the entire aircraft by increasing the engine's low-pressure speed and afterburner fuel flow when flying at high Mach numbers, thereby improving the aircraft's horizontal acceleration performance.

[0003] Some new aircraft have proposed supersonic cruise thrust requirements for aviation turbofan engines without afterburner under standard weather conditions (ground inlet temperature is 15℃, and -56.5℃ above 11km).

[0004] Under hot weather conditions (ground intake temperature is greater than 15°C, greater than -56.5°C above 11km), the inlet temperature of the aviation turbofan engine increases, the air density decreases, and the inlet air flow rate decreases. In order to maintain the thrust required under standard weather conditions, this is currently achieved mostly through the low-pressure speed of the aviation turbofan engine, which often requires a larger low-pressure speed, causing the thermal load of the aviation turbofan engine to approach the design limit, which will seriously damage the service life of the aviation turbofan engine.

[0005] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0006] The purpose of the present application is to provide a method for supersonic cruise control of an aviation turbofan engine under hot weather conditions, so as to overcome or alleviate at least one aspect of the known technical deficiencies.

[0007] The technical solution of this application is:

[0008] A method for controlling supersonic cruise control of an aviation turbofan engine under hot weather conditions, comprising:

[0009] Step 1: Obtain the inlet temperature T of the aviation turbofan engine under hot weather conditions, the thrust F required for supersonic cruise control, and the maximum fuel consumption rate S;

[0010] Step 2: The thrust F required to maintain supersonic cruise speed is calculated by gradually decreasing the low-pressure speed N1 corresponding to the inlet temperature T of the aviation turbofan engine to calculate the required afterburner fuel flow W and obtain the fuel consumption rate s.

[0011] Step 3: When the maximum fuel consumption rate of the aviation turbofan engine s at supersonic cruise is S, the corresponding low-pressure speed N1 and afterburner fuel flow W are used as control parameters to partially afterburn the afterburner combustion chamber and control the aviation turbofan engine.

[0012] According to at least one embodiment of the present application, in the above-mentioned supersonic cruise control method for an aviation turbofan engine under hot weather conditions, in step one, a certain margin is designed to correct the thrust F and maximum fuel consumption rate S required for supersonic cruise control, taking into account the individual differences of aviation turbofan engines and the performance degradation during their entire life cycle.

[0013] According to at least one embodiment of the present application, in the above-mentioned hot weather conditions supersonic cruise control method for an aviation turbofan engine, in step one, the thrust F and maximum fuel consumption rate S required for supersonic cruise are designed to have a margin of X1% and X2%, the thrust F required for supersonic cruise is increased by X1%, and the maximum fuel consumption rate S is reduced by X2%, and the values ​​of X1 and X2 are 2 to 5.

[0014] According to at least one embodiment of the present application, in the above-mentioned method for supersonic cruise control of an aviation turbofan engine under hot weather conditions, in step 2, the low-pressure speed N1 can be decreased in steps of 0.1%.

[0015] According to at least one embodiment of the present application, in the above-mentioned method for supersonic cruise control of an aviation turbofan engine under hot weather conditions, in step 2, the required afterburner fuel flow rate W is calculated based on the overall performance model of the aviation turbofan engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of a method for controlling a supersonic cruise control of an aviation turbofan engine under hot weather conditions provided by an embodiment of the present application;

[0017] Figure 2 It is a schematic diagram of the change of thermal load of an aviation turbofan engine with low-pressure speed provided by an embodiment of the present application;

[0018] Figure 3 It is a schematic diagram of the change of the fuel consumption rate s of an aviation turbofan engine with the low-pressure speed N1 provided in an embodiment of the present application.

[0019] In order to better illustrate the present embodiment, some parts in the drawings may be omitted, which is only used for illustrative purposes and should not be construed as limiting the present application. DETAILED DESCRIPTION

[0020] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0021] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0022] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0023] In practice, the supersonic cruise time of an aviation turbofan engine without afterburner accounts for a relatively small proportion of the total aircraft flight time, and the fuel consumption rate requirements for aviation turbofan engines are relatively low, and they usually have a large fuel consumption rate margin. Although increasing the thrust of an aviation turbofan engine by afterburner combustion can increase the fuel consumption rate, it can reduce the thermal load of the aviation turbofan engine and ensure the service life of the aviation turbofan engine.

[0024] Based on the above, this application proposes a method for supersonic cruise control of an aviation turbofan engine under hot weather conditions, such as Figure 1 As shown, under the condition of maintaining the thrust and fuel consumption requirements under standard day conditions, the thrust of the aviation turbofan engine is increased by increasing the afterburner fuel flow to partially afterburn the afterburner combustion chamber, thereby reducing the low-pressure speed, thereby reducing the thermal load of the aviation turbofan engine and avoiding damage to the service life of the aviation turbofan engine.

[0025] Step 1: Obtain the inlet temperature T of the aviation turbofan engine under hot weather conditions, the thrust F required for supersonic cruise control, and the maximum fuel consumption rate S.

[0026] Under hot weather conditions, the thrust F and maximum fuel consumption rate S required for supersonic cruise of an aviation turbofan engine are obtained based on the results of aircraft-engine coordination.

[0027] Taking into account the individual differences of aviation turbofan engines and the performance degradation during their entire life cycle, a certain margin is designed to correct the thrust F and the maximum fuel consumption rate S required for supersonic cruise control to meet the individual differences of aviation turbofan engines and their use during their entire life cycle. Specifically, the margins of the thrust F and the maximum fuel consumption rate S required for supersonic cruise control can be designed to be X1% and X2%, respectively. The thrust F required for supersonic cruise control is increased by X1%, and the maximum fuel consumption rate S is reduced by X2%. The values ​​of X1 and X2 are 2 to 5.

[0028] Step 2: The thrust F required to maintain supersonic cruise control is gradually reduced from the low-pressure speed N1 corresponding to the inlet temperature T of the aviation turbofan engine to calculate the required afterburner fuel flow W and obtain the fuel consumption rate s.

[0029] To maintain the thrust F required for supersonic cruise control, under hot weather conditions, at different altitudes, the low-pressure speed N1 corresponding to the inlet temperature T of the aviation turbofan engine is not exactly the same, and the low-pressure speed N1 can be decreased in steps of 0.1%.

[0030] The required afterburner fuel flow rate W can be calculated based on the overall performance model of the aviation turbofan engine.

[0031] As the low-pressure speed N1 of the aviation turbofan engine decreases, the turbine pre-temperature T4 of the aviation turbofan engine gradually decreases, that is, the heat load gradually decreases, which helps to improve the life and reliability of the aviation turbofan engine. Figure 2 shown.

[0032] As the low-pressure speed N1 of the aviation turbofan engine decreases, under the condition of equal thrust, more afterburner fuel flow W is required, resulting in an increase in the fuel consumption rate s, such as Figure 3 shown.

[0033] Step 3: When the maximum fuel consumption rate of the aviation turbofan engine s at supersonic cruise is S, the corresponding low-pressure speed N1 and afterburner fuel flow W are used as control parameters to partially afterburn the afterburner combustion chamber and control the aviation turbofan engine.

[0034] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A method for controlling supersonic cruise speed of an aviation turbofan engine under hot weather conditions, characterized in that: include: Step 1: Obtain the inlet temperature T of the aviation turbofan engine under hot weather conditions, the thrust F required for supersonic cruise control, and the maximum fuel consumption rate S; Step 2: The thrust F required to maintain supersonic cruise speed is calculated by gradually decreasing the low-pressure speed N1 corresponding to the inlet temperature T of the aviation turbofan engine to calculate the required afterburner fuel flow W and obtain the fuel consumption rate s. Step 3: When the maximum fuel consumption rate of the aviation turbofan engine s at supersonic cruise is S, the corresponding low-pressure speed N1 and afterburner fuel flow W are used as control parameters to partially afterburn the afterburner combustion chamber and control the aviation turbofan engine.

2. The method for controlling supersonic cruise speed of an aviation turbofan engine under hot weather conditions according to claim 1, characterized in that: In step one, considering the individual differences of aviation turbofan engines and the performance degradation during their entire life cycle, a certain margin is designed to correct the thrust F and maximum fuel consumption rate S required for supersonic cruise control.

3. The method for controlling supersonic cruise speed of an aviation turbofan engine under hot weather conditions according to claim 2, characterized in that: In step 1, the thrust F and maximum fuel consumption rate S required for supersonic cruise control are designed with a margin of X1% and X2%, respectively. The thrust F required for supersonic cruise control is increased by X1%, and the maximum fuel consumption rate S is reduced by X2%. The values ​​of X1 and X2 are 2 to 5.

4. The method for controlling supersonic cruise speed of an aviation turbofan engine under hot weather conditions according to claim 1, characterized in that: In step 2, the low-pressure rotation speed N1 can be decreased in steps of 0.1%.

5. The method for controlling supersonic cruise speed of an aviation turbofan engine under hot weather conditions according to claim 1, characterized in that: In step 2, the required afterburner fuel flow rate W is calculated based on the overall performance model of the aviation turbofan engine.

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