A turbine engine acceleration and deceleration fueling method

Abstract

This application belongs to the field of aero-engine design and is a method for fuel supply during acceleration and deceleration of a turbine engine. When the engine is operating, it is first controlled according to the normally designed acceleration and deceleration fuel supply pattern. By setting criteria for slow acceleration and slow deceleration, it is determined whether the engine's acceleration or deceleration is too slow. If the slow acceleration or deceleration criterion is triggered, it indicates that the engine's acceleration or deceleration is too slow, and the current acceleration or deceleration fuel supply pattern is canceled. For engines with slow acceleration, a certain percentage is increased based on the current acceleration fuel supply pattern to increase the engine's acceleration rate; for engines with slow deceleration, a certain percentage is decreased based on the current deceleration fuel supply pattern to increase the engine's deceleration rate. Then, simulation calculations are used to ensure that the new acceleration or deceleration fuel supply pattern has good deceleration performance, thereby effectively solving the problem of slow engine acceleration and deceleration and ensuring stable engine operation.

Description

Technical Field

[0001] This application belongs to the field of aero-engine design, and specifically relates to a fuel supply method for acceleration and deceleration of a turbine engine. Background Technology

[0002] Currently, domestic aero-engines generally use fuel-air ratio control for acceleration and deceleration. This means that during acceleration and deceleration, the engine supplies fuel according to a given acceleration / deceleration fuel-air ratio, thereby achieving acceleration and deceleration control. When controlling engine acceleration and deceleration according to the fuel-air ratio, the following control logic must be followed: current fuel-air ratio > deceleration fuel-air ratio, and current fuel-air ratio < acceleration fuel-air ratio. If the engine can operate stably and has good acceleration and deceleration performance, the steady-state fuel-air ratio should be between the acceleration and deceleration fuel-air ratios with a certain margin.

[0003] Because many factors influence the steady-state fuel-air ratio of an engine (such as engine performance degradation, manufacturing differences, aircraft bleed air, power extraction, errors in fuel-air ratio calculation parameters, flight altitude, and flight speed), the designed acceleration and deceleration fuel-air ratios may not be suitable for all operating conditions. Taking acceleration as an example, if the steady-state fuel-air ratio is close to the acceleration fuel-air ratio, the engine will accelerate more slowly; if the steady-state fuel-air ratio is higher than the acceleration fuel-air ratio, the engine will become unstable, and the engine speed will gradually decrease until the engine stops. Both of these situations will have a very adverse impact on engine performance and safety.

[0004] Therefore, improving the acceleration and deceleration rate of aero engines and ensuring engine stability is a problem that needs to be solved. Summary of the Invention

[0005] The purpose of this application is to provide a fuel supply method for acceleration and deceleration of a turbocharged engine, so as to solve the problem of slow acceleration and deceleration or even unstable state of the engine in the prior art.

[0006] The technical solution of this application is: a fuel supply method for acceleration and deceleration of a turbine engine, comprising: establishing a simulation calculation model, obtaining the acceleration and deceleration state parameters of the engine, comparing the state parameters with a criterion for slow acceleration or deceleration; if the acceleration is determined to be too slow, canceling the current acceleration fuel supply rule and increasing it by a certain percentage based on the current acceleration fuel supply rule; if the deceleration is determined to be too slow, canceling the current deceleration fuel supply rule and reducing it by a certain percentage based on the current fuel supply rule; inputting the improved acceleration or deceleration fuel supply rule into the simulation model for simulation calculation; obtaining the simulation calculation results after input, determining the acceleration or deceleration amount of the engine, judging whether the acceleration or deceleration amount of the engine reaches the target value, and if it does, adopting the acceleration or deceleration fuel supply rule as the new fuel supply rule for the engine.

[0007] Preferably, the method for setting the slow acceleration criterion is as follows: if the engine supplies fuel according to the acceleration fuel-air ratio, and the current N2dot is less than the specified value, and this state is satisfied for several consecutive control cycles, then the slow acceleration criterion is satisfied.

[0008] Preferably, the method for setting the slow deceleration criterion is as follows: the engine supplies fuel according to the deceleration air-fuel ratio, and the current N2dot is greater than the specified value. If this state is satisfied for several consecutive control cycles, then the slow deceleration criterion is satisfied.

[0009] Preferably, N2dot is obtained from the total engine inlet pressure P1 and the converted speed N2r of the high-pressure rotor, and N2dot increases or decreases proportionally under different total engine inlet pressures.

[0010] Preferably, if the engine acceleration or deceleration amount after simulation calculation does not reach the target value, the fuel supply law under the previous ratio is increased or decreased again according to the current fuel supply law, and the deceleration or deceleration fuel supply law is input into the simulation model for simulation calculation again to obtain the simulation calculation result and determine whether the target value has been reached. This process is repeated until the simulation calculation result reaches the target value.

[0011] As one specific implementation, a turbocharged engine acceleration / deceleration fuel supply system includes: an engine state acquisition module for acquiring engine acceleration / deceleration state parameters; a control logic determination module for setting deceleration or slow deceleration criteria and determining whether the engine is accelerating or decelerating too slowly; a simulation calculation module for establishing a simulation model and performing simulation calculations on the acceleration or deceleration fuel supply rules input into the simulation model; and a target value determination module for determining whether the engine's acceleration or deceleration amount reaches a target value. If it does, the acceleration or deceleration fuel supply rule is adopted as the engine's new fuel supply rule.

[0012] This application discloses a turbocharged engine acceleration and deceleration fuel supply method. When the engine is running, it is first controlled according to the normally designed acceleration and deceleration fuel supply pattern. By setting criteria for slow acceleration and slow deceleration, the method determines whether the engine's acceleration or deceleration is too slow. If either criterion is triggered, it indicates that the engine's acceleration or deceleration is too slow, and the current acceleration or deceleration fuel supply pattern is canceled. For engines with slow acceleration, a certain percentage is increased based on the current acceleration fuel supply pattern to improve the engine's acceleration rate; for engines with slow deceleration, a certain percentage is decreased based on the current deceleration fuel supply pattern to improve the engine's deceleration rate. Then, simulation calculations are used to ensure that the new acceleration or deceleration fuel supply pattern has good deceleration performance, thereby effectively solving the problem of slow engine acceleration and deceleration, ensuring a reasonable fuel-air ratio, and guaranteeing stable engine operation. Attached Figure Description

[0013] 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.

[0014] Figure 1 This is a schematic diagram of the overall process of this application. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0016] A method for fuel supply during acceleration and deceleration of a turbine engine, such as Figure 1 As shown, it includes the following steps:

[0017] Step S100: Establish a simulation calculation model, obtain the acceleration and deceleration state parameters of the engine, and compare the state parameters with the criteria for slow acceleration or deceleration.

[0018] Different simulation calculation models should be established for different engine models. When the improved acceleration or deceleration fuel supply law is input, the engine model corresponding to the fuel supply law should be determined first, and then the corresponding simulation calculation model should be called up for calculation, so as to establish a unified model for different engine models. Of course, each engine model can also store only the corresponding type of simulation calculation model for calculation.

[0019] Acceleration and deceleration parameters are acquired in real time during engine operation. When the engine is found to be accelerating or decelerating too slowly, the parameters are directly fed back to the engine control system, which then performs new acceleration or deceleration control on the engine.

[0020] In step S200, if the acceleration is determined to be too slow, the current acceleration fuel supply pattern is canceled and a certain percentage is increased based on the current acceleration fuel supply pattern; if the deceleration is determined to be too slow, the current deceleration fuel supply pattern is canceled and a certain percentage is decreased based on the current fuel supply pattern; the increase or decrease percentage varies depending on the engine model, and specific percentage values ​​are given based on practical experience.

[0021] The method for setting the acceleration / deceleration criterion is as follows:

[0022] If the engine supplies fuel according to the acceleration air-fuel ratio, and the current N2dot is less than the specified value, and this state is satisfied for several consecutive control cycles, then the slow acceleration criterion is met.

[0023] The threshold values ​​for N2dot due to excessively slow acceleration can be given in Table 1. N2dot is related to the total engine inlet pressure P1 and the converted high-pressure rotor speed N2r. N2dot refers to the change in the high-pressure physical speed per second, with units of r / min / s. For P1 = 100 kPa (ground conditions), N2dot can be taken as approximately 0.15 times the N2dot during normal acceleration of the engine on the ground test bench. For other P1-related N2dot values, they can be reduced proportionally according to the N2dot corresponding to P1 = 100 kPa.

[0024] Table 1 N2dot Threshold Values ​​for Slow Acceleration

[0025]

[0026] The method for setting the criterion for slow deceleration is as follows:

[0027] If the engine supplies fuel according to the deceleration air-fuel ratio, and the current N2dot is greater than the specified value, and this state is satisfied for several consecutive control cycles, then the deceleration is too slow criterion.

[0028] The threshold value for N2dot due to excessively slow deceleration can be given in Table 2. N2dot is related to the total inlet pressure P1 of the engine and the converted speed N2r of the high-pressure rotor. For P1 = 100 kPa (ground conditions), N2dot can be taken as approximately 0.15 times the N2dot during the normal deceleration process of the engine on the ground test bench. For other P1 values, the N2dot can be reduced proportionally according to the N2dot corresponding to P1 = 100 kPa.

[0029] Table 2 N2dot Threshold Values ​​for Excessive Deceleration

[0030]

[0031] Step S300: Input the improved acceleration or deceleration fuel supply law into the simulation model and perform simulation calculations;

[0032] Step S400: Obtain the simulation calculation results after input, determine the acceleration or deceleration of the engine, and determine whether the acceleration or deceleration of the engine reaches the target value. If it does, then adopt the acceleration or deceleration fuel supply rule as the new fuel supply rule of the engine.

[0033] If the engine acceleration or deceleration amount after simulation calculation does not reach the target value, the fuel supply law under the previous ratio will be increased or decreased again according to the current fuel supply law, and the deceleration or deceleration fuel supply law will be input into the simulation model for simulation calculation again. The simulation calculation result will be obtained to determine whether the target value has been reached. This process will be repeated until the simulation calculation result reaches the target value.

[0034] At the same time, critical thresholds can be set for acceleration or deceleration fuel supply patterns. When the calculated fuel supply amount required for acceleration or deceleration exceeds the critical threshold, the threshold will be used to ensure stable engine operation.

[0035] When the engine is running, it is first controlled according to the acceleration and deceleration fuel supply pattern designed under normal conditions. By setting criteria for slow acceleration and slow deceleration, it is determined whether the engine's acceleration or deceleration is too slow. If the slow acceleration or deceleration criterion is triggered, it indicates that the engine's acceleration or deceleration is too slow, and the current acceleration or deceleration fuel supply pattern is canceled. For engines with slow acceleration, a certain percentage is increased based on the current acceleration fuel supply pattern to increase the engine's acceleration rate; for engines with slow deceleration, a certain percentage is decreased based on the current deceleration fuel supply pattern to increase the engine's deceleration rate. Then, simulation calculations are used to ensure that the new acceleration or deceleration fuel supply pattern has good deceleration performance, thereby effectively solving the problem of slow engine acceleration and deceleration, ensuring that the fuel-air ratio of the engine is set reasonably, and ensuring the engine's stable operating state.

[0036] As one specific implementation, a turbocharged engine acceleration / deceleration fuel supply system includes: an engine state acquisition module for acquiring engine acceleration / deceleration state parameters; a control logic determination module for setting deceleration or slow deceleration criteria and determining whether the engine is accelerating or decelerating too slowly; a simulation calculation module for establishing a simulation model and performing simulation calculations on the acceleration or deceleration fuel supply rules input into the simulation model; and a target value determination module for determining whether the engine's acceleration or deceleration amount reaches a target value. If it does, the acceleration or deceleration fuel supply rule is adopted as the engine's new fuel supply rule.

[0037] By setting a deceleration or slow deceleration criterion, the engine's acceleration or deceleration rate can be adjusted in a timely manner when the engine accelerates or decelerates too slowly, ensuring that the engine can accelerate or decelerate more quickly while maintaining stable engine operation.

[0038] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for fuel supply during acceleration and deceleration of a turbine engine, characterized in that, include: Establish a simulation calculation model, obtain the acceleration and deceleration state parameters of the engine, and compare the state parameters with the criteria for slow acceleration or deceleration; If the acceleration is determined to be too slow, the current acceleration fuel supply pattern will be canceled, and a certain percentage will be increased based on the current acceleration fuel supply pattern. If the deceleration is determined to be too slow, the current deceleration fuel supply pattern will be canceled, and the fuel supply will be reduced by a certain percentage based on the current fuel supply pattern. The improved acceleration or deceleration fuel supply law is input into the simulation model for simulation calculation. After obtaining the simulation calculation results after input, determine the acceleration or deceleration of the engine, and judge whether the acceleration or deceleration of the engine reaches the target value. If it does, the acceleration or deceleration fuel supply law is adopted as the new fuel supply law of the engine. The method for setting the acceleration-to-slowness criterion is as follows: If the engine supplies fuel according to the acceleration air-fuel ratio, and the current N2dot is less than the specified value, and this state is satisfied for several consecutive control cycles, then the slow acceleration criterion is met. The method for setting the slow deceleration criterion is as follows: If the engine supplies fuel according to the deceleration air-fuel ratio, and the current N2dot is greater than the specified value, and this state is satisfied for several consecutive control cycles, then the deceleration is too slow criterion.

2. The turbocharger engine acceleration / deceleration fuel supply method as described in claim 1, characterized in that: The N2dot is obtained from the total engine inlet pressure P1 and the converted speed N2r of the high-pressure rotor. The N2dot increases or decreases proportionally under different total engine inlet pressures.

3. The turbocharger engine acceleration / deceleration fuel supply method as described in claim 1, characterized in that: If the engine acceleration or deceleration after simulation calculation does not reach the target value, the fuel supply pattern under the previous ratio will be increased or decreased again according to the current fuel supply pattern. The acceleration or deceleration fuel supply pattern will be input into the simulation model for simulation calculation again. The simulation calculation result will be obtained to determine whether the target value has been reached. This process will be repeated until the simulation calculation result reaches the target value.

4. A turbocharged engine acceleration / deceleration fuel supply system, employing the method described in any one of claims 1-3, characterized in that, include: Engine status acquisition module, used to acquire engine acceleration and deceleration status parameters; The control logic determination module is used to set the criteria for deceleration or slow deceleration and to determine whether the engine is accelerating or decelerating too slowly. The simulation calculation module is used to build a simulation model and perform simulation calculations on the acceleration or deceleration fuel supply law input into the simulation model. The target value judgment module is used to determine whether the engine's acceleration or deceleration has reached the target value. If it has, the acceleration or deceleration fuel supply pattern is adopted as the engine's new fuel supply pattern.

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