Research of Comprehensive Modeling of Two-Dimensional Vector Nozzle/Actuator Load/Turbofan Engine

Abstract

To investigate the effect of the dynamic deflection process of a two-dimensional vector nozzle on its actuator load and engine performance, a comprehensive modeling method of two-dimensional vector nozzle/actuator load/turbofan engine is proposed. Firstly, based on the two-dimensional vector nozzle spatial motion model, combined with force and moment analysis, the mechanical model of vector nozzle actuation system is established; The load spectrum of the actuating system under different working conditions and deflection angles is obtained by CFD numerical simulation results; Using AMESim, the hydraulic actuation system model of two-dimensional vector nozzle is established. Finally, a twodimensional vector nozzle/actuator/turbofan engine comprehensive model is established based on the component-level model of turbofan engine. The comprehensive model can accurately calculate the changes of main performance parameters such as engine rotor speed, thrust and pre-turbine temperature when the nozzle vector deflects. The simulation results show that the load on the nozzle actuator is positively correlated with the deflection angle, and the load change will lead to the fluctuation of the output displacement of the hydraulic actuation system. During vector deflection, due to the change of engine circulation capacity and thrust coefficient, the performance parameters such as engine low-pressure rotor speed and surge margin fluctuate greatly.

A hybrid dynamics modeling method for micro-turbine engine thrust vectoring

“…2) Test modeling, through the analysis of the engine test data, and study of its input parameters and output parameters in different environmental parameters by parameters identification methods, such as optimization smooth expansive least squares method, multi-objective genetic programming etc [7][8][9][10], to get the model of the engine, which does not require an understanding of engine's running principle and has a lower cost to obtain, is of great use in micro-turbine engines. Thrust vector modeling is usually done in the form of geometric modeling, which decomposes the thrust, but does not take into account the dynamics of the actuation mechanism and the thrust loss introduced by nozzle [11][12][13][14].…”