选择发动机最佳循环参数的一体化方法研究

 航空发动机是飞机的动力装置,它的性能、重量、尺寸都对飞机性能有显著影响。本文从系统工程的观点出发,综合考虑飞机、发动机性能的相互影响和匹配,提出了以最好地满足飞机飞行任务为目标,选择发动机最佳循环参数和调节计划的一体化方法。 本文的应用实例是歼击机动力改型时优选加力发动机的最佳设计方案。计算结果表明:飞机飞行任务不同、改型要求不同、约束条件不同,发动机最佳方案的类型、循环参数和调节计划也完全不同。因此,一体化选择方法具有重要实际意义。

INVESTIGATION ON INTEGRATED SELECTION OF OPTIMUM ENGINE CYCLE PARAMETERS

An aero-engine can be regarded as a subsystem of the aircraft system. It is obvious that engine performances, weight and dimensions have a strong effect on the aircraft flight performances. For a given flight mission, the optimal engine scheme must be able to meet the flight requirements with the greatest possibility. From the viewpoint of system engineering, a method for integrated selection of the optimal engine cycle parameters and the control scheme is proposed, which takes the matching and interaction between the engine and the aircraft. A rapid method for predicting turbojet or turbofan engine off-design performances was adopted and an empirical formula estimating the engine weight was developed.An optimization of an augmented engine scheme meeting the requirements of a modification has been accomplished as an example. The results show that the optimum cycle parameters and the control scheme are quite different if the mission, the requirements of modification or the technical constraints are varied. Therefore, the integrated selection of engine cycle parameters is of great importance.