基于飞参数据的双轴涡轮发动机不稳定工作判读方法

Instability Detecting Method of a Twin-spool Gas Turbine Engine based on Flight Data

为了通过飞参数据研判发动机工作情况,对双轴涡轮发动机工作特性进行分析,并提出一种基于飞参数据的双轴涡轮发动机不稳定工作的判读方法。在双轴涡轮发动机正常工作时,高、低压转子换算转速差和低压转子换算转速之间存在确定的对应关系,通过多架次飞参数据分析得以验证。在发动机气动失稳后这种对应关系会改变,可以通过分析换算转速差和换算转速之间的关系来研究发动机不稳定工作状态。将该判读方法应用于某次空中停车故障分析,结果表明:该方法简单易行,使用数据为常用飞参数据,计算工作量小,可以很好地描述发动机不稳定工作的发展历程,与直接判读数据相比,可提前约20s发现发动机工作偏离,较为准确地确定诱发原因,并可应用于发动机故障分析及预测。

In order to detect the working condition of the engine through the flight data,the analysis of the working characteristics of the twin-spool gas turbine engine was carried out,and a method for detecting the instability of the twin-spool gas turbine engine was pro⁃posed based on the flight data.There was a definite corresponding relationship between the non-dimensional rotational speed difference of high-pressure and low-pressure rotor and the non-dimensional rotational speed of low-pressure rotor when the twin-spool gas turbine en⁃gine worked normally.It was also verified through the analysis of multiple flight data that this corresponding relationship would change after the aerodynamic instability of the engine.The instability of the engine could be studied by analyzing the relationship between the non-di⁃mensional rotational speed difference and the non-dimensional rotational speed.The detecting method was applied in analyzing an engine shut-down in flight.The results show that this method is simple and easy,the data used are common flight data,and the calculation work⁃load is small.It can well describe the development process of engine instability.Compared with the direct detect data,the method can find the moment of departing from steady state 20 s earlier,and the cause can be determined more accurately,which can be applied to engine fault analysis and prediction.