The Research On Starting Process Modeling Of A Turboshaft Engine

The starting phase of a turboshaft engine is a very complex pneumatic and thermodynamic process, which involves the collaboration of the starter, the supply fuel system and all components of the engine. The reliability and lasting time of the starting process have crucial significance on engine applications. A valid starting model can efficiently guide the research on the starting process of a turboshaft engine. The key of modeling an aeroengine with component method is the valid component characteristics, but it is difficult to gain exact component characteristics of a turboshaft engine in low rotate speed range by experiments. In this paper, four methods are attempted to obtain the characteristics of compressor and turbine in low speed range, they are beta-line extrapolation, exponent adjustment extrapolation, Back-Propagation artificial network extrapolation and approximate algorithm. In term of the component characteristics in low rotating speed range, considering the effect of combustion efficiency and thermal inertia, nonlinear equations were established to describe the starting process, then software was programmed. Consequently starting model of a turboshaft engine was developed. Finally, based on the starting model, several issues were studied, which included various factors that affect the starting characteristics, choosing an appropriate starter and finding a right supply fuel scheme. Then the result is feasible to requirement for starting process simulation.