Research on the Influence of Variable Geometry Power Turbine Speed Adjustable on the Overall Performance of Turboshaft Engine

Turboshaft engine has been widely used in aviation, land and other fields, and its operating range is expanding day by day. The performance of turboshaft engine with fixed geometry and fixed speed power turbine is greatly restricted. In this paper, T700 turboshaft engine is taken as the research object to explore the influence of variable power turbine geometry and adjustable speed on its overall performance. Referring to the design parameters of the engine, the 0D calculation model of turboshaft engine is built by using Matlab/Simulink platform. The influence of power turbine speed change on the overall performance is analysed, and the influence law of speed change on the overall fuel consumption is obtained, and the optimal variable speed strategy is determined. The characteristic diagram of the power turbine under different guide vane openings is obtained by using the NUMECA three-dimensional numerical simulation. After modeling, the overall performance series analysis is carried out, and the influence law of the different guide vane openings on the overall fuel consumption rate of the power turbine is obtained. Based on the relevant calculation results, the performance change of variable geometry power turbine is determined when the speed changes.