ON THE ACCELERATION CONTROL OF DOUBLE SPOOL TURBOJET ENGINE OF UNKNOWN COMPRESSOR MAP

In this paper a method for theoretical prediction of double spool turbojet engine acceleration characteristics is presented. The acceleration characteristics of the engine are investigated on the basis of its compressors' maps with different operational limitations. Therefore, a special effort is paid for the construction of the studied engine compressors' maps. Different acceleration paths are selected on the compressor map and the required acceleration characteristics are calculated for each path. A non-linear model ._of the studied engine ;s developed and linearized about five different equilibrium points along the equilibrium run line. The linearized engine model is used to obtain the transient behavior of the engine. A special attention is paid to the effect of using the hydraulic retarder for acceleration control. The acceleration characteristics of the engine, equipped with hydraulic retarder, are determined by using a simulation program. The simulation program is used to predict the effect of the hydraulic retarder constructional parameters on the engine acceleration characteristics. These constructional parameters could be tuned to reproduce the required acceleration characteristics of the engine.