Dynamic simulation of a wave-rotor-topped turboshaft engine

The dynamic behavior of a wave-rotor-topped turboshaft engine is examined u sing a numerical simulation. The simulation utilizes an explicit, one-dimen sional, multipassage, computational fluid dynamics- (CFD-) based wave-rotor code in combination with an implicit, one-dimensional, component-level dyn amic engine simulation code. Transient responses to rapid fuel flow rate ch anges and compressor inlet pressure! changes are simulated and compared wit h those of a similarly sized, untopped, turboshaft engine. Results indicate that the wave-rotor-topped engine responds in a stable and rapid manner. F urthermore, during certain transient operations, the wave rotor actually te nds to enhance engine stability. In particular, there is no tendency toward surge in the compressor of the wave-rotor-topped engine during rapid accel eration. In fact, the compressor actually moves slightly away from the surg e line during this transient. This behavior is precisely the opposite to th at of an untopped engine. The simulation is described. Issues associated wi th integrating CFD and component-level codes are discussed. Results from se veral transient simulations are presented and discussed.