Combined numerical and experimental investigation of a 15-cm valveless pulsejet

The pulsejet, due to its simplicity, may be an ideal micro propulsion system. In this paper, modern computational and experimental tools are used to investigate the operation of a 15-cm overall length valveless pulsejet. Gas dynamics, acoustics and chemical kinetics are studied to gain understanding of various physical phenomena affecting pulsejet operation, scalability, and efficiency. Pressure, temperature, thrust, and frequency are measured as a function of valveless inlet and exit lengths and different geometries. At this length scale, it is necessary to run the pulsejets on hydrogen fuel. Numerical simulations are performed utilizing CFX to model the 3-D compressible vicious flow in the pulsejet using the integrated Westbrook-Dryer single step combustion model. The turbulent flow and reaction rate are modeled with the k-epsilon model and the Eddy Dissipation Model (EDM), respectively. Simulation results provide physical insight into the pulsejet cycle; comparisons with experimental data are discussed.