Computational and experimental investigations of performance are reported for a Pulsed Detonation Engine (PDE) under cyclic operation using hydrogen-air mixtures. Simulations are performed for two geometry configurations to study how internal geometry influences performance of a PDE. The computational method simulates all the processes of the PDE cycle (fill, Deflagration to Detonation Initiation (DDT), propagation, blowdown and purge). Experiments are performed to validate simulation of the PDE cycle processes. Experimental measurements include DDT and blowdown visualizations, and dynamic pressure measurements. The results yield important insights into performance estimations of a PDE tube operating in a continuous cycle. Comparison of experimental and computational flow and scalar field visualizations show good agreement in cycle process time scales. Overall, there is good agreement between the numerical predictions and available experimental data on thrust generated by an ideal tube PDE. The predicted decrease of ～30% in the fuel-specific impulse (Ispf) for the benchmark tube when compared to the Ispf of an ideal tube is attributed to nonuniformities in the mixture composition, pressure drop resulting from internal geometry (DDT obstacles and a fuel-air mixing element), and backflows in the valveless benchmark tube due to a compression wave propagating into the upstream geometry. The effect of DDT-promoting obstacles on the fuel-specific impulse (Ispf) is estimated to be 16% for the H2-air benchmark tube with ten, 0.43 blockage ratio obstacles.
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