Strategies for PDE performance optimization

Abstract

The Pulsed Detonation Engine (PDE) concept is systematically analyzed with respect to design variations and the potential performance is measured from Computational Fluid Dynamics (CFD) simulations. Single-pulse computations are performed first while some of the geometrical parameters are varied. These show that the presence of a nozzle can greatly affect the performance of the PDE by increasing thrust delivery during the ignition phase. It is further shown that it is not necessary to fill the entire tube with a fuel-air mixture and that significant gains in specific impulse can be obtained by appropriate fueling strategies. Multi-cycle computations are performed next, and the effect of cycling parameters is studied. We show that the cycling frequency can be significantly increased by selecting the pressure parameters and the extent of refueling. We also show that multi-cycle performance can be very different from the single-pulse estimates, and that it is not possible to optimize separately the ignition phase from the injection phase. Finally, the question of open-end initiation is examined and a comparison with 2D is performed.