Numerical study of hollow rotating detonation engine with different fuel injection area ratios

Three-dimensional numerical simulations are performed to study rotating detonation engines (RDEs) with a hollow combustor. The computations are based on the reactive Euler equations. The reactions of stoichiometric hydrogen-air mixtures are calculated by the one-step Arrhenius chemistry model. The hollow RDE combustors with different fuel injection area ratios on the head end wall are considered. The fuel injection area ratios range from 55.6% to 88.9%. The number of rotating detonation waves in the flow field of the hollow combustor is found to be related to the fuel injection area ratio. In the hollow combustors with fixed dimensions, the number of detonation waves increases when the fuel injection area ratio is higher. In addition, a comparative analysis of the hollow RDE model and the conventional annular RDE model is performed with respect to the flow field and fuel injection conditions. The propulsive performance of the hollow RDE with different fuel injection area ratios is also evaluated and compared with experimental data and other simulation results. It is demonstrated from several aspects that the removal of the inner wall does not sacrifice the propulsive performance of the RDE. (C) 2016 by The Combustion Institute. Published by Elsevier Inc.