Wall effect on the flow structures of three-dimensional rotating detonation wave

摘要

The wall effect on the flow structures of the three-dimensional rotating detonation wave in an annular chamber is investigated by utilizing premixed hydrogen/air at a stoichiometric ratio as the reactant and a 7-species-8-reaction finite-rate chemical reaction model for evaluating the chemical source term. Three cases are constructed with different flow solvers, i.e., Euler, Navier-Stokes and filtered Navier-Stokes with Improved Delayed Detached-Eddy Simulation to identify the wall effects. Both slip and non-slip wall boundary conditions are considered to quantify the viscous effect near the wall. It is found that the flow structures of the rotating detonation wave change notably when the effect of the viscous wall is taken into consideration, resulting in the extension of the deflagration zone to the upstream along the wall, the severe deformation of the detonation front at the unbounded side, and the formation of the reactant deficit. The mechanism of such alteration in the flow structures is analyzed, and the formation procedure of the reactant deficit zone is proposed. The comparison of specific impulse shows that our simulation is about 10% lower than the ideal two-dimensional rotating detonation engine model, and the practical experiment model is about 5.8% lower than our simulation. The wall effect, the three-dimensional effect and the turbulent mixing would lead to the performance losses. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.