关键词: 超音速燃烧, 数值模拟, 燃烧效率, 有限速率模型, 雷诺应力模型

Abstract: In order to enhance the combustion efficiency of supersonic combustion chamber with a rearward facing step, this paper presents a new method which adds a transverse air injection after the hydrogen injection. A numerical simulation study of this method has been done using Reynolds stress model and finite-rate chemistry model with detailed chemical reaction mechanism of hydrogen-air combustion. The results show that this method may effectively enhance the mixing efficiency of hydrogen and air, and that the combustion efficiency is improved from 60% to 64% under the computational conditions. However, as the static pressure and Mach number of the transverse air injection increase, a separation of the supersonic air stream firstly arises at the corner of the step and then there will be a shock wave at the cross section of the step. After that the position of the shock wave gradually moves upstream. In addition, the total pressure loss increases.

Key words: supersonic combustion, numerical simulation, combustion efficiency, finite-rate model, Reynolds stress model