燃烧室对接狭缝设计参数对压强振荡的影响研究

Effect of internal joint design parameters on pressure oscillation in combustion chamber

为了获得分段式固体发动机药柱对接部位狭缝宽度对发动机压强振荡的影响规律,针对某典型分段式固体发动机建立了二维轴对称模型。采用大涡模拟(LES)方法,以"突扩比"为重要设计参数,完成了6种不同"突扩比"设计条件下的分段式发动机流场稳定性数值模拟,并分别对其压强-时间曲线进行了FFT分析。结果表明,随着"突扩比"的逐渐增大,燃烧室压强振荡频率基本不变,但压强振荡的幅值总体上呈现下降的趋势。所得分析结果已得到试验的初步验证。

Aiming at revealing the relation between the internal joint width and the pressure oscillation for SSRM （ Segmented Solid Rocket Motor）, a two-dimensional axisymmetric model was built. LES （Large Eddy Simulation） was carried out for six differ ent expansion ratio. Finally,pressure evolution and its FFT（ Fast Fourier Transform ） results were analyzed. Results indicate that the amplitude of pressure oscillation displays a decrease tendency as the expansion ratio increasing, but the frequency of pressure os cillation is unchanged. The result has gained validation through SSRM static test.