预爆管设置方式对主爆轰点火的影响  

Influence of pre-detonator installation scheme on the detonation ignition of pulse detonation engines

作　　者：王晓栋[1] 

机构地区：[1]中国空气动力研究与发展中心,四川绵阳621000

出　　处：《空气动力学学报》2009年第3期340-345,共6页Acta Aerodynamica Sinica

摘　　要：应用含组分守恒方程的Navier-Stokes方程,对H2+O2预混气体的二维爆轰进行了数值计算。在建立方法、及验证的基础上,对比研究了化学动力学模型、预爆轰管几何位置对爆震燃烧室流场及引爆性能的影响。在计算过程中,对方程中的对流项采用了空间为二阶精度的AUSMPW+格式,扩散项则采用了二阶中心差分离散。采用流体力学时间步内的当地积分法克服了非平衡源项的刚性问题,保持了LU-SSOR隐式算法的高效率。非定常计算采用了双时间方法。预爆轰管与主爆震室平行,采用两种设置方案:一种正向安装推力壁上,另一种在推力壁附近与其相对设置。研究结果表明,反射激波及过爆轰驱动在爆轰点火和传播中起重要的作用,与推力壁相对设置的预爆轰管更有利于爆震的引发。In the present paper, numerical computations using the Navier-Stokes equations are carried out to simulate two-dimensional gaseous detonations in H2 ＋O2 mixtures. In the computing to the flowfields in the combustor, the effects of the chemical kinetic model and the installation scheme of the pre-detonator on the detonation ignition and transmission are studied comparatively. During the simulations, the second order M. S. Liou＇s AUSMPW＋ scheme is used for the inviscid flux terms and a central difference is used for the diffusion terms. Furthermore, using the local integral of the nonequlibrium source terms within local fluid time step and the LU factorization technique, an implicit LU-SSOR hybrid arithmetic without computing the inversion of the iteration matrix is established, guaranteeing the high efficiency of the method in simulating nonequlibrium flowfields. Furthermore, for unsteady problems, the dual-time method is introduced. The pre-detonator paralleling with the main detonation tube is installed in two basic ways： one is installed at the close end of the main detonation tube; another is oppositely installed near to the close end of the main detona- tion tube. The results demonstrate that the reflected shock waves and overdriven detonation play the important role in detonation ignition and transmission. Comparatively simulating also indicates that the pre-detonator oppositely installed makes detonation ignition and transmission more easily than the normal one does.

关 键 词：脉冲爆震发动机 点火 爆轰传播 数值模拟 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]