气相爆轰波传播特性的数值模拟及实验对照

Numerical simulation of gaseous detonation waves propagation and comparison with experimental results

本文应用基元反应模型和频散可控耗散格式(DCD)对氢氧爆轰波进行了二维数值模拟。氢氧混合物的化学反应模型考虑了8种组分20个反应方程式。在处理化学反应引起的刚性问题时采用了时间算子分裂的方法。本文首先对爆轰波数值结果和实验结果进行了对照验证,然后对爆轰波在楔面反射由马赫反射向规则反射转变的过程进行了数值分析,得到了反射转变临界角,并和实验结果及理论分析进行了比较,结果是令人满意的;本文还对爆轰波的多波结构进行了初步的数值分析。

In this paper, the chemically reacting flow-field induced by detonation waves propagation is simulated with CFD methods. The dispersion-controlled dissipative scheme (DCD) is adopted to solve two-dimensional Euler equations implemented with detailed chemical reaction kinetics of hydrogen-oxygen-argon mixture. The fractional step method is applied to treat the stiff problem. For validation and verification, computational results are compared with experimental schlieren and nice agreement is obtained. The triple-point trajectories and the critical wedge angle αcr are measured experimentally, analytically and numerically. From numerical results it is observed that the critical wedge angle αcr for the transition from Mach reflection to regular reflection is very close to the experimental data. The numerical results also show that the angle (χ) of triple-point trajectory mainly depends on wedge angle (α) and is not sensitive to variation of the initial pressure P0. In addition, the detailed cellular structures are also simulated to demonstrate the evolution of multi-wave front structure of a detonation wave and the mechanism of the formation of triple-point when a detonation front reflects over a wedge.