基于自适应网格的钝头体激波诱导燃烧现象数值模拟研究

钝头体激波诱导燃烧是爆震研究的一个基本问题.针对化学恰当量比的H2/Air预混气体在Ma=4.79和Ma=6.46时的激波诱导燃烧现象开展数值研究,采用基于有限体积法的块结构自适应网格加密程序AMROC,对带化学反应源项的轴对称Euler方程解耦求解,考察了数值模拟中不同形式的MUSCL重构格式、限制器类型以及化学反应...

Numerical Study on Shock-Induced Combustion of a Blunt Projectile via an Adaptive Mesh Program

Shock-induced combustion of a blunt projectile is a basic problem in detonation research. Numer-ical simulations were conducted to study the shock-induced combustion phenomenon of a stoi-chiometric H2/Air mixture at the flow Mach numbers of 4.79 and 6.46. The block-structured adaptive mesh refinement program AMROC based on the finite volume method was adopted to solve the axisymmetric Euler equations with chemical reaction source terms, and the influence of some important factors such as the form of the MUSCL reconstruction, the slope limiter types, and the chemical reaction mechanisms were investigated. The results show that, based on the mesh adaption flag parameters, the program can realize adaptive mesh refinement efficiently. The comparisons with experimental results show that the accuracy of the unsteady shock-induced combustion simulation depends not only on the chemical reaction mechanism, but also on the form of the limiter. Adopting two different forms of the MUSCL reconstruction format acquires almost the same oscillating frequencies, which is 1.17% and 0.97% different from the result obtained in the experiment, respectively. Numerical study is conducted for comparing the classic Jachimowski mechanism with several newly developed pressure-dependent hydrogen/oxygen reaction mecha-nisms. It is shown that, in the unsteady shock-induced combustion case at Ma=4.79, the classic Jachimowski mechanism is still the most suitable mechanism to obtain the closest oscillating fre-quency to the experimental result. While in the steady shock-induced combustion case at Ma=6.46, all of the given mechanisms can give results that are in good agreements with the experiment.