一种求解化学非平衡流动的新型解耦算法

A NOVEL UNCOUPLED ALGORITHM FOR SOLVING CHEMICAL NONEQUILIBRIUM FLOWS

在一种新型化学非平衡流解耦算法框架下,将WENO5M格式用于化学非平衡流动的流场计算.为了验证所发展算法的准确性,对多个典型算例进行了计算.首先计算了Oran的反射激波诱导爆轰实验,并考虑了不同化学反应机理和网格收敛性的影响,得到的计算结果与实验和其他文献给出的计算结果符合很好,并且由于采用了一种最近提出的氢氧燃烧机理,模拟得到的实验中各个事件发生的相对时间相比于与以前的计算结果与实验符合得更好.然后计算了二维H2/O2/Ar爆轰,计算得到的胞格结构与实验和其他模拟结果符合较好,并得到了详细的爆轰发展历程.由于这种新型解耦算法的特点,仅需对现有的基于量热完全气体的可压缩流动计算程序做很小的修改,即能改造成化学反应流动计算程序,从而进一步体现了这种解耦算法的优势.

The WENO5 M scheme is modified to simulate the chemical reacting flow based on a novel uncoupled method for chemical nonequilibrium flow. For validating the new implementation, several benchmarks have been tested. The Oran's shock induced detonation experiment has been simulated first. The influences of different chemical reaction mechanisms and grid convergence have been considered and the results compare well with those from experiments. The second test case is the 2d H2/O2/Ar detonation, and the simulated cell structure compares well with the experiment results and other simulated results. Through these validations, we can conclude that the new implementation of WENO5 M scheme for the simulation of chemical reacting flow based on the novel decoupled method is satisfied. Because the extension of original WENO5 M scheme to calculate the chemical reacting flow based on the novel algorithm is straightforward and only minor modifications are needed, the advantages of this uncoupled algorithm is obvious.