湍流燃烧模型对氢燃料超燃室流场模拟的影响

采用化学平衡的假定概率密度函数(PDF)模型和火焰面模型计算了德国宇航研究中心的超燃室反应流,计算结果与有限速率反应模型的和实验的结果进行了对比.使用有限体积法离散Favre平均的N-S方程,湍流模型采用k-ε模型.研究表明:(1)有限速率反应模型在喷氢孔近场,化学平衡的假定PDF模型在喷氢孔远场不能准确捕捉流场的细致结构,而火焰面模型对全流场预测较好,后两种模型的计算时间较有限速率反应模型节省约38%;(2)超燃室内湍流和燃烧相互作用不可忽略,从预测精度和计算效率来看,火焰面模型有较好的工程应用前景. 

Effect of turbulent combustion model on simulation of hydrogen supersonic combustion

The equilibrium chemistry model using assumed probability density function(PDF) and the flamelet model were adopted to numerically simulate the reactive flow filed of the supersonic combustor of The Geman Aerospace Center.The calculated results were compared with those of the finite-rate chemistry model and the experiments.Finite volume method was used to discretize Favre-averaged Navier-Stokes equations,and κ-ε turbulence model was employed.The results show:(1)the finite-rate chemistry model and the equilibrium chemistry model using assumed PDFcannot capture fine structures of near-field and far-field from the hydrogen injector,respectively,while the flamelet model can predict the flow field well,and computation time of the latter two models is saved about 38% over that of the finite-rate chemistry model;(2) the interaction between turbulence and chemistry in the reactive flow filed of the supersonic combustor should not be ignored,and the flamelet model may have a bright prospect in engineering practices in terms of efficiency and accuracy.