分别采用标量联合的概率密度函数方法、稳态火焰面模型、Euler非稳态火焰面模型和基于有限体积/Monte Carlo混合算法的完备PDF模型对钝体驻定的Sydney湍流扩散火焰HM1进行数值模拟,以比较不同燃烧模型的性能,并比较标量联合的概率密度函数方法和Euler非稳态火焰面模型对氮氧化物排放预测的差异.计算结果和实验数据的比较表明,采用概率密度函数方法计算化学反应可以得到更好的结果但计算量较大,而用火焰面模型求解计算量较小,在接近完全燃烧的情形下,其计算结果比较合理.
A joint-scalar probability density function (PDF) method, a steady laminar flamelet model, a Eulerian unsteady laminar flamelet model and a hybrid RANS and PDF method are employed in calculating a bluff-body stabilized turbulent non-premixed Sydney flame HM1. Nitrogen oxides emission is numerically simulated with the joint-scalar PDF method and the Eulerian unsteady laminar flamelet model in order to investigate influence of combustion models on the formation of nitrogen oxides. Comparisons between numerical results and experimental data show that chemical reactions by PDF are best while the computational cost is expensive. The laminar flamelet model results shows lower computational cost and are reasonable in complete combustion.