湍流模型对数值模拟合成气射流火焰的影响

摘要

This paper numerically studied the nonpremixed jet flames of CO/H2/N2 fuel(4∶3∶3 by vol-ume)obtained experimentally by Sandia National Laboratories with different RANS models,whose influence on the simulation was analyzed based on the experimental data. Simulation results illustrate that different RANS models lead to completely different results,only 4 of which agree well with the experimental data. For Standardk-ε model,the change ofCε1 from 1.44 to 1.60 improves the numerical result observably,while the same change does not com-pletely applicable to Reynolds stress model. At the same time,despite its larger amount of calculation than two-equation models,Reynolds stress model does not obtain more accurate result. In conclusion,Standardk-ωmodel can simulate jet flame most accurately with moderate calculation.%采用不同的雷诺平均湍流模型数值模拟美国圣地亚国家实验室的合成气(CO、H2、N2按体积比4∶3∶3混合而成)非预混射流火焰．以实验数据为基础，分析讨论不同湍流模型对数值模拟该射流火焰的影响．结果显示，不同的湍流模型对数值模拟结果的影响非常大，其中只有4种模型能够比较精确地模拟出该火焰．对于Standard k-ε模型，将模型常数Cε1的值由1.44改为1.60可以显著提升其计算精度，但是同样的改进对于雷诺应力模型并不完全适用．同时，虽然雷诺应力模型计算量比双方程模型大，但并没有得到更好的计算结果．综合考虑计算结果与计算量，以Standard k-ω模型的模拟效果最好．