受浮力作用的湍流扩散火焰的数值模拟

Simulation of Turbulent Non-Premixed Flames Influenced by Buoyancy

应用浮力修正的k ε模型和EDC湍流燃烧模型对旋流燃烧室内具有较低燃料/空气初始动量的甲烷湍流扩散火焰进行了数值模拟,得到了两组工况下的气体时均速度场、温度场、组分浓度场和湍流脉动速度均方根值分布等,并与实验数据进行了比较,二者基本相符.同时,还将计算结果与标准k ε模型的模拟结果进行了对比,揭示了浮力对具有较低初始动量的湍流扩散火焰的影响.

The buoyancy-modified k-Ε model and the eddy-dissipation-concept (EDC) turbulent combustion model are employed to numerically simulate the methane turbulent non-premixed flames with low fuel/air initial momentum in a swirl combustor. Two cases of the calculated results of time-averaged gas velocities, temperature and species concentrations, root-mean-square of fluctuating gas velocity and other quantities are obtained. They are compared with the measured test data. General agreement between them is achieved. At the same time, the calculated results are also compared with those obtained by the standard k-Ε model. With these comparisons, the influence of buoyancy on the turbulent non-premixed flame with low initial momentum is delineated.