湍流模型对过冷沸腾计算影响分析

摘要

采用ANSYS FLUENT14.5分析湍流模型对过冷沸腾的影响，建立多套网格，每套网格采用不同的湍流模型、壁面函数及两相湍流处理方法，将计算结果与基准实验数据进行对比，分析网格、湍流模型、壁面函数及两相湍流处理方法对计算精度的影响。通过分析发现：k‐ε模型的计算精度高于k‐ω模型的；Dispersed 方法和 Per Phase方法的计算精度相对于 Mixture的无明显提升；增强壁面函数对Y ＋≈1的网格无法获得满意的计算结果。%The ANSYS FLUENT14.5 was employed to simulate the two‐phase forced convection subcooled boiling in a vertical heated pipe .Different turbulence models ,wall functions and two‐phase turbulence treatments were utilized to each of four sets of grids .Results were compared with experiment data to analyze the effects of grids , turbulence model ,wall functions and two‐phase turbulence treatments .The results of k‐εmodel show better agreement with experiment data than those of k‐ωmodel .Dis‐persed and Per Phase treatments for two‐phase turbulence parameters perform no better than Mixture treatment .The enhanced wall function can’t achieve satisfactory results for the grid with near wall function Y + ≈1 .