摘要
设置不同网格条件,使用尺度自适应模拟(SAS)方法对流动情况复杂的高亚临界雷诺数圆柱绕流进行了数值计算,重点从模型尺度分布、湍流结构捕捉能力及流场统计积分量等方面分析了SAS方法的网格敏感性及对大分离流动的解析能力。计算结果表明:SAS方法使用基于当地速度导数的冯卡门尺度作为调节尺度,具有良好的湍流谱生成能力,且有效避免了使用网格尺度时的近壁“灰区”缺陷;使用密网格时计算的冯卡门尺度局部分辨率更高,获得了与实验值更接近的壁面压力、流场速度、阻力系数等物理量;使用粗网格时捕捉到的小尺度湍流涡结构较少,表现出较大的耗散性,SAS方法高精度湍流求解仍需一定密度网格支持。
Under different grid densities,flow in a circular cylinder at high sub-critical Reynolds number is simulated using the Scale-Adaptive Simulation model(SAS).The grid sensitiveness characteristics of SAS method as well as the calculation accuracy to the massively separated flows are further investigated through the simulated scale distribution,the velocity shape,the reproducing effect of turbulence structure and the summary of the statistical flow data.From the assessment,the SAS formulation employing von-Karman scale appears positive turbulence-adjusting ability and the border intrusion issue in DES simulation is reliably remedied.The comparison data turns out that the SAS simulation of wall pressure,velocity sharp,drag coefficient and so on using fine grid is more comparable with experimental values and more accurate in local scale adjusting process.While the SAS result under coarse grid reproduces less turbulence-Eddy,which means more dissipative.In a word,the appropriate grid is significantly needed for an acceptable Scale-Adaptive Simulation.
作者
常玲玲
刘跃
Chang Lingling;Liu Yue(Engineering Research Center of Aerospace High-End Manufacturing-Universities of Shaanxi Province,Shaanxi Institute of Technology,Shaanxi Xi'an,710300,China)
出处
《机械设计与制造工程》
2024年第8期123-127,共5页
Machine Design and Manufacturing Engineering
基金
陕西省教育厅科技处项目(22JK-0273)
陕西国防工业职业技术学院校级重点项目(Gfy19-01,Gfy22-09)。
关键词
湍流模型
尺度自适应模拟
分离涡模拟
圆柱绕流
数值模拟
turbulence model
scale-adaptive simulation
detached-eddy simulation
cylinder flow
numerical simulation
