发汗冷却湍流换热过程的数值模拟  

Numerical simulation for turbulent transpiration cooling processes

作　　者：余磊[1] 姜培学[1] 任泽霈[1] 

机构地区：[1]清华大学热能工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2003年第12期1668-1671,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家杰出青年科学研究基金(50025617)

摘　　要：为了验证湍流二方程模型在数值模拟发汗冷却过程的适用性,在PHEONICS3.3软件平台上采用两层k-ε湍流模型对无发汗冷却和有发汗冷却时的矩形槽道内湍流流动和换热进行了数值模拟。计算结果表明:发汗冷却使得边界层显著增厚,壁面摩擦阻力因数大为减小;随着冷却气体流量的增加,壁面温度和局部对流换热系数都大大下降。在注入率为1%左右时,发汗冷却段的壁面温度相对值降到了20%左右,局部对流换热系数相对值降到了50%以下。所得到的计算结果与已有关系式符合得很好:注入率在2%以内时误差小于10%。The turbulent flow and heat transfer characteristics in a rectangular channel with and without transpiration cooling were analyzed numerically to verify the turbulent two-equation model for flows with transpiration cooling. The two-layer k-ε model in PHOENICS 3.3 was used to calculate the turbulent velocity and temperature distributions for the main flow. The calculation results show that transpiration cooling greatly increases the boundary layer thickness and reduces the wall friction coefficient. The main flow velocity perpendicular to the wall is also increased. Both the wall temperature and the convection heat transfer coefficient decrease sharply with increasing cooling flow rate. For a blowing ratio of 1%, the wall temperature along the transpiration cooling wall was reduced by about 20% and the convection heat transfer coefficient and average wall friction coefficient were reduced by about 50%. The numerical results agree well with known correlations with errors of less than 10% when the blowing ratio was less than 2%.

关 键 词：发汗冷却 湍流 换热过程 数值模拟 传热学 对流换热 流动阻力 

分 类 号：TK12[动力工程及工程热物理—工程热物理]