多孔气膜冷却纵向耦合涡的数值模拟

应用Realizable k-e 紊流模型并结合SIMPLEC算法，近壁区流动的处理采用加强壁面函数法，对多孔气膜冷却进行数值模拟，将数值解与实验值进行比较，对纵向耦合涡的发展与冷却死区范围变化的关系进行探讨。结果表明，数值计算可较真实地模拟平板多孔气膜冷却气膜孔间气膜冷却效率的分布规律。冷却气流对底面形成气膜冷却的效果是由于纵向耦合涡覆盖在底面之上，阻隔主流与底面直接接触；气膜孔后高涡量、低涡心位置的纵向耦合涡的形成有助于提高其覆盖区域的气膜冷却效率；底面气膜冷却效率的分布规律与纵向耦合涡在底面上的覆盖范围一致，多孔气膜冷却气膜孔后纵向耦合涡的汇合位置直接影响孔间冷却死区的范围。

Numerical Simulation in Lengthways Coupled-vortex of Multiple Holes

Using the Realizable k-ε turbulence model, SIMPLEC algorithm and the enhanced wall treatment, numerical simulation was performed to investigate multiple holes film-cooling. The simulation result was compared with the experiment data, and relationship between lengthways coupled-vortex and cooling deterioration area was discussed. The results show that numerical simulation can get the right distributing rules of film cooling efficiency between jet holes. The cooling flow has the cooling effect on the flat for the flat is covered with lengthways coupled-vortex, which obstructs the main flow and the flat. The lengthways coupled-vortex behind the film cooling holes which is of high vorticity and low vortex heart is helpful to improve the film cooling efficiency on the area covered. The distributing area of the film cooling efficiency is the same as covering area of lengthways coupled- vortex on the flat, and the position where lengthways coupled- vortex behind the film cooling holes converges directly effects the cooling deterioration area between the film cooling holes.