热斑在1-1/2级涡轮内的非定常迁移数值模拟

Numerical Simulation of Unsteady Hot Streak Migration in a 1-1/2 Stage Turbine

对典型的1-1/2级高压涡轮叶栅,通过求解二维非定常N-S方程研究了燃烧室出口热斑对涡轮一级动叶和二级导叶流场和温度场的非定常影响。计算表明热斑的存在对涡轮级型面时均压力的影响微小,但是会显著地增大一级动叶和二级导叶型面压力随时间波动的幅度。计算印证了热斑会导致涡轮一级动叶压力面严重过热的结论,并显示在二级导叶上会出现与一级动叶类似的压力面过热现象。

Two-dimensional unsteady Navier-Stokes simulations were applied to the cascades of the typical first-stage turbine blade and second-stage guide vane to study the effects of combustor hot streaks on the flow and temperature fields. The predicted results show that the existence of hot streak has small impacts on the time-averaged static pressure around the turbine blade airfoils, but would increase the unsteadiness of static pressure around the first-stage rotor blades and second-stage guide vanes. The simulations verify the facts of the blade pressure surface overheating induced by the hot streaks, and there is similar effect on the increase of the guide vane pressure surface temperature.