【摘要】 采用三维非定常气热耦合模拟的数值方法,对具有冷却结构的单级涡轮进行非定常流动和冷却性能进行研究,通过对非定常流场和固体温度场的分析来探讨冷气对叶片排内流场和固体温度场的影响,指出在非定常状态下,不同的动、静叶相对位置对应不同的气膜出流情况。上游周期性不稳定尾流会造成下游动叶片主流掺入气膜保护层,会造成气膜冷却效率降低。尾迹对叶片前缘的撞击引起瞬间的冲角增大,叶片气动负荷以及温度分布存在一定程度的波动,吸力面前缘受到的干扰更为明显。更多还原

【Abstract】 By using a numerical method for simulating three-dimensional unsteady air-heat coupling,studied were the unsteady flow and cooling performance of a single-stage turbine with cooling structures.Through an analysis of the unsteady flow field in the blade cascade and the solid temperature field,the influence of cold air on them was explored.It is noted that under the unsteady state,various relative positions of the rotor and stator blades can produce accordingly different air-film outflow conditions.The upstream periodic unsteady wake flow may lead to a mixing of the main stream in the rotor blades at the downstream with the air-film protection layer and cause a decrease in air-film cooling efficiency.The impingement of the wake flow on the leading edge of the blades will lead to a sudden increase in the attack angle,the aerodynamic load and temperature distribution on the blades will produce a fluctuation to a certain degree and the disturbance received by the leading edge of the suction surface will become more evident.更多还原