类壁角端壁造型设计方法

Design Method for Fillet-like End Walls

基于透平叶栅简化前缘模型的数值模拟结果,分析了原始模型端区的流动与传热特性,建立了一种新型类壁角端壁造型,对比评估了新型端壁模型、带前缘壁角模型与原始模型的流动与传热现象。结果表明:类壁角端壁造型的使用能够使端壁压力分布更加均匀;前缘滞止位置的低能流体在端壁压力的诱导下偏向主流,马蹄涡强度也随之减小;相比于带前缘壁角模型,新型端壁模型能够消除端壁与前缘壁角间的曲率间断线,疏导前缘两侧的堆积流体,抑制高强度角涡的产生,使壁面传热能力减弱。

Based on simulation results of the simplified leading-edge model for turbine blades, a new model was developed for the fillet-like end wall by analyzing the flow and heat transfer characteristics of the end wall in the original model, and subsequently the flow and heat transfer behaviors were comparatively studied among the new end wall model, the end wall model with leading-edge fillet and the original model. Results show that the use of fillet-like end wall would make the static pressure distribution more uniform;the low energy fluid in the leading edge stagnation zone would flow toward the mainstream under the guidance of end wall pressure, and the strength of the horseshoe vortex would drop accordingly. Compared with the model with leading-edge fillet, the use of the new end wall model could eliminate the discontinuous line of the curvature between the end wall and the fillet, lead the accumulative low energy fluid out of the corner region, inhibit the generation of high strength corner vortex and decrease the heat transfer on the leading edge.