透平叶栅端区二次流具有复杂的涡系结构。Langston实验描述了两支马蹄涡和通道涡的演变和发展过程。基于Langston叶型构造出有效的前缘壁角，建立涡轮叶栅带有前缘壁角的端壁流动计算模型，分析前缘壁角对端壁流动与传热特性的影响，并评估其在非设计条件下的适应性。结果表明：在一定的非设计工况范围内，前缘壁角削弱了前缘马蹄涡和通道涡的强度，降低了流道内部的气动损失，增加了近端壁的流动损失。有效的前缘壁角使前缘附近端壁换热水平减弱，流道端壁换热整体减弱，端壁高换热区沿流向下移，尾缘附近换热有所增加。在一定的非设计工况范围内，前缘壁角都是有效的。

An effective leading edge fillet is designed for Langston linear cascade,with which the end-wall flow calculation model is established.The rnfluerce of leading edge fillet on the flow field and heat transfer performance is analyzed and the effectiveness of leading edge fillet at offdesign incidence conditions is identified.Results show that leading edge fillet reduces the strength of horseshoe and passage vortex within a specific range of incident angle.The passage-averaged total pressure loss at the cascade exit is decreased while the local loss value close to endwall is increased.Heat transfer coefficients near leading edge are reduced.Stanton number near trailing edge is increased.The area of high heat transfer coefficient is moved downstream.Leading edge fillet functions effectively within certain off-design incidence range,although its effectiveness decreases as incidence increases.

TK47

国家自然科学基金资助项目(51276116)