横流通道中肋角度对外表面气膜冷却影响研究

采用非结构化网格和Realizablek-ε紊流模型,求解三维N-S方程,对带肋横流通道中肋的角度不同情况下,外表面气膜冷却换热特性进行了数值模拟。具体分析了肋与横流流动方向成60°、90°、120°时对气膜冷却外表面换热系数的影响。结果表明:横流及肋的存在使通道流场变得非常复杂,肋角度的变化对气膜孔内及出口气体流动有较大影响;肋角度的变化还改变了外表面换热系数的分布,肋角度为120°时外表面换热系数最大,60°次之,90°最小。

Influence of the Angle of Ribs on Film Cooling Characteristics of the Outer Surface with Crossflow

Unstructured mesh and realizable k-ε model were used to resolve three-dimension N-S equation and to simulate the film-cooling and heat transfer characteristics of the outer surface of a channel with crossflow under various angles of rib turbulators.The effect of three kind of angles(60°,90°and 120°)between crossflow and ribs on the heat transfer characteristics of the outer surface with film cooling is studied.The results show that the flow filed becomes complicated because of the crossflow and ribs.The flow structure in the film-cooling hole and outside is controlled by the angle of ribs;it also changed the distribution of the outface heat transfer coefficient.The heat transfer coefficient appears to be the greatest when the channel has a crossflow-rib angle of 120°,followed by an angle of 60° and 90°.