气动参数对后台阶三维缝隙换热影响的研究

针对涡轮叶片尾缘冷却结构特点,建立了后台阶三维缝隙结构气膜冷却特性试验台,测量了缝隙中心和肋中心下游换热系数的局部分布,研究了不同雷诺数Re(5000~15000)与吹风比Br(0.5~2.0)对换热系数的影响规律,试验结果表明:(1)出口的换热系数总体呈下降趋势,但在肋后中心线略有起伏;(2)随着Re的增大,换热系数增大,随着Br的增大,换热系数减小;(3)在靠近出口位置,由于热边界层与三维掺混特性流场的影响,使得换热变得复杂。

Effect of aerodynamics of back-step three dimensional slots on heat transfer coefficients

Heat transfer coefficients of back-step three dimensional slots injection,which modeling the trailing edge cooling of turbine blade,was measured at the slot center line and rib center line.The effects of aerodynamics of slot on heat coefficients have been studied.The range of Re from 5000 to 15000 and the range of Br changed from 0.5 to 2.0.The experimental results show that the profile of heat transfer coefficients is different at the slot center line and rib center line.Br has evident influence on the film cooling effectiveness.The sizes of three dimensional mixing flow region is increase with the increase of Re and Br.