带肋回转变截面通道内换热特性的实验研究

用实验方法研究了某航空发动机涡轮叶片内部带肋变截面180°回转通道壁面的换热特性,分析了上下面带60°平行斜肋和带60°交叉肋两种分布形式对换热的影响。实验结果表明:通道的努赛尔数随着雷诺数的增加而增大。在低雷诺数下两者的通道平均换热效果是相近的;在高雷诺数下交叉肋通道平均换热效果好于平行斜肋通道。变截面通道的壁面温度分布没有严格的以肋间距为周期的变化规律;交叉肋通道壁面温度沿流体流向的梯度要比平行肋通道的小。

Experimental Investigation of Heat Transfer in a Turnover Variable Cross-section Channel with Ribs

An experiment is performed on a facility with 180° turnover variable cross-section channel with ribs which is built based on the inner structure of the real turbine blade of an aero-engine. Heat transfer characteristics for the upper and lower surfaces with 60° parallel or crossed ribs are investigated. The results show that Nu number for the channel increases with Re number. The two rib configurations give similar heat transfer characteristics at low Re number and the interleaving rib configuration shows better characteristics than the parallel rib one at high Re number. The distribution of wall temperature is not consistent with the periodic arrangement of the ribs. The stream wise wall temperature gradient for the crossed rib one is lower than that for the parallel rib one.