楔形扰流柱通道流动与传热特性

针对处在高速旋转(哥氏力、离心力以及诱导产生的浮升力)状态下的涡轮转子叶片尾缘独特的几何结构(带扰流柱的楔形通道)和特殊的流动方式(径向进气侧向出流),采用实验的方法在实际工况参数范围内对其传热和流阻特性进行了详细研究:雷诺数和旋转数的变化范围为20 000~45 000、0~0155。实验结果表明:扰流柱的存在使得径向区域底部的滞止区域变大,但这也让中部传热有明显的提升;流阻和综合传热系数的比光滑参数随着雷诺数的增加而下降;旋转对顶部传热有增强作用,底部传热减弱;总地来说旋转使得通道的平均传热减弱,流阻增加,综合传热系数下降。 

Flow and heat transfer characteristics in roughened rotating wedge-shaped channel with pin-fins

The trailing edge of the turbine rotor blades featured lateral extraction and the fin-pins were subject to Coriolis, centrifugal force, and induced buoyancy. Experimental methods were used to study its heat transfer and flow resistance characteristics within the parameters of the actual working conditions: Reynolds number and rotation number ranging from 20 000 to 45 000 and 0 to 0155, respectively. The experimental results showed that the presence of the pin-fins made the bottom stagnation area larger, whereas it also significantly improved the heat transfer in the middle radius. The ratio of the flow resistance and the thermal performance decreased with the Reynolds number. However, the rotation enhanced the heat transfer at the top and weakened that at the bottom. In general, the rotation increased the flow resistance, while the average heat transfer and the thermal performance were deteriorated.