旋转作用对带肋回转内通道换热特性影响

为了深入了解旋转作用对回转内通道换热特征的影响,采用三维数值模拟方法研究旋转数、旋转半径对带肋内通道模型的流动换热影响。通道入口雷诺数为1.7×104、旋转数范围为0～0.09,出口1、出口2、出口3的质量流量分配比为1∶2∶1,旋转半径与水力直径之比的范围为0～69.6。结果表明:旋转作用力使径向出流通道的压力系数逐渐增大,径向入流通道的压力系数迅速减小;径向出流通道后缘面的努赛尔数(Nu)随旋转数增加而增大,径向入流通道后缘面的Nu随旋转数增加而减小,前缘面Nu随旋转数变化情况相反;前、后缘面Nu沿流向均随旋转半径与水力直径比的增加略有增大,旋转半径变化对壁面换热影响较小。

The Effects of Force on Heat Transfer for Rotating Internal Cooling Channels with Rib Turbulators

To better understand the effects of rotation on the internal channel heat transfer characteristics ,the flow and heat transfer condition in an internal channel with 90＆#176; ribs are investigated using three-dimensional nu-merical simulation method .The inlet Reynolds number is 1.7＆#215;104 and three outlets mass flow discharge ratio is 1∶2∶1 .The Rotating number and the hydraulic diameter divided by radius of gyration range from 0 to 0.09 and 0 to 69.6 ,respectively .The influence of Rotation number and Radius of gyration on heat transfer coefficient were achieved .Results show that the pressure coefficient increases along radial outflow and decreases along ra-dial inflow due to rotational force;in the trailing surface ,Nusselt number（Nu） in radial outflow passages in-creases and the Nu in radial inflow passage decreases with the augment of the rotation number ,the variation of Nu in the leading surface contrary to that of the trailing surface;the Nu along the flow direction in trailing and leading surface are slightly enhanced when gyration radius to hydraulic diameter ratio increase ,the surface heat transfer coefficient is affected on the variable radius of gyration.