旋转状态下矩形微小通道流动与换热试验研究

Experimental Study on Flow and Heat Transfer of Rectangular Microchannels on Rotating State

为了研究微小通道结构在航空发动机涡轮叶片中应用的前景和可行性，以空气为冷却介质，在Re一1000～3000、转速为0～500r／min、Ro=0～3．5×10^-3条件下，对水力直径为1mm的旋转微小通道组的流动和换热特性进行试验研究。结果表明．微小通道流阻系数呈现粗糙壁通道特征，通道临界Re≈2350，流阻系数以及临界Re随转速增加未见明显改变。在静止状态下，通道组综合换热系数随Re增大而增大，换热系数分布沿流动方向逐渐减小；在旋转状态下，通道组平均综合换热系数略有增大，旋转对换热特性的影响随着流动的发展而增大。

In order to find a way to use the microchannels into aeroengine turbine blades, the experimental investigation was conducted to explore the flow and heat transfer behaviors in the rectangular microehannels, which hydraulic diameter is lmm, taken air as coolant, in which the range of the Reynolds number is from 1000 to 3000. The rotating velocity varies from 0 to 500 r/min. The rotating numbers are changing from 0 to 3.5×10^-3. The results showed that the flow resistance coefficient of the mierochannels renders the rough wall characteristics. The critical Reynolds number is about 2350. With the increasing of the rotating velocity, the flow resistance coefficient and the critical Reynolds number shows no significant change. In the stationary state, the integrated heat transfer coefficient is increasing with the Reynolds number, but its distribution go down along the flow direction. In the rotating state, the integrated heat transfer coefficient increases slightly. The influence of rotating on the heat transfer characteristics increases with the developing of the flow.