自由液体射流冲击高速旋转圆盘的耦合换热

为了研究自由液体射流冲击均匀加热高速旋转圆盘的耦合换热特性，采用数值模拟方法对比分析了固体和流体材料参数对流动及换热的影响。结果表明：不同固体材料参数对应的努塞尔数分布规律相似，同一半径位置处的努塞尔数最大相对偏差不大于10%。与径向温度分布相比，轴向温度差受固体材料导热系数变化的影响更大，铜和泡沫砖的径向最大温差仅相差3倍，而与导热系数近似呈反比的最大轴向温差相差达3 471倍。圆盘表面液膜平均径向流速和换热性能随流体黏度的增加而下降。黏度较小的氨和水对应的二次峰值换热强度较一次峰值的增加量超过了15%，黏度较高油类的二次峰值换热强度仅为一次峰值的50%～60%。射流介质采用黏度较小的水和氨时，盘面温度几乎保持不变，最大温差比小于7.86×10^-4；黏度较大的油类作为射流介质时在驻点附近的温度变化剧烈，当R/d超过2.5后，温度分布仅有小幅的波动。

Conjugate heat transfer of free liquid jet impinging on high-speed rotating disk

To study the conjugate heat transfer characteristics of a free liquid jet impinging on a uniformly heated high-speed rotating disk, the effects of solid and fluid material parameters on the flow and heat transfer were analyzed by numerical simulation. The results showed that the local Nusselt number distribution corresponding to different solid material parameters was similar, and the maximum relative deviation of the Nusselt number at the same radius position was not more than 10%. Compared with the radial temperature distribution, the axial temperature difference was more affected by the change in the thermal conductivity of the solid material. The maximum radial temperature difference between copper and foam brick was only 3 times, while the difference between the maximum axial temperature difference approximately inverse to the thermal conductivity was 3471 times. The average radial velocity and heat transfer performance of liquid film on the disk surface decreased with the increase of fluid viscosity. The secondary peak heat transfer intensity corresponding to ammonia and water with less viscosity increased by more than 15% compared with the primary peak, and the secondary peak heat transfer intensity of lubricant oil with higher viscosity was only 50%—60% of the primary peak. When water and ammonia were used as the jet medium, the surface temperature of the disk remained almost constant, and the maximum temperature difference ratio was less than 7.86×10-4. When the lubricant oil was used as the jet medium, the temperature near the stagnation point changed drastically. In the region with R/d exceeding 2.5, the temperature distribution only fluctuated slightly.