不同密度比下旋转方通道内流场和换热的数值模拟

Numerical Simulation of Flow and Heat Transfer in Rotating Square Duct with Varied Density Ratio

在雷诺数为25000、旋转数为0．24、密度比为0．07—0．22的范围内，以数值计算的方法模拟了旋转方通道内三维流场及换热分布，与公开文献中的换热实验结果进行的对比表明，低雷诺数κ-ω模型的计算结果与实验值吻合得相对较好；重点研究了旋转状态下冷气密度比对通道内流场和换热的影响，分析了哥氏力和浮升力在通道中的交互作用机理，结果表明，哥氏力引发的截面二次流是造成旋转通道前后缘换热差异的主要因素，浮升力加剧了通道内主流型的偏移，同时，其在前缘表面诱发的流体分离改变了局部湍流强度和换热分布。

At 25000, 0.24, 0.07 to 0.22. of Reynolds number, rotation number and inlet coolant - to - wall density ratio respectively the numerical simulation of the three - dimensional turbulent flow and heat transfer were performed in rotating square duct. The heat transfer comparison between the prediction and the published experimental data showed that the prediction from the low Reynolds κ - ε model was fit better with the data. The effects of coolant - to - wall density ratios on flow field and heat transfer in internal cooling channels under rotation were primarily investigated and the interaction of Coriolis and buoyancy forces in the duet were analyzed. The results showed that the Coriolis - driven secondary flow was the major factor for the heat transfer differences of the leading and trailing edges. The deviation of main stream pattern in the duet was intensified by the buoyancy force, and the buoyancy - induced flow separation in the vicinity of the leading edge changed the local turbulence intensity and heat transfer distribution.