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采用数值模拟方法研究了旋转工况下球窝/球凸结构对通道传热特性和阻力特性的影响,利用SSTk-ω湍流模型求解了黏性Navier-Stokes方程,其中矩形通道的一侧布置球凸,另一侧布置球窝,球窝/球凸的结构分为圆形、竖椭圆和横椭圆.研究结果表明:球凸的迎风前缘传热能力大大增强,背风后缘及其之后的尾迹区域出现流动分离且传热性能有所减弱;球窝的前缘出现了流动分离且传热性能明显减弱,后半球窝处的分离流体再附使传热能力增强.通道旋转对传热阻力特性的影响很大,主要是旋转使得球窝/球凸表面的流动分离再附提前发生或延迟出现,后缘面流动分离再附频繁出现.比较3种通道发现:竖椭圆球窝/球凸通道和圆形球窝/球凸通道的平均Nu和摩擦系数几乎相等,横椭圆球窝/球凸通道的平均Nu和摩擦系数明显大于圆形、竖椭圆通道.
The influence of the ball-socket / ball-convex structure on the heat transfer and drag characteristics of the channel under rotating conditions was studied by numerical simulation. The viscous Navier-Stokes equation was solved by the SSTk-ω turbulence model. One side of the rectangular channel was arranged ball Convex, the other side of the ball nest layout, ball / ball convex structure is divided into round, vertical oval and horizontal oval.The results show that: ball convex windward front heat transfer capability greatly enhanced, the leeward trailing edge and after The wake region appears flow separation and the heat transfer performance weakened; ball the front edge of the flow separation and the heat transfer performance was significantly weakened after the separation of the hemispherical fissure fluid and then attached to enhance heat transfer capacity. Channel rotation of the heat transfer resistance Characteristics of the major impact is the rotation of the ball / ball convex surface of the flow detachment occurred before or after the delay occurs, the trailing edge flow separates and then appear frequently.Comparison of three kinds of channels found: vertical ellipsoid / ball convex The average Nu and friction coefficient of the channel and the round ball / ball channel are almost equal, and the average Nu and friction coefficient of the transverse elliptical ball / ball channel are obviously larger than that of the circular and vertical ellipse channel.