旋转矩形截面螺旋管内对流传热特性的研究  

Characteristics of fluid flow and heat transfer in a rot ating helical rectangle duct

作　　者：陈华军[1] 沈新荣[1] 苏霄燕[1] 章本照[1] 

机构地区：[1]浙江大学力学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2003年第4期445-449,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(10272096).

摘　　要：利用数值计算方法研究了旋转矩形截面螺旋管内的粘性流动,分析了在离心力、科氏力共同作用下曲线管道中的二次流动结构、轴向流速分布、截面温度分布、摩擦系数比以及管道Nusselt系数数比随各参数的变化情况.计算结果表明:对于不同截面的矩形螺旋管道,当旋转方向和主流方向相同时,旋转的作用与增大Germano数的作用相同,使得管道摩擦系数变大,管道换热效果增强;而当旋转方向和主流方向相反时,管道内流动结构变化十分明显,当F≈-1.3时,二次流出现类似于直扭管内的鞍状流动结构,轴向速度类似与静止直管内的流动结构,管道内的摩擦系数近似于静止直管内的磨擦系数,换热效果减至最弱.An incompressible viscous steady flow through a rotating helical rectangular duct was studied numerically. The effects of rotation on the secondary flow structure, the distribution of cross temperature, the friction factor ratio and the Nusselt number ratio were examined for different aspect ratios. The results indicated that the rotation had evident effects on the fluid flow and heat transfer. When the rotation was in the same direction as the axial velocity, the effect of rotation was similar to that caused by increasing the Dean number, but when the rotation was in the opposite direction of the axial velocity, there was an evident difference in the effects on fluid flow and heat transfer. When F (the ratio of the Coriolis force to the centrifugal force) was about -1.3, the friction factor and the Nusselt number reached their minimum values and the flow behavior is similar to that in stationary twist ducts.

关 键 词：旋转矩形截面螺旋管 对流传热 粘性流动 离心力 科氏力 二次流动 流速分布 温度分布 

分 类 号：TK124[动力工程及工程热物理—工程热物理]