旋转弯管内耦合对流换热特性研究

Flow structure and combined free and forced convective heat transfer in rotating curved pipe

由于离心力,科氏力,和离心型浮力(Centrifugal-typeBuoyancyforce)同时出现,使得旋转弯管内的流动和换热特性更为复杂。本文考虑了温度与密度的耦合关系,对旋转弯管的对流换热问题进行了数值研究。分析了不同F数(科氏力和离心力之比),RaΩ数(旋转Rayleigh数),以及Ro数(Rossby数)下的二次流动、轴向主流、温度场、摩擦系数比、努塞特数比变化规律。为工程上解决旋转弯管道内耦合对流换热问题提供了可靠的理论依据。

When a temperatureinduced variation of fluid density occurs in a rotating curved pipe, Corlolis force, centrifugaltype buoyancy force and centrifugal force could contribute to the generation of the secondary flow. The nonlinear interaction of these body forces complicate the flow characteristics. A numerical study on combined free and forced convective heat transfer and flow characteristics are made on this paper. the variations of flow and temperature field structure , the friction factor ratio, the Nusselt number ratio on different F(the ratio of Coriolis force and centrifugal forces ),Ro (the Rossby number), and RaΩ(the rotating Reyleigh number) are shown.