倾斜矩形通道中湍流混合对流换热的数值分析

Numerical Study on Turbulent Mixed Convection in Inclined Rectangular Channels

在文献中对重力影响的湍流流动与换热的分析,多数集中在对竖直通道的研究,少有述及倾斜角度的影响。本文针对倾斜矩形通道中的湍流混合对流进行了数值分析,以考察倾斜角度对流动和传热的影响。分别分析了空气向上流动和向下流动的工况,倾斜角度的调整范围在15°～90°之间,矩形通道的下侧板单侧进行加热。采用了数种两方程湍流模型(k-ε模型),通过与文献中的竖直通道混合对流实验数据进行比较分析,以确定最为合适的湍流模型。然后,基于这个湍流模型对倾斜的工况进行研究。文中主要考察了倾斜角度分别在向上流动和向下流动中对沿程努塞尔数(Nu)的影响。

In literatures, the analysis of turbulent flows and heat transfer with buoyant effects mainly focus on the Study on vertical channel. Although the flows in inclined channel can be encountered everywhere in engineering condition, it has not drawn much attention. In this paper, numerical study on turbulent mixed convection in inclined plane channel has been made to examine the effect of inclination on fluid flow and heat transfer distributions. The inclination angle is changed from 15°to 90°. The turbulent air flows upward or downward into the duct with one wall heated from below. Calculation results with several kind of k- ε type turbulence models （called k- ε model） have been used to compare with the experimental data in opening literatures to determine which is the most suitable model to adopt. The dependents of Nusselt number on the inclination angle of both the buoyancy-aided and buoyancy-opposed flow are discussed.