COMPUTATIONAL ANALYSIS OF FLOW AND HEAT TRANSFER IN PASSAGES WITH ATTACHED AND DETACHED RIB ARRAYS

摘要

This paper presents the results of a numerical investigation of heat transfer and friction for the flow of air in passages with attached and detached rib arrays. This technique is used in internal cooling methods. Four geometric configurations are used in the calculations. The governing equations are solved in a two-dimensional domain using a finite-volume formulation. The SIMPLE algorithm for the velocity-pressure coupling is employed. The results are obtained for Reynolds numbers ranging from 200 to 1000. The rib height and rib width-to-channel hydraulic diameter, detached distance-to-height rib ratio, pitch-to-height rib ratio, and Prandtl number are fixed ath = w = 0.2, C = 0.5, p = 10, and Pr = 0.71, respectively. The grid is nonuniform and highly concentrated close to the rib to capture high gradient velocity, pressure, and temperature. A uniform temperature through the ribs and all walls was assumed. The interaction between the hy-drodynamic and thermal structures is developed. The effect of geometrical configurations onflow and heat transfer has been detailed by a systematic analysis. We have determined the distributions of velocity, friction factor, temperature, and Nusselt number according to the different geometrical configurations and Reynolds numbers. 【keyworks】 roughened passages;attached and detached ribs;symmetric and staggered ribs;heat trans-fer enhancement;finite-volume formulation