Simulation of Heat Transfer Characteristics in Channel with Square Rib Under Uniform and Turbulent Inlet Conditions
The detailed flow structures and closely-related heat transfer characteristics are investigated along the wall of a cooling channel with rib tabulator by computation. Three typical Reynolds numbers defined by the rib height are set at 200,500,1 300,and the Mach numbers is 0.2,respectively. Two inlet boundary conditions,including the uniform and the fully-developed turbulent conditions,are used to study the turbulence effects on the characteristics of heat transfer in the vicinity of rib and wall. Results show that the local Nusselt number increases when the Reynolds number rises from 200 to 1 300. At lower Reynolds number,the turbulent inlet condition generates more tangible heat transfer enhancement. At higher Reynolds number,however,the uniform inlet condition contributes more to the convective heat transfer effects. The paper discovers that the high Nusselt number has a consistent correlation with the positive and negative sign alteration of the shear layer on the wall,which satisfactorily explains the mechanisms of heat transfer enhancement due to the flow.