Experimental and numerical investigations on heat transfer enhancement using flow deflectors in a jet array impingement system with cross flow

Abstract

Multi-jet impingement heat transfer is of special interest to engineers as high heat transfer newlinerates can be attained in the impingement areas. Despite several applications in electronic newlinecooling and other industries, cross-flow assisted jet impingement in the presence of flow newlinedeflectors such as baffles and vortex generators have not been studied adequately in the newlinepast. With the major focus on cooling of a heated surface subjected to constant heat flux newlinecondition, the following two concepts were considered: (i) multi-jet impingement in newlinepresence of cross-flow and three types of baffles- Segmented, Split and Louver newlineconfigurations, and (ii) multi-jet impingement in presence of cross flow and two types of newlinevortex generator pairs- Rectangular and Delta configurations. Experimental, numerical newlineand statistical studies have been carried out to analyze the fluid flow characteristics. An newlineexperimental test set-up has been established specifically for the purpose of newlineexperimenting each case for varying operational parameters as well as validating the newlinenumerical predictions. A commercial software ANSYS FLUENT has been employed for newlinethe numerical study to simulate three-dimensional turbulent flow field and heat transfer newlinecoupled with SST k-and#969; turbulence model. Correlation and regression analysis have been newlineused to relate operating parameters with desired outputs. The present study also deals newlinewith determination of optimal operating parameters with the help of Genetic Algorithm newline(GA) and Artificial Neural Network (ANN) concepts. The parametric study newlineof baffle clearance shows that louvered baffle configuration is more effective in terms of newlinethermo-hydraulic performance, in the range of baffle clearance analyzed in this study. newline