Experimental and Theoretical Analysis of Heat Transfer Characteristics in a Rectangular Duct with Jet Impingement

Abstract

The heat transfer characteristics are analyzed in a rectangular cross section duct where impingement jet technique is applied for the purpose of heating and cooling. Heat transfer characteristics on surfaces are calculated using commercial CFD software, Fluent. Numerical results are compared with the experimental results obtained through a transient liquid crystal technique. To better present the heat transfer results, different cross-sectional size geometric models are used. The geometric models are of six in-line circular jets housed in a confined rectangular channel. As the jet temperature varies with time during a transient test, a time-depended solution method was selected in Fluent. One of the primary varying parameters in the present study is the magnitude of spacing between the jet exit and target plate. The jet Reynolds numbers range from 14,000 to 40,000 for every geometry. The effects of crossflow on the overall flow characteristics in the housed channel and heat transfer distributions on both target surface and jet-issuing plate are investigated. Comparison was made between the present numerical results and experimental data obtained earlier by the lead author, Uysal et al. [1]. The companion experimental study was based on the transient thermochromic liquid crystal (TLC) measurements on detailed local heat transfer distributions on both the target surface and jet-issuing surface.