Heat Transfer and Crossflow Investigations for Jet Impingement Cooling Applications

Abstract

Jet impingement is widely used in different cooling applications. The accumulation of crossflow as the spent air migrates downstream causes a decay in the overall cooling performance. This study aims to mitigate the undesirable crossflow effects by attaching the so-called-crossflow diverters. Cylindrical, rectangular, and ribbed diverter shapes are numerically studied within a 25-jet array for a range of Rej of up to 10,000. Diverter heights of 3 mm (QL), 6 mm (HL), and 9 mm (TQL), as a percentage of jet-to-target spacing (12 mm) are considered with a constant heat flux condition. Results show an increased Nu from 6.6% to 12%. However, the associated friction factor is also increased by 9.9% -24.3% on average compared to the baseline model. Consequently, results show a net enhancement of up to 5.2%, 3.1%, and 3.8% for cylindrical, rectangular, and ribbed-type diverters, respectively according to the heat transfer performance parameter (η).