Effects of Nozzle-Inlet Chamfering on Pressure Drop and Heat Transfer in Confined Air Jet Impingement

Luis A. Brignoni
S V. Garimella, Purdue University

Document Type Article

This document is available at http://docs.lib.purdue.edu/coolingpubs/61


The effect of changing the nozzle geometry on the pressure drop and local heat transfer distribution in confined air jet impingement on a small heat source was experimentally investigated. Heat transfer and pressure drop measurements obtained with chamfered nozzles were compared to those obtained with a square-edged (non-chamfered) nozzle of the same diameter for different turbulent Reynolds numbers in the range of 5000±20,000, nozzle-to-target spacings, chamfer angles and chamfer lengths. The ratio of average heat transfer coefficient to pressure drop was enhanced by as much as 30.8% as a result of chamfering the nozzle, with narrow chamfering providing the better performance.