Effect of chamfered nozzle geometry on impinging jet flow

The widespread usage of impingement cooling makes this technique popular. From simple hand drier to advanced gas turbine, most of the industries use this technique for drying or cooling. Therefore, many studies both experimental and numerical are conducted to study every aspect of this technique. However, for optimum usage of this technique, the affecting parameters should be analyzed and designed accordingly. There are important parameters, which directly influences the heat transfer efficiency of jet impingement. These nozzle parameters are Reynolds number, depending on the flow speed and sizing of the jet nozzle, Mach number, jet-to-target spacing, jet-to-jet spacing and finally jet geometry. So far, variety of geometries have been tried and analyzed to study the flow structures and contribution to the heat transfer. Because, studying the flow structures would bring us at the end to the optimum shape of efficient heat transfer by impinging jet technique. Through this study another jet geometry, which is the chamfered, was studied. The experimental study was conducted by 00, 300 and 450 chamfered nozzles for two different Reynolds number (9,600 and 19,200) and for three different jet-to-target spacings (H/dn = 4, 6, 10) to observe the effect of these parameters. To understand the flow field, hot wire anemometer measurements were conducted and backed up with pressure measuerements.