Features of heat transfer at interaction of an impact swirl jet with a dimple

Abstract

Experimental results on investigation of heat transfer at interaction of an air impact jet with a semi-spherical cavity are presented in this work. This research is continuation of investigations of turbulent jet interaction with complex surfaces and search for the method of heat transfer control. Experiments were carried out with fixed geometry of a semi-spherical cavity (DC = 46 mm) and swirl parameter (R = 0; 0.58; 1.0; 2.74). The distance between the axisymmetric nozzle and obstacle was 2?10 sizes over the nozzle diameter, and the Reynolds number varied within Re0= (1?6)?104. It was found out that with an increase in swirling heat transfer intensity decreases because of fast mixing of the jet with ambient medium. In general, the pattern of swirl jet interaction with a concave surface is complex and multifactor.