Heat transfer at the stagnation point of the impinging laminar jet

Abstract

Abstract Heat transfer of an impinging axisymmetric jet at low Reynolds numbers (Re = 250-5000) at the obstacle stagnation point was studied experimentally. An air jet from a long tube was flowing onto a flat heated plate at a constant wall temperature. The distance from the jet beginning to the obstacle was h/d = 20. A connection of thermal parameters (averaged and pulsating) at the stagnation point for the flow at the initial cross-section of the jet was established. For the laminar flow, an increase in heat transfer of more than 200% was observed in the jet in comparison with the turbulent flow. Comparison of the obtained data on heat transfer revealed a significant discrepancy with the well-known correlation formula for impinging jets.