Experimental research on spray characteristics and heat transfer of cast-rolled strip subjected to impinging air-atomized cooling

Abstract

ABSTRACT Experiments on flow field and heat transfer were carried out to quantitatively analyse the performance of an air-atomized cooling nozzle. A heat transfer platform and a particle image velocimetry system were applied to study the spray characteristics of the nozzle. The effects of water pressure and air pressure on flow rate, spray angle, water flow density and droplets velocity were investigated. The surface heat transfer coefficient (SHTC) was calculated with an inverse heat transfer method based on the instantaneous plate temperature tested by thermocouples. The effects of water pressure, air pressure, jet (nozzle) height, jet (nozzle) spacing and plate temperature on heat transfer of impinging air-atomized cooling were investigated. The experimental research in this paper provides valuable basic reference data for impinging jet cooling. It is of great significance on how to reveal the flow field law of the air-atomized spray nozzle and achieve the best cooling effect.