Effect of Cooling Water Temperature on Impinging Jet Heat Transfer on Hot Steel Plate

Water impinging jet has been widely used in a variety of engineering applications; especially in the hot steel cooling of steelmaking processes and heat treatment in hot metals. The effects of cooling water temperature on water impinging jet cooling are mainly investigated for hot steel plate cooling in this study. The heat flux are measured by a novel experimental technique that has a function of high-temperature heat flux gauge in which test block assemblies are used to measure the heat flux distributions on the hot surface. The water impinging jet is produced by a straight pipe nozzle and experiments are performed at fixed water flow rate and fixed nozzle-to-target spacing. The results show that effects of water temperature on impinging jet transfer characteristics are presented for five different water temperatures between 5 to 45°C. The heat flux curves and heat transfer coefficients are also provided to a benchmark data for the actual impinging jet cooling applications of hot steel plate.