Heat transfer from a hot steel plate impinged by air-atomized water jet and impinging water jet

Abstract

Thermo-mechanical controlled process (TMCP) technology has been widely used to improve the mechanical properties of hot-rolled steel plate. Laminar cooling has been the main cooling form in the steel mills. However, the performance of laminar cooling is limited by its low cooling capacity, nonunifor-mity, and inefficiency. In this work, it was demonstrated that the air-atomized water jet can be applied in the hot-rolled plate manufacturing process with excellent cooling performance. The cooling efficiency of the steel plate (700°C) was significantly improved by applying air-atomized jet (AJ) with different water densities compared with impinging jet (IJ). Moreover, the local spray density, boiling curves at different positions and the corresponding average heat flux of both cooling methods were systematically investigated by mathematical correlations. The experimental data in this study would be beneficial for design and simulation of the cooling device to achieve better cooling rate and uniformity.