Heat transfer characteristics of water spray impinging on high temperature stainless steel plate with finite thickness

Abstract

Experiments for full cone water spray cooling of high temperature metal plate are carried out at different water pressure levels. The heat flux is obtained by solving a 1D inverse heat conduction problem, and the accuracy of the heat flux is verified by 3D heat conduction analysis. Water flux significantly influences transition boiling, critical heat flux, and Leidenfrost point, with the increase in water pressure driving critical heat flux and Leidenfrost point to a higher surface temperature region. By contrast, water flux has very limited effect on nucleate boiling regime, and all the heat flux curves merge into a narrow band. The heat flux in the nucleate boiling regime is mainly depends on surface temperature. The empirical correlations for critical heat flux and transition boiling regime are obtained as function of Sauter mean diameter, local water flux, surface temperature, and physical properties of water and vapor. The local water flux is suitable for obtaining the local heat transfer characteristics of spray cooling, given that the spatial distribution of spray flux is non-uniform.