화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.48, No.25-26, 5395-5407, 2005
Delay of wetting propagation during jet impingement quenching for a high temperature surface
Transient heat transfer has been investigated experimentally with a subcooled water jet during quenching of hot cylindrical blocks made of copper, brass and steel for initial surface temperatures from 250 to 400 degrees C. The jet velocity was from 3 to 15 m/s and jet subcooling from 5 to 80 K with a jet diameter of 2 mm. When the jet strikes the hot surface, the wetting front becomes stagnant for a certain period of time in a small central region before wetting the entire surface. This wetting delay may be described as the resident time which is a strong function of block material and jet subcooling and also a function of initial block temperature and jet velocity. New correlations for the resident time and the surface temperature at the resident time at the wetting front have been proposed. (c) 2005 Elsevier Ltd. All rights reserved.