스프레이 냉각에 따른 고온 강판의 비등열전달 특성 = Boiling Heat Transfer of Water Spray Cooling on Hot Steel Plate

다국어 초록 (Multilingual Abstract)

Water spray cooling has been used in many engineering applications, especially in hot steel plate cooling of steelmaking plant. The boiling heat transfer characteristics during water spray cooling were investigated by simultaneous boiling visualization and heat transfer measurement. The hot steel plate was uniformly heated up to 900oC and was cooled down by the water spray. The local surface temperature, heat flux and heat transfer coefficient on the hot steel plate was determined by solving 2-dimensional inverse heat conduction with the flat-plate type heat flux gauge. The boiling visualization exhibits when the nucleate boiling starts to occur and turns to collapse the film boiling on the hot steel surface. The measured onset of nucleate boiling agrees well with the corresponding boiling visualization. The cooling uniformity on the hot steel plate can be controlled by spray nozzle height. So the present study can be helpful to provide the design of water spray cooling on hot steel plate.