Experimental Study on Cooling a Hot Solid Surface with Water Mist

In this paper, a series of experiments are performed to investigate the hot solid surface cooling with water mist under different conditions, such as different initial surface temperatures and mist characteristics (droplet size, droplet velocity, etc.), while these parameters are simultaneously varied. A 150 150 10mm 3chrome-plated stainless steel plate is heated from below by a 1500-W electric cooker continuously. A downward pressure nozzle is positioned on a square steel plate, 1000mm above the surface to inject water mist, the 0.5mm K-type thermocouples are jointed on the surface to obtain its temperature, and a TVS-2000ST Thermography is used to visualize the transient thermal behavior of a water mist and obtain the temperature distribution of the surface. The characteristics of the water mist are obtained by a modified PIVS (Particle Image Velocimetry and Sizing) technique previously. Based on the experiments, the effects of mist parameters and the initial surface temperature on droplet evaporative cooling are analyzed. Further discussion is carried out by considering the relationship between these parameters and the droplet Weber number, the results show that an inverse relationship between the cooling efficiency and mist droplet Weber number existed in this study.