Experimental investigation of heat transfer in a falling down rivulet of liquid FC-72 on the vertical heated foil

Abstract

Heat transfer at rivulet FC-72 flow over the constantan vertical heated foil with the length of 80 mm, width of 35 mm, and thickness of 25 mm was studied experimentally. Distributions of temperature on the bottom side of foil from the rivulet flow using the infrared thermographic data were obtained. In the future heat flux from the foil will be calculated with help of Koshi problem solution. It was shown that the rivulet width as the liquid flow rate increases, and it narrows as heat power increases due to the high evaporation rate. In the case with water, the rivulet narrows not so intensively as compared with the rivulet of FC-72 liquid. Good wettability and low heat of vaporization of FC-72 liquid contribute to using it to develop effective cooling systems.