Pengaruh Sudut Kontak Statis Terhadap Dinamika Penjalaran Droplet yang Menumbuk Permukaan Panas di Atas Kondisi Wetting Limit Temperature dan Bilangan Weber Menengah

Abstract

The effect of static contact angles on the spreading of droplet above wetting limit temperature has been studied experimentally. The various of cantact angles achived by using surface with treatments, they were stainless steel, stainless steel coated with TiO2 without UV light and stainless steel coated with TiO2 with UV light. Droplet substance was destilated water with initial diameter 2,41 mm. Impact energy was expressed in Weber number, they were 50,27; 60,85; and 71,44. Solid surface temperature was varied from 250−400oC with 5oC interval. As result, it was known that spreading factor increases due to the decreasing of static contact angle and increasing of Weber number. For the condition above wetting limit temperature, spreading factor increases due to the decreasing of static contact angle and the increasing of Weber number until radial breakup limit temperature. Above radial breakup limit temperature, spreading factor decreases due to the decreasing of static contact angle and the increasing of Weber number.