TRANSIENT GROWTH OF BUBBLES IN SATURATION BOILING OF PF-5060 DIELECTRIC LIQUID ON ROUGH SURFACES
Experiments are performed to investigate the transient growth of discrete bubbles in saturation nucleate boiling of PF-5060 dielectric liquid on 10×10 mm uniformly heated smooth (Ra = 0.039 μm) and rough (Ra = 0.21-1.79 μm) Copper (Cu) surfaces. Images of growing discrete bubbles, at an applied surface heat flux of ~ 0.5 W/cm2, are captured using high speed video camera at 210 frames per second (fps). On smooth Cu, the determined bubble departure diameter and detachment frequency are 655±53 μm and 31±4 Hz. The bubble departure diameter and detachment frequency on the rough surfaces of 438±36 μm and 38±3 Hz, respectively, are of surface roughness.