Paper Title
Effect on Surface Vibration on Flow Boiling Heat Transfer of R-600a in a Vertical/Parallel Circular Tube with Metallic Porous Inserts

Abstract
This study carried out an experiment to investigate the characteristics of sub-cooled flow boiling heat transferof a hydrocarbon refrigerant R600a (isobutane) flowing in a vertical circular pipe within dispersed-copper porous inserts under surface vibration. The experiment was performed at a saturation temperature of 10°C. Vapor qualities were from 0.076 to 0.89, and there was a mass flux of 105 – 1085 and a heat flux of 12-65 . The effects of surface vibration and the geometries of the inserts (the mean pore diameters, porosity and permeability) on the heat transferof R-600a were presented. In addition, comparisons were made with a horizontal pipe having the same geometry and experimental conditions Index Terms - R600a,vertical/ parallel flow boiling, heat transfer, surface vibration, dispersed-copper porous inserts sixth term