Pool boiling has the ability to remove large heat flux at low difference temperature of wall and this can be further enhanced by using surface modification methods. This article investigates pool boiling heat transfer on 4 levels with different orientations. For this purpose, a laboratory device was designed and built. The main goal of providing a simple and cost-effective manner with high durability in industrial applications, to having the highest amount of critical heat flux at the lowest level of super-heated temperature difference. The results show that surface roughness factor causing a delay in connecting the bubbles and heat flux increased slightly. In addition to roughness factor, two factors separating bubbles from the fluid in the heat dissipation and more power nucleation sites and micro-bubble layer can be more important than the surface roughness. The surface polished in one direction with lower roughness has higher critical heat flux than circular rough surface. Ultimately to combine bubble separation and more feed the micro layer with made micro channel. With this method it could be increased 131% critical heat flux and 211% heat transfer coefficient.

Keywords: Pool Boiling, Orientation of Surface, Bubble Motion, Critical Heat Flux, Heat Transfer Coefficient

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