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چکیده
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Pool boiling can be mentioned as one of the most effective processes of heat transfer regarding the resultant phase change. In this research study, heat transfer in nucleate pool boiling is modeled experimentally with the consideration of surface modification methods utilizing surface photolithography in saturated water at atmospheric pressure. Further, the effects of etching material, confined etched surface, surface area and wettability comparison which is used in fabrication copper surfaces were examined. The images of scanning electron microscopy as well as atomic force microscopy are utilized for obtaining the phase structure and surface morphology in the prepared samples. The experimental results showed that the heat dissipation increases with higher additional area and active nucleation sites densities. Sample with checkered pattern and width of 60 lm created by photolithography process exhibited the maximum enhancement among other samples and the highest heat transfer coefficient, up to 178% compared to the plain surface. Different parameters, including the bubble dynamic, slide and scrape of the bubbles, area of the heat transfer as well as the capillary flow can be considered as the reasons for improved heat transfer. In addition, the bubble dynamic and enhancement mechanisms are investigated based on the images.
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