In this work, we investigate the influence of aluminuim surfaces with different structures on enhanced pool boiling heat transfer of twice distilled water. Individual samples were modified by using different combinations of laser texturing and hydrophobization. An untreated surface, a hydrophobic surface, two hydrophilic surfaces and four biphilic surfaces textured with different laser processing parameters as well as two biphilic surfaces without a hydrophobic coating were experimentally tested. Surfaces were tested on saturated pool boiling experimental setup. Boiling curves up to the CHF values were measured and heat transfer coefficient was calculated. In the analysis, the results were compared with the reference surface (raw aluminium surface). CHF values reached values between 890 kW/m2 and 1480 kW/m2. The highest measured values of CHF and heat transfer coefficient were reached by biphilic surfaces (1480 kW/m2) which represent a 30 % improvement regarding to the reference surface. Heat transfer coefficient improvement reached up to 83 % and achieved the highest value at 61,7 kW/m2K. We have demonstrated that laser-structured biphilic surfaces can improve the pool boiling parameters and can significantly contribute to the improvement of boiling heat transfer.
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