The analysis concerns the heat transfer of boiling Fluorinert FC-72 on a stainless steel fin surface modified with a high-powered laser beam. A thermovision camera was used to measure the temperature field at the surface of the fin. Local parameters of the heat transfer were determined by reducing the problem to a boundary one. Due to low conductivity of the material and high values of the heat transfer coefficient in the nucleate boiling regime, the Biot number was much higher than 0.1, which required solving a 2D Laplace equation. The heat polynomials method was applied in the calculations. The validation of the method applied to solve the boundary problem was analyzed using the example of a copper fin operating under the same conditions as those used for the stainless steel fin. The calculations performed for the stainless steel elements confirm the assumptions, and the numerically determined surface temperature distributions coincide with the measured ones. The boiling curve plotted for the laser-modified surface was compared with one obtained for a smooth surface. The surface modification contributes to an increase in boiling heat transfer, and the process of nucleate boiling begins at relatively low values of wall superheat. At high wall superheat, the boiling curves plotted for the modified and unmodified surfaces coincide.
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