Boiling is considered as one of the processes with the most effective heat removal. It enables high heat fluxes at relatively low temperature differences. Bubble nucleation reperesents the key mechanism of the process; therefore, it is vital to be familiar with factors that influence nucleate boiling process and understand them. This thesis investigates the pool boiling process on vertically oriented, stainless steel surfaces, using IR thermographic analysis. Laser texturing and the hydrophobic coating was used to fabricate three samples – one with hydrophilic, one with hydrophobic nucleation spot and one with three hydrophilic spots. Using an experimental setup, we performed measurements on samples for three different subcooling, of water bulk – 1, 4, and 9 K. The sample was exposed to heat fluxes between 70 and 130 kW m-2.. We found that local boiling surface temperatures and heat fluxes increase with the decrease of subcooling and the increase of the heat flux that the sample is exposed to. At the same time, with the increase of subcooling and decrease of exposure heat flux, bubble diameters are reduced.
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