Continuous improvement of cooling for power installations dictates efficient ways of transmitting extensive heat fluxes, which is why a mechanism of nucleate boiling of water mixtures is often used to control assemblies. This doctoral thesis experimentally deals with the boiling of two n-butanol aqueous solutions on a 12,5 μm titanium foil and of two mixtures of ethanol and water on differently treated 25 μm stainless foils. The measurements taken represent a step towards a better understanding and to the evaluation of subcooled and saturated nucleate boiling with different concentrations of aqueous solutions with higher-carbon alcohols. Based on the measurements of non-stationary temperature fields with IR thermography, a different approach has been introduced to the treatment of the process of boiling mixtures, whereby the impact of adding small concentrations of higher-carbon alcohols to the thermal characteristic has been confirmed. Further local analysis of saturated boiling based on the observation of growth and frequencies of bubbles using synchronous high speed video recordings and of the temperatures measured by high-speed IR thermography has demonstrated the impact of surrounding fluid depletion. This enabled us to obtain precise information on the circumstances of the life cycle of a bubble. The process of boiling water ethanol mixture on a surface not laser-treated compared to boiling the same mixture on a laser structured surface was significantly influenced by the structure of the surface. The measurements on the laser-treated surface have revealed an increase of active nucleation sites, a reduction in the size of bubbles and an increase in nucleation frequency as well as a reduction in surface overheating. Considering all of the results, the measurements on the treated and non-treated surface for saturated and subcooled boiling of mixtures have demonstrated an important impact of surface laser treatment with a significant improvement in heat transfer.
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