Submicron characterization of transient temperature fields on boiling surfaces represents a major challenge in the study of heat transfer during nucleate boiling. This thesis examines various approaches to micro- and nanothermometry, with a particular focus on fluorescence thermometry, which has emerged as one of the most promising methods due to its high spatial and temporal resolution and non-intrusive nature. Based on a review of the literature and analysis of current methods, we designed an experimental system enabling controlled generation of a nucleation site by means of optical tweezers. Experiments were performed in the dielectric fluid Thermasolv IM2, doped with europium-based particles that act as temperature-sensitive fluorescent markers. Light with a wavelength of 385 nm was used for excitation, while the emitted fluorescence signal was selectively separated using optical filters. The developed system allows for reliable observation of the spatial and temporal dynamics of temperature fields and opens new opportunities for further studies of fundamental boiling mechanisms as well as for the development of advanced cooling strategies in micro- and nanoelectronics.
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