The constant search for techniques that optimize the process of heat transfer, including phase-change, requires the study of the dynamics of the vapor bubble in the nucleate boiling process. Thus, the present work has the objective of studying the mechanisms of heat transfer in the nucleate boiling regime by experimental tests on a plain copper surface with artificial cavity, analyzing the steps of growth and departure of the vapor bubble. The research will be developed together with a master's project, involving the development of experimental techniques and analysis of results. Aspects concerning the formation and growth of vapor bubbles will be studied by analysis of the experimental data (diameter and departure frequency of the bubbles) and visualization of the boiling phenomenon, including the development of an optical sensor that is affordable and non-intrusive, thus ensuring the absence of any direct interference in the measurements of the obtained signals and, consequently, in the characteristic frequencies of the bubbles. HFE-7100 will be analyzed at saturated conditions. In addition, the present study will also involve the characterization of the tested surface using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The contribution of this work is to obtain results that combine fundamental and applied research whose incorporation by the industry results in more efficient equipment from an environmental and energy point of view. In addition, the use of an optical sensor, whose electronic component architecture is built to convert the analog signal into digital, allows greater reliability of the conversion in the domain of stationary or varied frequencies over time obtained through linear analyzes such as Fourier and wavelet transforms, respectively.
News published in Agência FAPESP Newsletter about the scholarship: