IR measurements of heat transfer coefficients and nucleation parameters during saturated nucleate boiling of water–glycerin mixtures

• DOI: 10.1016/j.csite.2022.101917
• Publication Date: 2022-03-05T01:12:52Z
• Authors: Viktor Vajc; Matic Može; Matevž Zupančič; Radek Šulc; Iztok Golobič
• Keywords: frekvenca nukleacije; zmes voda-glicerin; vrenje v bazenu; titanova folija; mehurčkasto vrenje; premer mehurčka; Bubble departure diameter; 01 natural sciences; heat transfer coefficient; nucleate boiling; titanium foil; 0103 physical sciences; bubble growth rate; Heat transfer coefficient; infrared thermometry; nucleate boiling, pool boiling, heat transfer coefficient, water–glycerin mixtures, bubble departure diameter, nucleation frequency, bubble growth rate, infrared thermometry, titanium foil; Nucleation frequency; pool boiling; water–glycerin mixtures; info:eu-repo/classification/udc/544.3/.4:66.02; info:eu-repo/classification/udc/544.3/.4; infrardeča termografija; Engineering (General). Civil engineering (General); mehurčkasto vrenje, vrenje v bazenu, koeficient toplotne prestopnosti, zmes voda-glicerin, premer mehurčka, frekvenca nukleacije, rast mehurčka, infrardeča termografija, titanova folija; Water–glycerin mixtures; koeficient toplotne prestopnosti; rast mehurčka; Nucleate boiling; Pool boiling; bubble departure diameter; nucleation frequency; TA1-2040

Heat transfer coefficients and nucleation parameters were experimentally measured during saturated nucleate boiling of water–glycerin mixtures on a thin smooth titanium foil. Infrared thermometry was employed to study boiling of water–glycerin mixtures at atmospheric pressure in water mass fraction range from 100 % down to 60 % and heat flux range from 0 to 200 kW m−2. Heat transfer coefficients were found to deteriorate with an increase of concentration of glycerin in the boiling mixture. The deterioration was more pronounced for mixtures with lower water mass fraction and for higher heat fluxes. Bubble departure diameters were observed to be weakly dependent on heat flux and independent of composition of the boiling mixture. Nucleation frequencies were found to increase with heat flux and to be inversely proportional to water mass fraction of the boiling mixture. Thermal energy transferred during nucleation of individual bubbles was independent of both heat flux and mixture composition. Values and trends of evaluated parameters suggest that for investigated mixtures and boiling conditions, heat transfer into the liquid phase is more important relative to the transport of latent heat by nucleating bubbles.