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Information × Registration Number 0224U031757, 0118U007153 , R & D reports Title Heat Transfer Modeling in annular down flowing steam-liquid streams in viscous sugar solutions during evaporation popup.stage_title Head Petrenko Valentyn P., Доктор технічних наук Registration Date 11-06-2024 Organization National university of food technologies popup.description2  ABSTRACT Report on the GDR: 55 pp., 21 figs. 3 applications MATHEMATICAL MODELING, HEAT EXCHANGE, FILMS, ANNULAR FLOWS, BOILING, TURBULENCE, CONCENTRATION, SURFACE WAVES, TEMPERATURE FIELD A mathematical model of the process of heat transfer in a liquid film flowing down a vertical surface with a developed structure of low-frequency waves of large amplitude has been developed. The periodic process of disturbance and reproduction of the temperature field in the film after the passage of large waves on the surface of flowing liquid films is considered. The temperature field is obtained as a result of the approximate solution of the equation of convective heat conduction with turbulence in the film with the boundary conditions under which vaporization occurs at the interfacial surface. A comprehensive theoretical and experimental study of the processes of heat transfer to downward annular vapor-liquid flows of weakly and highly concentrated sugar solutions was carried out. The range of changes in the parameters under which the studies were performed: syrup concentration - from 0 to 75%, pressure up to 0.8 bar, rarefaction up to 0.84 bar, irrigation density from 0.05 kg/m s to 0.6 kg/m s , steam velocities from 0.5 to 45 m/s, heat flow density from 2 to 60 kW/m2 for water and from 2 to 40 kW/m2 for syrups, temperature head from 2 to 20 oС. The results of the theoretical analysis formed the basis of the development of correlations and their generalization of a set of experimental data obtained both on installations with artificial formation of a two-phase flow and on installations simulating real conditions of concentration of syrups in the tubes of evaporators. Approximation ratio (51) is recommended for engineering calculations of the intensity of heat transfer to annular downward flows of solutions. Based on the results of the research, 9 articles were published (including 3 articles in the journals of the Web of Science scientific-metric database), 4 reports at in Product Description popup.authors Petrenko Valentyn P. popup.nrat_date 2024-06-11 Close