Vasylenko S. Heat Transfer in Vapor-Liquid Flows of Food Productions Heat Exchangers

Results of integrated theoretical and experimental research have been presented in the thesis concerning heat-hydrodynamic characteristics of falling annular vapor-liquid flow with evaporation and free jet flows that form during outflow of a liquid from distribution devices of slit-like type. New procedures have been developed of heat exchange and hydrodynamics computation of these flows based on semi-empirical mathematical models on the basis of proposed for the first time principle of intermittency of pulse and energy transfer in films and in free liquid sheets. Empirical relationships have been obtained for calculation of heat exchange in falling annular vapor-liquid flows, in jets and sheets of water during condensation of vapor at their surface, as well as relationship for calculation of heat exchange during vapor condensation from a mixture with incondensable gases at surface of jets. It has been developed model of interphase interaction in falling annular flows and empirical relationship for calculation of equivalent surface roughness of a liquid surface. Relation has been obtained to determine limits of a jet destruction start and one that takes into account dynamic impact of vapor flow on its movement.Procedure has been developed of heat-hydraulic computation of film evaporators. New designs have been developed of heat-mass exchangers with direct phases contact and procedures of theirs computation and assessment of efficiency. Key words: annular vapor-liquid flows, films, jets, interphase interaction, evaporation, condensation, heat exchange, hydrodynamics, turbulence, intermittency, heat exchangers.