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The effi ciency of heat and mass transfer in the bubbling bed on the plate has been investigated with the use of the method of combined physical and mathematical modeling based on the representation of the physical process in the form of a combination of elementary phenomena having a hierarchy of scales that permits realizing a scale transition in designing a contact device. The mathematical modeling of the heat and mass transfer in the above bed is based on the idea that the structure of this bed is invariant with its size and the interaction of the phases in it. A parametric investigation of the interaction of various effects in the process of heat and mass transfer in the bubbling bed on the plate and their conjugation has been carried out on the basis of the variational formulation of the conservation laws. Examples of calculating the effi ciencies of the heat and mass transfer processes on bubbling plates are given. The results of calculations were compared with the corresponding experimental data.Introduction. To realize the heat and mass transfer processes in various branches of industry, platelike column apparatuses are used. The effi ciency of operation of bubbling plates in such an apparatus determines both the quality of mixture separation in it and the expenditure of energy in realizing the separation process, as well as the sizes of the apparatus and its metal consumption. The effi ciency of the bubbling plate is determined by its design and the hydrodynamics of the bubbling bed on it. Such a contact device should be designed taking into account that it should provide the required structure of the fl ow and a high effi ciency of interaction of the plates in it. In most cases, to solve this problem, physical modeling of the heat and mass transfer on the plate model and mathematical modeling of the fl ow structures in its bubbling bed are carried out. On the basis of the obtained data, the effi ciency of the plate and the methods for upgrading it by changing the plate design and the hydrodynamics of the bubbling bed are determined.To determine the structure of the fl ows in the bubbling bed on the plate, combined models are used widely. In these models, cells of complete mixing of the phases, diffusion zones, and bypass and circulation fl ows are simulated. The parameters of the combined model of the plate are determined experimentally on its model and then are corrected on pilot semifi nished and fi nished production prototypes or by hydrodynamical simulation of the investigated process in a facility of natural diameter but smaller in height than the commercial-scale column. Correction of the model parameters in going from the model to the production prototype is carried out mathematically on the basis of the momentum and mass conservation laws for the bubbling bed written in the differential form that are invariant with scale of the plate. The use of a single methodology combining the physical and mathematical modeling of the contact device is the most rational way of designing it [1][2][3][4][5][6]....

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