Influence of the Main Geometric Factors and Air Supply Methods on the Geometry of the Flow-Through Two Phase Layer

Abstract

The main criteria for the development of new highly efficient contact devices are the heat-mass exchange process intensification and the capital expenditure reduction. This scientific paper gives consideration to experimental investigation data obtained for the influence of basic geometric characteristics of vertical channels (channel height and diameter, the aperture diameter and the cross-section area of distribution grating), the influence of the methods and conditions of air supply on the hydraulic resistance of dynamic two-phase flow. It is shown that at relatively small channel diameters (Bo number < 10) the structure of two-phase flow in independent of the method of delivery of gas phase to the working channel. However, as the channel diameter is increased (the Bond number value 10 < Bo < 30) the conditions of delivery of gaseous phase influence the two-phase flow structure. To provide the uniform structure of dynamic two-phase layer in the channel cross-section it is necessary to provide the distributed supply of gas phase through the openings of distribution grating in the bubble device. A change in the height of the working section actually produces no influence on the longitudinal average gradient of total pressure losses. For the practical application of bubble apparatuses the bubble layer is recommended with operation characteristics of liquid and gaseous phase that provide minimum hydraulic resistance for the two-phase layer.