Experimental Determination of the Volumetric Heat Transfer Coefficient in Cooling Towers With Vertical Contact Devices

Intensification of heat and mass transfer processes in industrial drop cooling towers is one of the main areas of research in modern heating engineering. Increasing the efficiency of transfer processes during the direct interaction of water and air in cooling tower sprinklers is possible when moving from creating a contact surface in the form of a flowing liquid film to sprinklers creating drop-film surfaces. One of the possible devices that create such surfaces are devices with vertical contact grids, which make it possible to obtain significant drop surfaces at low energy costs. A mathematical description of mass and heat transfer processes in devices with vertical grids is impossible without the presence of functional dependencies of mass and heat transfer coefficients depending on the hydrodynamic parameters of the process. Obtaining analytical expressions convenient for engineering modeling is difficult due to the complexity of the mathematical description, therefore in some cases it is more convenient to use experimental dependences of the coefficients on the process parameters. The experiments carried out on mass and heat transfer in devices with vertical grids made it possible to confirm the possibility of using the Lewis relation, based on the similarity between the processes of heat and mass transfer under conditions of water cooling in cooling towers equipped with devices with vertical grids. This made it possible to use only one experimental dependence in the mathematical description of transfer processes. An experimental dependence of the volumetric heat transfer coefficient on the hydrodynamic parameters of the interaction of water and air on the contact grids was also obtained.