Research Of Thermal And Mass Transfer Performance Inside Solution Regenerator

The emergence of refrigeration and air conditioning technology provides a very comfortable life environment for people, but due to some technical problems the traditional refrigeration and air conditioning equipment brings serious environmental and energy problems. Temperature and humidity independent control air conditioning system is a new type of energy-saving air conditioning system. Dehumidifier and regenerator is a major part of the temperature and humidity independent control system. This article mainly discusses the solution regenerator internal mechanism of heat and mass transfer theory and numerical simulation research. In order to maximize the condensing heat for heat source of solution regenerator performance, thereby enhancing the working efficiency of the air conditioning systems, change rules of outlet parameters are explored on the conditions of different inlet boundary conditions of solution regenerative evaporative condenser.Firstly, based on the heat and mass transfer theory and computational fluid dynamics equation, theory of evaporative condenser with liquid regeneration is researched, heat and mass transfer mathematical model and the basic control equation are established, the finite volume method is adopted in the second order discrete form of windward format equation, geometry and grid model is set up, speed and wall boundary conditions are set, and FLUENT software is uses for simulation.Secondly, typical condition of evaporative condenser with solution regeneration is made simulation and analyzed to get the internal air flow field, air temperature field, droplet motion and momentum distribution. The results show that air in coil form a high-speed flow around and strengthen heat and mass transfer between gas and liquid by using triangular cross type coil; The solution form liquid film on the tube bundle, the regional air and solution heat and mass transfer is obvious at the bottom; The air temperature increases with the flow direction, air temperature in middle area is higher than on both sides of the temperature; Droplets passing momentum in the X direction distribution more uniform, but in the Y direction is obvious oblique distribution.Finally, the impact of the different inlet velocity, temperature and concentration of the solution and air inlet velocity and temperature on the outlet air and the solution parameters of evaporative condenser with solution regeneration are explored. And two wall heating modes the constant wall temperature thermal boundary condition and the constant heat flux thermal boundary condition are made comparative analysis. The results show that with the increase of solution inlet velocity, the outlet temperature of the lithium chloride solution is reduced, and with the increase of export concentration, the air outlet moisture content and air outlet temperature is lower; With the increase of solution inlet temperature, export of lithium chloride solution concentration and temperature increases, and the air outlet moisture content and temperature is increased; With the increase of solution inlet concentration, export of lithium chloride solution concentration and temperature increases, the air outlet moisture content decreases, the air outlet temperature increase; With air inlet velocity increases, the outlet temperature of the lithium chloride solution and export concentration decreases, the air outlet moisture content slowly increase at first and then have a sharp decline, export air temperature increases; With the increase of air inlet temperature, outlet temperature of the lithium chloride solution increase, export concentration showed a trend of increase, air moisture content and air outlet temperature increase. Compared with the results of simulation by constant heat flux boundary condition, the results through constant wall temperature boundary conditions are higher including the outlet temperature of the solution, the air outlet temperature and quantity of air outlet humidity. Regenerator inlet speed of lithium chloride solution has the greatest influence on the regenerator outlet parameters, followed by the lithium chloride solution inlet temperature, finally the inlet air flow rate. Because linear convection heat transfer is adopted by constant heat flux boundary condition and the law conforms to the actual situation.