Study On Flow Characteristics And Heat Transfer Of Bulge-plate Evaporative Condenser

It was an effective measure of developing new energy sources and improving energy efficiency of the existing equipment to solve the energy issues. Evaporative conde nser was a high efficiency and energy-saving heat exchanger. Its condensing temperature was 4~10 ℃ lower than that of the water-cooled condenser, and its power consumption was 40% of water-cooled condenser’s. Compared with air cooled-condenser, its condensing temperature was 8~11℃ lower, and power consumption was reduced by about 40%. Evaporative condenser was widely used in various industries because of the advantages of saving water and electricity. This paper presents the results of the research on the evaporative condenser:Based on the periodic bump plate evaporative condenser water chiller performance testing, get the inlet and outlet temperature of refrigerant, surface temperature of plate, and wet and dry bulb temperature of inlet and outlet air, i.e. The cooling capacity of the unit was 750 k W, the heat flux was 2975 k W/m2, and energy efficiency of the unit was 3.86. The result showed that cooling capacity, heat flux and energy efficiency of the unit increased with the increase of the chilled water outlet temperature.The Fluent software was used to conduct the numerical simulation for predicting the course of evaporation between air and water in evaporative condenser. And then studies on influencing factors of humidity ratio, pressure difference and s urface heat transfer coefficient, i.e., air velocity mass, flux of cooling water and plate structure were conducted. Heat and mass transfer was enhanced when the air velocity increased from 0.5m/s to 4m/s. With the increase of mass flux of cooling water, the pressure difference increased, and the outlet temperature decreased, and humidity ratio of outlet air decreased from 0.0276 kg/kg to 0.0278 kg/kg. With the increase of plate diameter, the amount of water evaporation reduced, and the loss of energy decreased. The intensity of heat and mass transfer decreased after the first increase of the temperature of plate angle. The maximum temperature of the outlet air was 303.5K and the maximum humidity ratio of the outlet air was 0.027 kg/kg when angel was 165°.The CFD software was applied to conduct the numerical simulation for predicting the air velocity, pressure, and temperature, humidity ratio in the corrugated filler which was used in evaporative condenser. And then studies on influencing factors of humidity ratio, pressure difference and surface heat transfer coefficient, i.e., filler space, air velocity and mass flux of cooling water were conducted. Simulation results were verified through experiments. The results showed that it contributed to heat and mass transfer and lower energy consumption when air velocity was 2m/s, filler space was 6mm.