Research On The Technology Of Direct Evaporative Air Cooler Applying In The Residence Of Northern Villages

Metal fill-type direct evaporative air cooler can be used for cooling, dehumidification purposes of incoming air streams. Compared with traditional air handling equipment, there are many advantages for metal fill-type direct evaporative air cooler. This thesis firstly investigates the theoretical and experimental researches of metal fill-type direct evaporative air cooler's heat and mass transfer performance. And then from the point of view of engineering applications of metal fill-type direct evaporative air cooler in the residence of northern villages, which is directly using the groundwater as the cold source, this thesis investigates the simulation research on the indoor thermal environment of residence of northern villages.Metal fill-type direct evaporative air cooler is tested for their heat and mass transfer performance. The empirical equation of the heat transfer coefficient which provides useful data for further theoretical calculation can be got by dealing with the experimental data. Based on the basic heat and mass transfer theory, the heat and mass transfer on the metal fills'surface is analyzed theoretically by numerical analysis method. The problem's physical and mathematical models are developed. The partial differential equations are discretized and their solutions are found by finite difference method. This thesis gets dry-bulb temperature and wet-bulb temperature of the moist air and the water temperature at every node of metal fills. Combined the experiment results and the theoretical calculation results, the paper analyses the influence of the property of input air and cooled water on the heat transfer coefficient , resistance, the property of output air and water.Then the paper establishes the physical model of representative rural rooms in the cities of Tianjin and Zhengzhou. The cool load and the amount of airflow can be calculated. Then the structure dimension of metal fill-type direct evaporative air cooler can be calculated. Under the most unfavorable conditions in summer, the software Airpak2.1 is used to simulate temperature and velocity fields and thermal comfort of northern rural room. The result of simulation indicates that the metal fill-type direct evaporative air cooler can improve the indoor thermal comfort of the residence of northern villages.