Preliminary Experimental Study On The Single-tube And The Single-sheet Of Water Film Evaporative Air Cooler

Water film evaporative air cooler is a kind of device which can save energy and water. It will be the important direction for air-cooling in the future. This paper based on the film-increasing type evaporative air cooler. Take out the single-tube and the single-sheet from the equipment on the experiment for some rules.Measured the temperature on the different angles of the heat exchange tube and the temperature on the different heights of the sheet under the different spray quantities, the different diameters, the different tube internal heat water temperature and the different wind speeds out of the tube. The datas indicated that, as the spray quantity increases, the diameter decreases, the tube internal heat water temperature decreases and forced ventilation, the temperature is lower not only on the tube but aslo on the sheet.Researched the local heat transfer coefficient on the tube and the sheet under the different conditions. Indicated that, on the tube, as the spray quantitiy increases, the local heat transfer coefficient increases first and then decreases, and when the spray quantity is 0.200 kg/(m·s), the local heat transfer coefficient is largest. As the diameter decreases, the tube internal heat water temperature increases, the local heat transfer coefficient increases. And the heat transfer coefficient is lager when forced ventilation than natural convection out of the tube. On the sheet, as the spray quantity increases, the tube internal heat water temperature increases, the heat transfer coefficient between the water film and the air increases.And the heat transfer coefficient between the water film and the air is lager when forced ventilation than natural convection out of the tube too.Researched the relations between the heat released by the hot water infinitesimal in the pipe, the heat took out by the water film infinitesimal and the heat dissipation from water film infinitesimal to the air. Indicated that, as the spray quantity increases, the heat released by the hot water infinitesimal in the pipe and the heat took out by the water film infinitesimal increases first and then decreases, and when the spray quantity is 0.200 kg/(m·s), they were largest. As the diameter decreases, the tube internal heat water temperature increases and forced ventilation, the heat released by the hot water infinitesimal in the pipe and the heat took out by the water film infinitesimal increases. As the spray quantity increases, diameter increases, the tube internal heat water temperature increases and forced ventilation, the heat dissipation from water film infinitesimal to the air increases. On the plate, as the spray quantity increases, the tube internal heat water temperature increases and forced ventilation, the average heat dissipation from water film infinitesimal to the air increases.