Performance Enhancement of Direct Evaporative Cooling System using Cold Water Energy Storage Reservoir

In this investigation, performance enhancement of direct evaporative cooling system using storage reservoir of cold water has been studied. The water in the reservoir is aimed to store the cold energy overnight and use it during daytime to reduce the temperature of exhaust air from cooler. In this paper, at first stage, the governing equation of above mentioned hybrid direct evaporative cooler is extracted and then, the effect of water storage reservoir mass on the temperature of exhaust air from cooler is investigated. Take a typical summer day in Tehran for example; the results indicate that the use of storage reservoir containing water with a mass of three times larger than the mass of dry air passed through cooler per hour decreases the temperature of the cooled air by 2.02℃ at 14:00 clock. The major advantages of this system are shifting the hours for the maximum and minimum cooled air temperatures towards other hours of a day (e.g., from 05:00 and 14:00 to 06:00 and 18:00, respectively) as well as reducing the cooled air temperature range from 6 to 3.5℃.