Research for Air Cooling System Using Vacuum-Cooled Water Refrigerant

Abstract

An air-cooling system of a small capacity of several kilowatts using only water refrigerant as a non-CFCs (Chlorofluorocarbon) technology is examined. The experimental device consists of two stages. The first stage is composed of a vacuum pump and a vacuum chamber of about 60 L in volume. The second stage has two heat exchangers (the exchanger located outside the vacuum chamber is a dummy cooling load) and a water circulating pump. An air-conditioner indoor unit or a heater is used as a dummy cooling load. The temperature and humidity characteristics are measured at each place. Consequently, the ability to cool the room air is ensured by an air-cooling system using only water refrigerant. A new vacuum pump, that can exhaust a large amount of water vapor, is developed and its properties are measured. It seems that the engine-based vacuum pump performance is sufficient to drive the air cooling system with water refrigerant.