Thermosyphon cooling
Air conditioning system using fan coils, induction units or chilled ceilings require the chilled water throughout the year. As an alternative operating system compression vapor in the traditional manner, in winter, you can switch the compressor is switched off and rely on the natural circulation of the refrigerant between the evaporator and the condenser, under favorable conditions, performance while one of the forms of a heat pipe. Cm. Fig. 9.9. Capacitor is located above the evaporator and the compressor and expansion valve temporarily passed by. Water is cooled in the evaporator causes liquid refrigerant evaporates and migrate up into the condenser under pressure difference corresponding to the higher temperature in the evaporator (chiller) and lower temperature in the refrigerator.
Steam condenses on the cold airflow or watercourse on the outer surface of heat exchange, the condenser and the liquid refrigerant flows by gravity back to the evaporator. Three ports, two-valve position on the A and b must be converted to the appropriate positions.
Thermosyphon cooling was first developed in 1984, according to Pearson (1990) and Blackhurst (1999), and has been successfully used with conventional refrigerants. Since 1997 he has also been applied for use with ammonia as a refrigerant, great attention is paid to safety, in accordance with BS 4434, 1989.
Pierson (1998) notes that the heat exchange on the surface cupro-Nickel tubes can be enhanced by providing coverage that increases the number of nucleation sites on the surface. He argued that the thermal conductivity can be increased more than three. When properly designed, installed and put into operation, having cooling provides a very effective way of operation of the refrigeration, air-conditioning systems. The compressor does not start when the local weather conditions allow the free cooling and transition through the compressor for free cooling can be automatic...
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Air-Conditioning 