Convegni ATI - Accesso riservato soci CTI

Autore: J.A. Manrique

Collana: CA - 61 - Perugia 2006

Note:
The conservation and efficient use of energy has led to alternate methods for air conditioning in buildings. Presently, two types of absorption air-conditioning systems are widely used: the lithium bromide-water system and the water-ammonia system. The first type might be a water fired absorption chiller while the second one is a gas fired chiller. A single-effect indirect-fired air-cooled water-ammonia system requires higher operating temperatures in the generator than the lithium bromide-water system, but its output can be at a temperature well below 0 °C, making this type of units very attractive in some refrigeration applications. One additional advantage of this system is that it does not require a cooling tower. This is an important feature in some places where water is scarce or of poor quality. On the other hand, air cooling requires higher heat rejection temperatures. The aim of the present work was to modify a 3 ton commercially available gas-fired water-ammonia absorption chiller in order to operate it with solar energy. The generator and rectifier were designed to work with a stream of hot water supplied by an array of evacuated heat pipes. This paper is primarily concerned with the theoretical model used in the analysis of the absorption cycle as well as with the experimental results obtained with a prototype.