Filter
Top Products
6 TRG-TRC011-EN
notes
period one
Absorption Refrigeration Cycle
Absorption System Fluids
Probably the greater of these differences between the vapor-compression and
absorption refrigeration cycles, however, is the types of fluids used. The vapor-
compression refrigeration cycle generally uses a halocarbon (such as
HCFC-123, HCFC-22, HFC-134a, etc.) as the refrigerant. The particular absorption
refrigeration cycle discussed in this clinic uses distilled water as the
refrigerant.
Distilled water is stable, nontoxic, low in cost, readily available,
environmentally friendly, and has a relatively high heat of vaporization
(1000 Btu/lb [2326 kJ/kg]). The heat of vaporization is the amount of heat
required to fully transform (evaporate) liquid to a vapor at a given pressure.
For the water to be used as a refrigerant, the cycle must operate in a vacuum,
that is, at a pressure below atmospheric pressure. This will be discussed
shortly. Finally, large quantities of water are easily absorbed by the absorbent
and separated within the absorption cycle.
Throughout the remainder of this clinic, when the term refrigerant is used, it
refers to distilled water.
▲
◆ Stable
◆ Nontoxic
◆ Low cost
◆ Readily available
◆ Environmentally friendly
◆ High latent heat of
vaporization
Figure 7