Application of HFCs as Refrigerants.
Application of HFCs as Refrigerants.
(2051 K)
Didion, D. A.
International Congress of Refrigeration, 20th
Proceedings. September 19-24, 1999, Sydney, Australia,
[pages unknown] pp, 1999.
Keywords:
refrigerants; hydrofluorocarbons; azeotropic; toxicity;
zeotropic; flammability
Abstract:
The technical criteria for using hydrofluorocarbons
(HFCs), as refrigerants in the vapor compression cycle,
is presented. If thermodynamic performance is to be
optimized, particular attention must be paid to the
fluid's critical point and molar heat capacity. A
reasonable balance between volumetric capacity, which
implies equipment size, and coefficient of performance
is best achieved by selecting a refrigerant of
appropriate vapor pressure. To achieve these balances
for the many different applications, both azeotropic and
zeotropic mixtures of HFCs are now in use. The
characteristics and performance advantages and
disadvantages of these mixtures are discussed.
Additional physical properties of these refrigerants
dealing with lubricant compatibility and safety
considerations, i.e. toxicity and flammability, also are
discussed.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899