Limiting Throttling Losses by Intracycle Evaporative Cooling.
Limiting Throttling Losses by Intracycle Evaporative
Cooling.
(419 K)
Kim, B. S.; Domanski, P. A.
KSME-JSME Thermal Engineering, Third (3rd) Conference.
Volume 3. October 20-23, 1996, Kyongju, Korea, 451-462
pp, 1996.
Sponsor:
Department of Energy, Washington, DC
Keywords:
cooling; evaporative cooling; simulation; test
facilities; refrigeration
Abstract:
The temperature glide of zeotropic mixtures during phase
change provides the opportunity to limit throttling
losses of the refrigerant leaving the condenser. The
difference between the intracycle evaporative cooling
and the liquid-line/suction-line heat exchanger, instead
of superheated vapor, is that a two-phase low-pressure
refrigerant is used to subcool the high-pressure liquid
leaving the condenser. The merits of the intracycle
evaporative cooling were evaluated by a semi-theoretical
simulation model and in the NIST's Small Breadboard Heat
Pump at the cooling mode operating condition typical for
a water-to-water residential heat pump. The capacity,
coefficient of performance (COP), pressures, and
temperature profiles of refrigerant and heat-transfer
fluid in the heat exchangers are reported. The
laboratory measured improvement of the COP was 4.0% for
R32/152a(50/50), 3.6% for R407C, and 1.8% for
R23/152a(20/80).
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899