Experimental Transient Performance of a Heat Pump Equipped With a Distillation Column.
Experimental Transient Performance of a Heat Pump
Equipped With a Distillation Column.
(291 K)
Gebbie, J. G.; Jensen, M. K.; Domanski, P. A.
International Journal of Refrigeration, Vol. 30, No. 3,
499-505, May 2007.
Keywords:
heat pumps; experiments; refrigerants; binary mixture;
transient; distillation
Abstract:
A series of experiments were conducted on a heat pump
equipped with a distillation column. The system was
operated with R32 and with a 30/70% by mass mixture of
R32/134a to examine the difference between the transient
performance trends with a pure fluid (R32), and those
with a zeotropic mixture (R32/134a). Additionally, the
effects of varying heat transfer fluid mass flow,
compressor speed, and accumulator sump heat input were
examined. Each test was 1 h in duration. The heat pump
capacities did not generally achieve steady state during
the R32/134a tests. Steady state was generally achieved
during the R32 tests. As a percentage of the final
(end-of-test) capacity, the rate of capacity increase
was greater during the R32/134a tests than during those
conducted with the pure fluid. The R32/134a tests
exhibited capacity oscillations early in each transient
that were not present during the R32 tests. The results
show that circulating refrigerant mass and composition
are the primary controlling factors with regard to
transient capacity.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899