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Minimizing Throttline Losses in the Refrigeration Cycle.

pdf icon Minimizing Throttline Losses in the Refrigeration Cycle. (4245 K)
Domanski, P. A.

International Congress of Refrigeration, 19th Proceedings. Volume IVb. Theme 4. IIR Commission B2. August 1995, Hague, The Netherlands, 766-773 pp, 1995.


refrigeration; air conditioning; economizer; ejector; liquid-line/suction-line heat exchanger; Rankine cycle; vapor compression cycle


Most alternative non-CFC refrigerants have a large molecular structure and large heat capacity, which influence the slope of saturated liquid line and result in substantial throttling losses in a basic reversed Rankine cycle. These losses degrade the cycle efficiency below that of the original CFC fluids; virtually all carbon-based non-hydrocarbon refrigerants have a lower Coefficient of Performance than the fluids banned by the Montreal Protocol. This study analyzes the performance of pure-component refrigerants in the basic refrigeration (reversed Rankine) cycle and in three modified cycles in which the throttling-process irreversibilities are minimized: the liquid-line/suction-line heat exchange (llsl-hx) cycle, the economizer cycle, and the ejector cycle. The refrigerants considered in this study were the 38 fluids covered by REFPROP /1/, and REFROP property routines were employed in performance simulations. The Carnahan-Starling-DeSantis equation of state was applied for all fluids except ammonia, for which a formulation by Harr and Gallagher was used.