Adiabatic absorption and desorption for improvement of temperature-boosting absorption heat pumps

Journal Article · Fri Jan 01 04:00:00 EST 1982 · ASHRAE Trans.; (United States)

OSTI ID:5487634

Grossman, G

This paper is concerned with an improvement in the conventional absorption heat pump cycle that allows for achieving an increased temperature boost and a better coefficient of performance (COP). The improvement is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system, respectively. The adiabatic processes make it possible to obtain the highest possible temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it. This, in turn, allows for efficient utilization of the thermodynamic availability of the heat supply stream. Compared to the conventional cycle, the improved system can operate with a larger difference between the high and low concentrations, less circulation losses, and a more efficient heat exchange. The concept of adiabatic absorption and desorption is described and compared for the conventional and improved cycles. Mathematical expressions are derived for the conditions at the adiabatic points, and design considerations are described for incorporating the improvements in a conventional system. Computer-generated performance curves of COP versus temperature boost are given for the heat pump to illustrate the performance enhancement by the adiabatic process.

• Research Organization: Oak Ridge National Laboratory, Oak Ridge, TN
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5487634
• Journal Information: ASHRAE Trans.; (United States), Journal Name: ASHRAE Trans.; (United States) Vol. 8:2; ISSN ASHTA
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320100* -- Energy Conservation
Consumption
& Utilization-- Buildings
ABSORPTION
ADIABATIC PROCESSES
CHEMICAL HEAT PUMPS
COEFFICIENT OF PERFORMANCE
COMPARATIVE EVALUATIONS
DESORPTION
EFFICIENCY
ENERGY TRANSFER
HEAT PUMPS
HEAT TRANSFER
MATHEMATICAL MODELS
OPTIMIZATION
PERFORMANCE
TEMPERATURE DEPENDENCE
THERMAL EFFICIENCY