Heat transfer additives for absorption cooling system fluids. Final report, October 1989-March 1993

Technical Report · Mon Mar 01 04:00:00 EST 1993

OSTI ID:6200142

Wood, B D; Berman, N S; Kim, K; Chau, D S.C.

The work was directed towards developing a quantitative understanding of the phenomena that can enhance the heat and mass transfer in the absorber of an absorption chiller. Emphasis during the first year of a 3 year study was placed on compiling a comprehensive property data base and doing some exploratory experiments. During the second year experimental methods associated with heat and mass transfer in a falling film absorber were emphasized. All experiments used 2-ethyl-1-hexanal as the additive (surfactant) in an aqueous LiBr solution. The mass and heat transfer coefficients were found using the log mean averages based on the inlet and outlet properties. Significant accomplishments include: the onset of enhanced transfer was in the 2 to 200 ppm additive concentration range of surfactant and when 30 ppm was reached in the experiments the maximum enhancement was achieved. From 30 to 200 ppm additive concentration the enhancement remained the same. Visual observations of the experiments using the long absorber (85 cm) showed that chaotic flow was occurring only over the first half of the absorber. The majority of the tests were done with 100 ppm solutions of the surfactant. Tests as a function of absorber length showed that the mass transfer for 60% solution was about a factor of two. Tests on 50% LiBr showed an increase of a factor of 5.7 over the first 40 cm of length.

• Research Organization: Arizona State Univ., Tempe, AZ (United States). Center for Energy Systems Research
• OSTI ID: 6200142
• Report Number(s): PB-93-202521/XAB; CNN: GRI-5089-260-1874
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
ABSORPTION REFRIGERATION CYCLE
ADDITIVES
ALKALI METAL COMPOUNDS
AMMONIA
BROMIDES
BROMINE COMPOUNDS
COOLING
COOLING SYSTEMS
DATA
DIMENSIONS
DISPERSIONS
ENERGY SYSTEMS
ENERGY TRANSFER
FLUIDS
HALIDES
HALOGEN COMPOUNDS
HEAT TRANSFER
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
LENGTH
LITHIUM BROMIDES
LITHIUM COMPOUNDS
LITHIUM HALIDES
MASS TRANSFER
MIXTURES
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NUMERICAL DATA
QUANTIZATION
RESEARCH PROGRAMS
SOLUTIONS
STATISTICAL DATA
SURFACTANTS
WORKING FLUIDS