TY - GEN
T1 - Thermal conductivity enhancement of binary nonoemulsion(O/S)
AU - Sul, Hea Youn
AU - Jung, Jung Yeul
AU - Kang, Yong Tae
PY - 2010
Y1 - 2010
N2 - Binary nanoemulsions, nano-sized oil-droplet suspensions in binary solution (H2O/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel four-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. To stabilize the nanoemulsions in a strong electrolyte, a polymeric stabilizer (Gum Arabic) is used as a steric stabilizer. The droplet size and the thermal conductivity of binary nanoemulsions are measured by the dynamic light scattering method and the transient hot-wire method, respectively. It is concluded that the ratio of 2:1 (oil: surfactant) is the best condition for distribution stability. It is also found that the measured thermal conductivity of the oil-in-water nanoemulsion enhances up to 6.4 % at 0.1 vol% of oil, and the binary nanoemulsion enhances up to 3.6 % at 1.0 vol % of oil in 30 wt % H2O/LiBr compared with the estimated one from the Maxwell's model. This result is compared with electric conductivity of LiBr solution and it is found both conductivities have similar trend. It is finally proposed that the thermal conductivity of the binary nanoemulsion could be enhanced by adding nano-sized droplets of n-decane oil, which has a lower thermal conductivity than that of the base fluid.
AB - Binary nanoemulsions, nano-sized oil-droplet suspensions in binary solution (H2O/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel four-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. To stabilize the nanoemulsions in a strong electrolyte, a polymeric stabilizer (Gum Arabic) is used as a steric stabilizer. The droplet size and the thermal conductivity of binary nanoemulsions are measured by the dynamic light scattering method and the transient hot-wire method, respectively. It is concluded that the ratio of 2:1 (oil: surfactant) is the best condition for distribution stability. It is also found that the measured thermal conductivity of the oil-in-water nanoemulsion enhances up to 6.4 % at 0.1 vol% of oil, and the binary nanoemulsion enhances up to 3.6 % at 1.0 vol % of oil in 30 wt % H2O/LiBr compared with the estimated one from the Maxwell's model. This result is compared with electric conductivity of LiBr solution and it is found both conductivities have similar trend. It is finally proposed that the thermal conductivity of the binary nanoemulsion could be enhanced by adding nano-sized droplets of n-decane oil, which has a lower thermal conductivity than that of the base fluid.
KW - Absorption system
KW - Electric conductivity
KW - Emulsion
KW - Stability
KW - Thermal conductivity
KW - Water-lithium bromide
UR - http://www.scopus.com/inward/record.url?scp=84860502280&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84860502280&partnerID=8YFLogxK
U2 - 10.1115/IHTC14-22556
DO - 10.1115/IHTC14-22556
M3 - Conference contribution
AN - SCOPUS:84860502280
SN - 9780791849415
T3 - 2010 14th International Heat Transfer Conference, IHTC 14
SP - 625
EP - 630
BT - 2010 14th International Heat Transfer Conference, IHTC 14
T2 - 2010 14th International Heat Transfer Conference, IHTC 14
Y2 - 8 August 2010 through 13 August 2010
ER -