An experimental investigation of heat transfer enhancement by addition of high-alcohol surfactant (HAS) and dissolving salt additive (DSA) in spray cooling

The effects of addition of high-alcohol surfactant (HAS, i.e. 1-Octanol or 2-ethyl-hexanol) on the heat transfer enhancement of water spray cooling were studied experimentally. For comparison, the heat transfer performances of water spray cooling with dissolving salt additive (DSA, i.e. NaCl or Na2SO4) were tested also. For the addition of 200 ppm 1-Octanol or 150 ppm 2-ethty-hexanol, the heat transfer of spray cooling on the hot surface at about 80 degrees C increased 28% or 36% than that without any additive, while for addition of 1.76% NaCl or 2.76% Na2SO4, the heat transfer performance increased about 29% or 31%. It showed that both HAS and DSA could significantly enhance the heat transfer of water spray cooling at a suitable concentration, and the HAS, especially 2-ethyl-hexanol, showed higher performance in the heat transfer enhancement. (C) 2012 Elsevier Inc. All rights reserved.