Experimental study on enhancement of falling film absorption process by adding various nanoparticles

Absorption air conditioning system containing no chlorofluorocarbons is considered environmentally friendly and a competitive alternative to conventional vapor compression air conditioning system. One of the most commonly used refrigeration working pair is LiBr/H2O. This paper experimentally studies the falling film absorption of LiBr/H2O with various kinds of nanoparticles dispersed, such as Cu, Al2O3 and CNT. The results show that the variety, mass fraction and size of nanoparticles, as well as solution flow rate are considered as the key parameters. The smaller the nanoparticles size, the better the effective absorption ratio. The larger the nanoparticles mass fraction, the better the effective absorption ratio. The best enhancement is achieved by adding Cu nanoparticles for all the studied nanoparticles species. The effective absorption ratios for all the studied cases are higher than 1.0, which proves that the dispersed nanoparticles have positive effects on the absorption process.