Heat and Mass Transfer Enhancement for Falling Film Absorption Process in Vertical Plate Absorber by Adding Copper Nanoparticles

This paper examined the effect of nanoparticles on the absorption of vapor into a liquid film of lithium bromide aqueous solution flowing down over a cooled vertical channel. For this, we realized a two-dimensional code which solves the governing equations using Comsol Multiphysics. In this model, the cooling water flows countercurrent to a solution of concentrated lithium bromide mixed with the copper nanoparticles. After the validation of the model, the effects of parameters such as Reynolds number, solid volume fraction of copper nanoparticles, inlet concentration and inlet temperature of solution on the performance of the absorption are presented and discussed. The important results indicate that the mass and heat transfer in binary nanofluids are enhanced more than that in base fluid and the efficiency of the nanofluid becomes higher to that of the base fluid for a lower Reynolds number and the inlet concentration and for a higher inlet temperature of solution.