Water Vapor Absorption Enhancement in LiBr/H2O Films Falling on Horizontal Tubes

An experimental investigation was conducted into the enhancement of water vapor absorption in aqueous lithium bromide solution films falling on horizontal tubes. The variable parameters included the solution flow rate, the inlet temperature of the cooling media, the solution inlet temperature and the effective extended surfaces. The experimental results, which were correlated with the film Reynolds number, showed that the cooling by the tube wall was the governing factor in the absorption process for small solution flow rates, but the inlet subcooling of the solution dominated the absorption performance for large flow rates. Also, the R tube, which has a unique ridged fin shape, exhibited the best absorption performance among the tested tubes.