Experimental and analytical study on falling film absorption in smooth and chute low‐ribbed tubes

A mathematical model was applied to falling film absorption outside the smooth and chute low-ribbed tubes to analyze the heat and mass transfer in the absorber. The liquid film outside tubes was assumed to consist of two layers, i.e., internal and external layers. A numerical calculation method was used to solve for the outer layer model of smooth tubes and the chute low-ribbed tubes. An analytical method was employed to solve for the velocity, temperature, and concentration in the internal layer of the tubes mentioned above. A second-order coupling method was adopted to couple the results of the two layers. It was shown that the agreement between the calculation results and the experimental data is high, with all errors assessed at less than 10%. The causes leading to the errors were analyzed. It was concluded that the chute low-ribbed tubes could serve as intensification tubes suitable for use in the absorber of lithium bromide absorption. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(1): 29–39, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20039