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For enhancing the vapour absorption in LiBr solution systems, a novel absorber with tube and mesh packing alternating structure is designed and investigated. Stainless steel mesh screens are folded as the longitudinal trough mesh packing, and inserted to the gaps of horizontal tubes to make the absorbent flow through the tube and mesh packing regimes successively, thus forming an alternating heat and mass transfer absorption process. Experimental investigation is conducted to characterize the absorption performance of the absorption bodies of this alternating structure and conventional horizontal coils. The results show that the average mass transfer rate and cooling load are increased by 17.2% and 6.23% respectively, which confirms that the alternating structures can promote the absorption. The mesh packing provides extended absorption area, slows down the flow and well mingles the solution, which are all beneficial for vapour absorption. [ABSTRACT FROM AUTHOR]

A new alternate absorption scheme of both horizontal tubular cooling absorption and mesh layer adiabatic absorption was investigated with longitudinal corrugated M–W mesh guiders inserted to the gaps of the staggered horizontal tube bundle, leading solution film flows from the lower edge of each tube to the upper edges of its lower position neighbouring tubes at both sides. The mirror symmetric M–W mesh guiders facilitate uniform distribution and dual-side exposing solution film to the vapour for adiabatic mass transfer. The VOF CFD models were established for vapour absorption with aqueous LiBr solution falling film on the alternate absorber and bare tube one. The distributions of liquid film, temperature and concentration of the solution and local heat transfer coefficient on the tube surfaces were demonstrated for both absorbers. The simulation results demonstrated that the average heat and mass transfer coefficients with the alternating absorber are respectively 33.4% and 55.4% higher than those of the bare tube one. [ABSTRACT FROM AUTHOR]