在溴化锂吸收式制冷系统中，吸收器的换热性能在很大程度上影响着整个机组的制冷性能，故研究如何提高吸收器的性能很有必要。本文在理论分析光滑横管外降膜吸收传热特性的基础上，对管外缠绕不同丝径金属丝网的强化管进行理论分析与数值模拟。研究结果表明：随着周向角的增加，换热管表面液膜厚度先减小后增大，热边界层厚度逐渐增大，局部传热系数逐渐减小；光滑横管外包敷金属丝网后，吸收器的换热性能大大提高，但丝径过小或过大都会影响换热效果；当强化管丝径为0．2mm 时，最有利于吸收器换热。%In the Lithium Bromide(LiBr)absorption refrigeration system,the heat transfer per-formance of the absorber largely influences the heat transfer performance of the entire refrigera-tion system,so it is necessary to explore how to improve the absorption effect of the absorber. Based on the analysis of heat transfer properties in falling-film absorption outside the smooth tubes,the theoretical analysis and numerical simulation are carried out about the heat transfer en-hanced tubes wrapped with a stainless-steel wire-mesh screen to hold up more liquid film in this paper.The research results show that with an increase of the radius angle,the liquid film thick-ness decreases first and then increases with the thermal boundary layer thickness increasing and the local heat transfer coefficient decreasing.The measurement of wrapping the horizontal tube with a wire-mesh screen can enhance the heat and mass transfer performance in absorber.But if the wire diameter is too big or too small,it will has a bad influence on the heat and mass transfer performance.When the wire diameter is equaling to 0.2mm,the heat transfer performance and the absorption effect are the best.
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