Abstract An implicitly coupled elliptic numerical model is applied to study the two-phase falling film absorption inside a parallel plate vertical channel. A complete set of two-phase two-dimensional governing equations are solved for co-current laminar flows of LiBr solution and water vapour. A precise liquid-gas interface is determined dynamically during solution over a non-orthogonal structured moving mesh. Fundamental interface boundary conditions are implemented to model the heat and mass interchange between the two phases. The capability of this new model is demonstrated through detailed comparisons with two previous parabolic and elliptic models. The impacts of the interface heat of absorption and mass fraction condition and the liquid film diffusion coefficient are investigated. New results are presented to examine the channel inlet pressure effect on the liquid film thickness development over the cold wall and the heat and mass transfer at the interface.

中文翻译：

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垂直平行板通道中降膜吸收水蒸气的椭圆数值分析

摘要 应用隐式耦合椭圆数值模型研究平行板垂直通道内的两相降膜吸收。针对溴化锂溶液和水蒸气的并流层流，求解了一套完整的两相二维控制方程。在非正交结构移动网格上的求解过程中动态确定精确的液-气界面。实施基本界面边界条件来模拟两相之间的热量和质量交换。通过与之前的两个抛物线和椭圆模型进行详细比较，证明了这种新模型的能力。研究了界面吸收热和质量分数条件以及液膜扩散系数的影响。