Analysis of a falling film H2O/LiBr absorber at local scale based on entropy generation

A solution of laminar H2O/LiBr falling film flowing under the effect gravity on a vertical plate heated by heat transfer fluid was studied to determine local temperature, concentration and velocity fields from numerical resolution. In order investigate real absorber case, assumed flow counter-current film. Different regimes were compared with limit cases: adiabatic isothermal walls. entropy generation formulation performed identify different sources irreversibility aim locating quantifying them. The results enabled analysis distribution in entire absorber, namely, fluid, wall shows that an increase driving force generated at interface leads absorbed mass rate, but this is associated higher irreversibility. Thermal dominates near for both fluids while interface. Total per width mainly due irreversibilities through – more than 35% represent less 15% assumptions considered.