CFD Analysis of Falling Film Hydrodynamics for a Lithium Bromide (LiBr) Solution over a Horizontal Tube

摘要: Falling film evaporators are used in applications where high heat transfer coefficients required for low liquid load and temperature difference. One such application is the lithium bromide (LiBr)-based absorber generator. The concentration of aqueous LiBr solution changes within generator because evaporation vapor absorption. This causes thermophysical properties to differ affects distribution, heat, mass mechanisms. For thermal performance improvement LiBr-based falling evaporators, in-depth analysis at micro level distribution hydrodynamics. In this work, a 2D numerical model was constructed using commercial CFD software Ansys Fluent v18.0. influence corresponding droplet jet mode, concentration, on hydrodynamics examined. It found that mode more stable higher 0.65 with ±0.5% variation compared lower concentrations. recirculation stronger 0.45 existed until angular position (θ) = 10°, whereas it diminished after θ 5°. improved expected concentrations due thickness resistance, recirculation, velocity field.