Predicted Effect Of Flowrate And Cooling Temperature On Horizontal Round Tube Absorber Of A Pair Working Fluid NH3- H2O

Abstract

The performance of the absorption refrigeration system depends much on the absorber. The falling film absorption and bubbleabsorption studies performedexperimentallyand numericallyfor completed absorbers. This paper focuses on evaluating the parameters affecting the coupled heat-mass transfer as NH3-H2O diluted solution flowing on horizontal round tubes absorbsNH3vapor to become the stronger concentratedsolution. The fields ofvelocity, temperature, concentration and thickness of the falling film solution varied by the input conditions of diluted solution and cooling water temperature flowing in the tube represented by a test volume element of thetube.The two-dimensional numerical simulation is written by the Matlab programming language to solve partial differential equations predicting absorption efficiency while changing the parameters affecting the absorption process. Keywords:Absorption process, NH3-H2O solution, falling film on round tube Nomenclature x- Tangential coordinate along solution flow direction (m) y-Local radial coordinate normal to solution flow direction (m) e-Non-dimensional tube half-circumference η- Non-dimensional film thickness u- Circumferential velocity (m/s) v- Normal velocity (m/s) δ- Film thickness (m) ω- Solution concentration T- Temperature (K) αib-Convective heat transfer coefficient from interface to bulk (W/m 2 K) αbw-Convective heat transfer coefficient from bulk to wall (W/m 2