Numerical Simulation and Experimental Studies on Falling Film Outside Elliptical Tube(I):CFD Simulation

In this paper,theoretical analysis and Computational Fluid Dynamics(CFD) study on falling film process of elliptical tubes for seawater desalination was conducted.And the results were also compared with that of the round pipes.A 3-D numerical simulation of falling film flow is made using FLUENT software which has been further exploited with user defined functions(UFD),the mathematical model was established by distributed-parameter method.The simulation results show that the effect of the sectional shapes of elliptical tubes on falling film flow is obviously,the E=1.5 elliptical tube surface is relatively easy to form columnar flow,with the good uniformity characteristics of thin liquid film.When the inlet velocity is 0.8 m/s,the state of liquid distribution outside the elliptical tube is the best.