Feed Rate on Velocity Field of Liquid Film in a Wiped Film Molecular Distillatory

Abstract:

Effect of feed flow rate on velocity field of evaporating liquid film in a wiped film molecular distillatory was studied with a computational fluid dynamics (CFD) method. Three assumptions were introduced in order to simplify modeling processes. According to our previous study, the RNG k-εturbulent model treating near-wall flow was properly used in this simulation. The volume of fluid (VOF) multiphase model was also applied to track the liquid-gas surface. A near-wall modeling method, enhanced wall treatment, was used to consider the effect of walls. Simulations were carried out in rotating coordinate system. All simulation results are reasonably identical with real situation and were discussed in several aspects. It was concluded that increment of feed flow rate would reduce the turbulence of liquid film on the evaporator surface and then reduce the evaporation rate.

• Periodical: Advanced Materials Research (Volumes 560-561)
• Pages: 46-51
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.560-561.46
• Online since: August 2012
• Authors: Ai Shuang Xiang, Xiao Ming Wang, Song Lin Xu
• Keywords: Feed Flow Rate, Molecular Distillation, Rotating Coordinate System, Velocity Field, Wiped Liquid Film

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