In this paper a semi-implicit method for three-dimensional circulation in isopycnal co-ordinates is derived and discussed. It is assumed that the ยฏow is hydrostatic and characterized by isopycnal surfaces which can be represented by explicit, single-valued functions. The hydrostatic pressure is dete
Numerical Simulation of Separation Factor of NaCl in Surface Force Pore Flow Model
โ Scribed by B. Sen Gupta; M. A. Hashim
- Publisher
- John Wiley and Sons
- Year
- 2006
- Tongue
- English
- Weight
- 86 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0930-7516
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โฆ Synopsis
Abstract
The surface force poreโflow (SFPF) model is based on soluteโmembrane material interactions at the membraneโsolution interface. It has been used to model the transport of solute and solvent through membranes under the influence of such forces and to determine the separation efficiency based on the assumption of circular pores. It is evident from the model that the pore diameter has a strong bearing upon the separation factor and the mean separation factor can be determined from the pore size distribution. In this work, the mean separation factor (f~mean~) of a cellulose acetate membrane based on the SFPF model has been determined by the Monte Carlo simulation technique. The value of f~mean~ was calculated by averaging the separation efficiency of 100โ000 pores, generated at random from a Gaussian distribution. The results have been compared with the experimental reverse osmosis data for a NaCl/cellulose acetate/water system. The Monte Carlo technique is an improvement over the numerical integration scheme reported in the literature, as it considers the collective effect of all pore sizes and is not restricted by the upper and lower boundaries of numerical integration.
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