Method of fundamental solutions for partial-slip fibrous filtration flows

• Published in: International journal for numerical methods in fluids 2009-09, Vol.61 (3), p.255-274
• Main Authors: Zhao, Shunliu, Povitsky, Alex
• Format: Article
• Language: English
• Subjects: Accuracy; Applied sciences; Chemical engineering; Computational methods in fluid dynamics; Cylinders; Exact sciences and technology; Fibers; fibrous filtration; Filtration; Fluid dynamics; Fundamental areas of phenomenology (including applications); Liquid-liquid and fluid-solid mechanical separations; Mathematical analysis; Mathematical models; method of fundamental solutions; micro-fluids; partial-slip boundary conditions; Physics; Pressure drop; Stokes flow; Stokeslets; Submerged
• ISSN: 0271-2091; 1097-0363; 1097-0363
• DOI: 10.1002/fld.1955

In this study a Stokeslet‐based method of fundamental solutions (MFS) for two‐dimensional low Reynolds number partial‐slip flows has been developed. First, the flow past an infinitely long cylinder is selected as a benchmark. The numerical accuracy is investigated in terms of the location and the number of the Stokeslets. The benchmark study shows that the numerical accuracy increases when the Stokeslets are submerged deeper beneath the cylinder surface, as long as the formed linear system remains numerically solvable. The maximum submergence depth increases with the decrease in the number of Stokeslets. As a result, the numerical accuracy does not deteriorate with the dramatic decrease in the number of Stokeslets. A relatively small number of Stokeslets with a substantial submergence depth is thus chosen for modeling fibrous filtration flows. The developed methodology is further examined by application to Taylor–Couette flows. A good agreement between the numerical and analytical results is observed for no‐slip and partial‐slip boundary conditions. Next, the flow about a representative set of infinitely long cylindrical fibers confined between two planar walls is considered to represent the fibrous filter flow. The obtained flowfield and pressure drop agree very well with the experimental data for this setup of fibers. The developed MFS with submerged Stokeslets is then applied to partial‐slip flows about fibers to investigate the slip effect at fiber–fluid interface on the pressure drop. The numerical results compare qualitatively with the analytical solution available for the limit case of infinite number of fibers. Copyright © 2008 John Wiley & Sons, Ltd.