The Effect of Permeability on the Drag of a Porous Sphere in a Uniform Stream
- 1 January 1971
- journal article
- research article
- Published by Wiley in ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik
- Vol. 51 (1) , 27-32
- https://doi.org/10.1002/zamm.19710510103
Abstract
The present investigation is concerned with the problem of studying the effect of permeability on drag coefficient for the flow past a porous sphere placed in an otherwise uniform incident stream at low Reynolds number. The problem is formulated using the full Navier‐Stokes equations describing the flow outside the sphere while Darcy's law governs the flow inside the sphere. The solution is, then, sought by the method of matched asymptotic expansions involving three simultaneous expansions up to an order Re. It is found that the effect of porosity on the drag is that it reduces the effective radius a of the sphere by a factor (1 + k'/2a2)−1, where k' is the permeability.Keywords
This publication has 3 references indexed in Scilit:
- Two Generalizations of the Stokes Formula for a Porous SphereZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, 1966
- The Effect of Permeability on the Slow Motion of a Porous Sphere in a Viscous LiquidZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, 1964
- Expansions at small Reynolds numbers for the flow past a sphere and a circular cylinderJournal of Fluid Mechanics, 1957