Document Type





spheres, sedimentation, sediments, equations of motion, stokes law, symmetry, particle size, numerical solution, multipoles, series expansion, viscosity, fluids


Chemical Engineering


Exact periodic solutions are found for the relative motion of three spheres sedimenting in a Stokes fluid. Nearby solutions are found to be nearly periodic for a long time. Existence of the exact periodic solutions is proved using the point-particle approximation and symmetry properties of Stokes equations. Numerical simulations for finitie-sized particles are performed using a method of multipole expansions.

Additional Information

Copyright 1988 Physics of Fluids. This article may be downloaded for personal use only. Any other use requires prior permission of the author and Physics of Fluids. The article may be found at

Creative Commons License

Creative Commons Attribution 3.0 License
This work is licensed under a Creative Commons Attribution 3.0 License.



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