, Volume 47, Issue 8, pp 1903–1912 | Cite as

A general formula for the drag on a sphere placed in a creeping unsteady micropolar fluid flow

  • E. A. Ashmawy


In the present work, we investigate the creeping unsteady motion of an infinite micropolar fluid flow past a fixed sphere. The technique of Laplace transform is used. The drag formula is obtained in the physical domain analytically by using the complex inversion formula of the Laplace transform. The well known formula of Basset for the drag on a sphere placed in an unsteady viscous fluid flow and that of Ramkissoon and Majumdar for steady motion in the case of micropolar fluids are recovered as special cases. The obtained formula is employed to calculate the drag force for some micropolar fluid flows. Numerical results are obtained and represented graphically.


Drag force Micropolar fluid Unsteady motion Laplace transform 


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of Mathematics, Faculty of ScienceAlexandria UniversityAlexandriaEgypt

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