# Cylinder flow

Impulsively started flow around a circle at Reynolds number Re =
9500. The solution has been forced to symmetricity by the
numerical method since very small perturbations otherwise yield an
unsymmetric solution. By the random nature of the method used,
such perturbations can never be completely avoided.

#### References

The numerical method employed in the simulations was described
in *P. Deglaire, S. Engblom, O. Ågren, H. Bernhoff:
Analytical solutions for a single blade in vertical axis turbine
motion in two-dimensions*, in *Eur. J. Mech. B Fluids*
28(4):506--520,
2009: (doi).
The fast multipole method was further detailed
in *S. Engblom: On well-separated sets and fast multipole
methods*, in *Appl. Numer. Math.* 61(10):1096--1102,
2011: (doi).

Stefan Engblom
Last modified: Thu May 10 11:04:19 MEST 2013