A systematic approach to the numerical calculation of fundamental quantities of the two-dimensional flow over a circular cylinder

The flow around an infinitely long circular cylinder at Reynolds numbers between 5 <= Re <= 250 is investigated numerically by means of a spectral element method. Careful studies of the effect of resolution and extension of the computational domain on drag and lift forces, base-pressure coefficient and Strouhal number are performed in the laminar, two-dimensional regime. Asymptotic results are obtained by increasing the size of the computational domain to several thousands of cylinder diameters. It is shown that, in contrast to the Strouhal number, the force coefficients and the base-pressure coefficient are strongly dependent on the resolution and even more on the size of the computational domain. For both the asymptotic and finite domains, the Reynolds number relationships are compared to numerical and experimental data from the literature. The results accurately reproduce experimental findings and explain deviations of former numerical investigations. Our database is useful both for validation of numerical codes and measurement verifications where the separation of physical features and effects of experimental arrangements are frequently an open question. (C) 2006 Elsevier Ltd. All rights reserved.