Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
655763 | International Journal of Heat and Fluid Flow | 2010 | 12 Pages |
Abstract
At Re = 100, the flow is always steady. The near-wake projected streamline patterns and pressure coefficient contours are topologically similar at α = 0 independent of the range of Ωâ considered. As α increases, the near-wake recirculation bubble is either suppressed or shifted and thus affects the pressure recovery behind the sphere. This in turn affects both the drag and lift coefficients, CD and CL. For all Ωâ considered, CD and CL increase as α increases and the increment is more pronounced at higher Ωâ. At Re = 250 and 300, calculations show both steady and unsteady wake structures. The state of the wake structures depends strongly on α and Ωâ. However, the time-averaged flow fields are qualitatively similar to Re = 100. As a result, the time averaged drag and lift coefficients, CD¯ and CL¯ follow the same trend as at Re = 100. The increase in Re dramatically reduce the CD¯ compared to the same Ωâ and α at Re = 100. CL¯ shows a more complicated behaviour as Re increases.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Fluid Flow and Transfer Processes
Authors
Eric K.W. Poon, Andrew S.H. Ooi, Matteo Giacobello, Raymond C.Z. Cohen,