TY - EJOU
AU - Sousa, J.M.M.
TI - Numerical Simulations of Unstable Flow through a Spherical Bulge in a 90-degree Asymmetrical Bend
T2 - Computer Modeling in Engineering \& Sciences
PY - 2005
VL - 9
IS - 2
SN - 1526-1506
AB - Time-dependent numerical simulations of the flow through a spherical bulge in a 90-degree asymmetrical bend have been performed for Reynolds numbers in the range 100-400. The present results have demonstrated that the flow reaches asymptotically steady, symmetrical solutions for Reynolds numbers up to 300, whereas a value of 400 for this parameter leads to unsteadiness. The computed flow behavior at this higher Reynolds number has shown to be characterized by an intermittent transition between small-amplitude, irregular oscillations and large-amplitude bursts occurring at a low frequency. In addition, the unsteady flow was asymmetrical and exhibited swirl switching.
KW - Unstable flow
KW - symmetry-breaking
KW - intermittency
KW - spherical bulge
KW - asymmetrical bend
DO - 10.3970/cmes.2005.009.211