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Extensive laboratory experiments were carried out to investigate the uniform-shear flow approaching a circular cylinder. The aim was to present the Strouhal number (St)-Reynolds number (Re) diagrams over a broad range of the shear parameter K (0 < K < 0.25) and at higher values of Re (600 < Re < 1600). An image processing technique, in conjunction with flow visualization studies, was used to secure more quantitative depictions of vortex shedding from the cylinder. The Strouhal number increases with increasing shear parameter. The drag coefficient decreases with increasing Re; also, C d decreases as the shear parameter K increases.

Investigations have been made of three-dimensional flows of an incompressible viscous fluid in a square cubic cavity. The flows are driven by the sliding upper surface of the cavity. Numerical solutions are obtained by directly integrating the full, three-dimensional, time-dependent Navier-Stokes equations. The three-dimensional flow structure is examined in detail over a wide range of the Reynolds number Re. One primary finding of these three-dimensional numerical simulations indicates that steady solutions are attained at lower values of Re, but the flow becomes unsteady at higher values, say, when Re exceeds approximately 2000. Due to the profound influence of the endwall effects, three-dimensional flows show substantial differences from two-dimensional solutions: for two-dimensional flow situations, steady solutions are known to exist for up to Re ~10000. The three-dimensional flow structure displays qualitatively distinct features in the low-Re and high-Re regimes. The demarcation separating these two regimes appears to lie in the neighborhood of Re = 2000-3000. One principal characteristic is that the Taylor-Gortler-hkc vortices are discernible for the high-Re regimes, although these have not been clearly captured in the numerical results for the low-Re regimes. Critical assessments of the present numerical results have been made by cross-checking the data with the available experimental measurements for three-dimensional cavity flows. The comparisons demonstrate broad qualitative agreement between the present numerical computational results and the laboratory measurement data.