The comparison of numerical calculations and visualizations of the flow of a viscous fluid produced by a cylinder in translation and rotation

Using two separate methods, one numerical and one experimental, it is possible to obtain new information concerning the flow of a viscous fluid around a circular cylinder subjected, after an impulsive start, to a combination of rotation and translation. The numerical method is based on the solution of the unsteady Navier-Stokes equations. The experimental study is carried out by visualization of the quasi-instantaneous velocity fields using solid tracers. A comparison of the experimental and numerical results is given and the network of typical streamlines obtained for a Reynolds number of 500, are presented. It is shown that the visualizations of the corresponding fields, given in parallel, are in good agreement.