ASYMPTOTIC METHOD FOR DETERMINING ENERGY DISSIPATION AND DRAG COEFFICIENT IN A PERIODIC FLUID FLOW AROUND PLATES

A periodic flow of an incompressible fluid around plates at high Reynolds numbers and low Keulegan–Carpenter numbers is considered. Energy dissipation per oscillation period and drag coefficient of plates are determined. The two-dimensional problems under study are a problem of translational and angular oscillations of a flat plate and a plate shaped as a circular arc, a problem of translational oscillations of a circular cylinder with symmetrically located edges, a problem of angular oscillations of cruciform plates, and a problem of a periodic flow around an inclined edge on a flat wall. Also, a three-dimensional problem of translational and angular oscillations of a thin circular disk is considered. All the resulting dependences for energy dissipation and drag coefficient are presented in analytical form via velocity intensity factors, which characterize the velocity singularity at the sharp edges of the plates with a potential flow around an ideal fluid. Some of the resulting dependences are compared with the available numerical and experimental data.