Analysis of Three-Dimensional Unsteady Viscous Flow around Oscillating Wings

A method based on the Navier-Stokes equations was applied for analyzing the three-dimensional unsteady flow around oscillating wings. These equations were treated in the complete three-dimensional form considering also the irregular geometry of the wing. The vorticity transport equations were discretized using three-dimensional finite elements from a variational formulation and integrated numerically. At each time step of the numerical integration, the velocity field was determined from a representation of the three-dimensional wing by a system of optimized distribution of discrete vortices superimposed on the flow space. The time-dependent boundary conditions on the oscillating wing were specified as external constraint conditions at each step of the numerical integration. Examples of obtained results describing the three-dimensional unsteady flow around a wing were presented.