OSCILLATING FLOWS IN COMPLEX GEOMETRIES

In the present book, two unsteady fluid flows are considered. Both
flows are characterized by a complex geometry and are investigated by
numerical means using the same approach.
The adopted numerical approach couples a standard fractional step
method (Verzicco & Orlandi [1]), to solve the governing equations in
the time and space domain, with an immersed boundary technique (Fadlun
et al. [2]) to force the no-slip condition at the solid boundaries. A
Cartesian coordinate system is introduced along with a regular numerical
grid. Spatial derivatives are approximated by means of second order
finite differences while a 3rd order Runge-Kutta scheme is employed to
advance in time. The adopted numerical algorithm allows to consider
flow fields in a complex geometry with affordable numerical efforts.