Abstract: | A local domain-free discretization-immersed boundary method (DFD-IBM)
is presented in this paper to solve incompressible Navier-Stokes equations
in the primitive variable form. Like the conventional immersed boundary method
(IBM), the local DFD-IBM solves the governing equations in the whole domain including
exterior and interior of the immersed object. The effect of immersed boundary
to the surrounding fluids is through the evaluation of velocity at interior and
exterior dependent points. To be specific, the velocity at interior dependent points
is computed by approximate forms of solution and the velocity at exterior dependent
points is set to the wall velocity. As compared to the conventional IBM, the
present approach accurately implements the non-slip boundary condition. As a result,
there is no flow penetration, which is often appeared in the conventional IBM
results. The present approach is validated by its application to simulate incompressible
viscous flows around a circular cylinder. The obtained numerical results
agree very well with the data in the literature. |