In this paper, the recent developed Local Domain Free Discretization method combined with Immersed Boundary Method (called LDFD-IBM) is extended from two-dimensional version to three-dimensional version. LDFD-IBM is a new member in the family of Cartesian mesh methods. The advantages of LDFD-IBM over other Cartesian mesh solvers includes: no cutting cell, easy to adaptive mesh refinement, easy to implement for moving boundary problems, truly second order accuracy over whole domain, no flow penetration into the solid wall.
LDFD-IBM three-dimensional solver is then used to simulate three-dimensional flow past a circular cylinder. Both oblique mode and parallel mode of vortex shedding of the cylinder in three-dimensional configuration are reproduced according to different end-conditions. Oblique shedding is one of the important three-dimensional features that could influence the amplitude, frequency and phase of the flow-induced forces.
