A three-dimensional numerical simulation is performed to study a heaving airfoil with an immersed boundary method. Flow around a heaving airfoil has been widely investigated by using two-dimensional simulation; while few previous works discussed the physical behavior of flow over heaving airfoils with three-dimensional effects. The purpose of this study is to identify characteristic features of flow over heaving airfoils in three-dimensional simulation in comparison with those in two-dimensional cases. In particular, the vortical wakes downstream of the heaving ellipsoid wing is characterized by a reversed-Karman-vortex-street-like structure, which is a reduced reversed-Karman vortex street. The implication of this characteristic is found to be the reduced leading-edge vortex on the 3D wing.
In order to fulfill the computational requirement, a parallel implementation of the immersed boundary method (Zhang & Zheng ) is presented. The pressure Poisson equation is solved with the assistance of a portable scientific parallel computational library (PETSc). This code is validated with a case of flow over a stationary sphere. The parallel performance is also demonstrated.