An Adaptive Cut-Cell Method for Incompressible Flows

Date: Thursday, April 23, 2009
Time: 10:00am - 11:00am
Location: LBNL Bldg. 50F, Room 1647

Speaker:
Dr. Michael F. Barad, P.E.
Environmental Fluid Mechanics Laboratory
Stanford University

Abstract:

I will present our cut-cell block-structured adaptive mesh
refinement (AMR) computational fluid dynamics model and its
application to the study of highly nonlinear multiscale
environmental flows. The model is based on the solution of the
variable density incompressible Navier-Stokes equations in two or
three dimensions, including air/water and fluid/solid interfaces and
the transport of scalars. It is composed of a second-order-accurate
finite volume projection method, which includes a stable
slope-limited Godunov discretization of the advective terms. We
discretize irregular domains as a collection of (cut-cell) control
volumes formed by the intersection of the domain with Cartesian grid
cells. The control volumes naturally fit within high-performance
block data-structures. This methodology is combined with finite
volume AMR discretizations based on two-way flux matching at
refinement boundaries to obtain a conservative method that is
second-order accurate in time and space. The cut-cell method enables
dynamic coarsening and refinement of arbitrarily complex domains as
a simulation progresses, a requirement for AMR and geometric
multigrid. I will present several applications of the model,
including: gravitational exchange flows, internal gravity-waves,
odorant detection, and diffusion-driven propulsion. This work is a
collaborative effort, primarily with the Applied Numerical
Algorithms Group at Lawrence Berkeley National Laboratory.

Host of Seminar:

    John Bell