Conditions at the Downstream Boundary for Simulations of Viscous Incompressible Flow

Download or read book Conditions at the Downstream Boundary for Simulations of Viscous Incompressible Flow written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proper specification of boundary conditions at artificial boundaries for the simulation of time-dependent fluid flows has long been a matter of controversy. A general theory of asymptotic boundary conditions for dissipative waves is applied to the design of simple, accurate conditions at downstream boundary for incompressible flows. For Reynolds numbers far enough below the critical value for linear stability, a scaling is introduced which greatly simplifies the construction of the asymptotic conditions. Numerical experiments with the nonlinear dynamics of vortical disturbances to plane Poiseuille flow are presented which illustrate the accuracy of our approach. The consequences of directly applying the scalings to the equations are also considered. Hagstrom, Thomas Glenn Research Center NASA ORDER C-99066-G; RTOP 505-62-21...