Topical Problems of Fluid Mechanics


Institute of Thermomechanics AS CR, v.v.i.	CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics	MIO Université du Sud Toulon Var - AMU - CNRS - IRD	Czech Pilot centre ERCOFTAC

Numerical Tests of Far-Field Boundary Conditions for Stably Stratified Flows
T. Bodnár, Ph. Fraunié, H. Řezníček
Abstract:
This numerical study presents the results of simulations of stably stratified wall-bounded flows. The effect of artificial far-field boundary conditions is studied in detail. The standard homogeneous Neumann condition for pressure is replaced by a non-homogeneous condition depending on local velocity and its gradient. The two-dimensional tests are performed for the case of flow over a low isolated hill. The simulations on computational domains with three different heights are discussed to evaluate the performance of the new far-field artifcial boundary condition. The model is based on Boussinesq approximation of non-homogeneous Navier-Stokes equations, solved using artificial compressibility method, looking for a steady solution.
Keywords:
Boussinesq approximation, stable stratification, far-field boundary condition, artifcial compressibility, finite-difference, finite-volume

Fulltext: PDF DOI: https://doi.org/10.14311/TPFM.2019.003

In Proceedings Topical Problems of Fluid Mechanics 2019, Prague, 2019 Edited by David Šimurda and Tomáš Bodnár, pp. 17-24 ISBN 978-80-87012-69-7 (Print) ISSN 2336-5781 (Print)