Lab Home | Phone | Search
Center for Nonlinear Studies  Center for Nonlinear Studies
 Home 
 People 
 Current 
 Affiliates 
 Visitors 
 Students 
 Research 
 ICAM-LANL 
 Publications 
 Conferences 
 Workshops 
 Sponsorship 
 Talks 
 Colloquia 
 Colloquia Archive 
 Seminars 
 Postdoc Seminars Archive 
 Quantum Lunch 
 CMS Colloquia 
 Q-Mat Seminars 
 Q-Mat Seminars Archive 
 Archive 
 Kac Lectures 
 Dist. Quant. Lecture 
 Ulam Scholar 
 Colloquia 
 
 Jobs 
 Students 
 Summer Research 
 Visitors 
 Description 
 Past Visitors 
 Services 
 General 
 
 History of CNLS 
 
 Maps, Directions 
 CNLS Office 
 T-Division 
 LANL 
 
Wednesday, March 18, 2009
09:00 AM - 10:00 AM
CNLS Conference Room (TA-3, Bldg 1690)

Seminar

Numerical Analysis Seminar: Finite Volume/DG Schemes Based on Constrained Minimization Function Recovery

Panayot S. Vassilevski
Lawrence Livermore National Laboratory

Traditional finite volume discretizations of time dependent PDEs allow for straightforward computation of averaged (piecewise constant) values of the physical quantities involved (such as pressure, velocity, density and energy). However, in order to close the overall discretization scheme, certain derivatives (gradient or divergence) of some of these quantities are needed. On the example of the Euler equations of gas dynamics, we study an approach based on minimizing TV (total variation) functionals subject to equality and inequality constraints to construct smooth function recovery of the pressure and velocity from their average values. The constraints have physical meaning; namely, positivity of pressure (or internal energy) and the recovered functions to preserve (approximately) their averages computed by the finite volume scheme. Extensions to higher order DG (discontinuous Galerkin) schemes can be derived in the same manner. We illustrate the overall finite volume scheme with some preliminary numerical results.

Host: Mikhail Shashkov