scholarly journals Computational Stability Analysis of Diffusion‐Deformation Processes at Finite Strains

PAMM ◽  
2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Siddharth Sriram ◽  
Elten Polukhov ◽  
Marc-André Keip
PAMM ◽  
2017 ◽  
Vol 17 (1) ◽  
pp. 543-544
Author(s):  
Elten Polukhov ◽  
Daniel Vallicotti ◽  
Marc-André Keip

2016 ◽  
Vol 44 (2) ◽  
pp. 113-120
Author(s):  
Péter Polcz ◽  

Abstract This paper concerns the computational stability analysis of locally stable Lotka-Volterra (LV) systems by searching for appropriate Lyapunov functions in a general quadratic form composed of higher order monomial terms. The Lyapunov conditions are ensured through the solution of linear matrix inequalities. The stability region is estimated by determining the level set of the Lyapunov function within a suitable convex domain. The paper includes interesting computational results and discussion on the stability regions of higher (3,4) dimensional LV models as well as on the monomial selection for constructing the Lyapunov functions. Finally, the stability region is estimated of an uncertain 2D LV system with an uncertain interior locally stable equilibrium point.


PAMM ◽  
2014 ◽  
Vol 14 (1) ◽  
pp. 483-484
Author(s):  
Daniel Vallicotti ◽  
Dominic Zäh ◽  
Christian Miehe

2011 ◽  
Vol 139 (9) ◽  
pp. 2976-2993 ◽  
Author(s):  
Jared P. Whitehead ◽  
Christiane Jablonowski ◽  
Richard B. Rood ◽  
Peter H. Lauritzen

The dynamical core of an atmospheric general circulation model is engineered to satisfy a delicate balance between numerical stability, computational cost, and an accurate representation of the equations of motion. It generally contains either explicitly added or inherent numerical diffusion mechanisms to control the buildup of energy or enstrophy at the smallest scales. The diffusion fosters computational stability and is sometimes also viewed as a substitute for unresolved subgrid-scale processes. A particular form of explicitly added diffusion is horizontal divergence damping. In this paper a von Neumann stability analysis of horizontal divergence damping on a latitude–longitude grid is performed. Stability restrictions are derived for the damping coefficients of both second- and fourth-order divergence damping. The accuracy of the theoretical analysis is verified through the use of idealized dynamical core test cases that include the simulation of gravity waves and a baroclinic wave. The tests are applied to the finite-volume dynamical core of NCAR’s Community Atmosphere Model version 5 (CAM5). Investigation of the amplification factor for the divergence damping mechanisms explains how small-scale meridional waves found in a baroclinic wave test case are not eliminated by the damping.


Sign in / Sign up

Export Citation Format

Share Document