Changeset 5618


Ignore:
Timestamp:
Aug 6, 2008, 2:41:57 PM (15 years ago)
Author:
ole
Message:

Added comments and documentation about CFL condition.

Location:
anuga_core
Files:
2 edited

Legend:

Unmodified
Added
Removed
  • anuga_core/documentation/user_manual/anuga_user_manual.tex

    r5566 r5618  
    32823282In the computations presented in this paper we use an explicit Euler
    32833283time stepping method with variable timestepping adapted to the
    3284 observed CFL condition.
    3285 
     3284observed CFL condition:
     3285
     3286\begin{equation}
     3287  \delta t = \min_{k,i=[0,1,2]}  r_k/v_i
     3288  \label{eq:CFL condition}
     3289\end{equation}
     3290where $r_k$ is the radius of the $k$th triangle and $v$ is the maximal velocity across the edge joining triangle $k$
     3291and it's neighbour triangle $i$ as calculated by the numerical flux function using the central upwind scheme of \cite{KurNP2001}. 
    32863292
    32873293\section{Flux limiting}
  • anuga_core/source/anuga/shallow_water/shallow_water_ext.c

    r5442 r5618  
    17591759        if (max_speed > epsilon) {
    17601760       
    1761           // Original CFL calculation
     1761          // Apply CFL condition for triangles joining this edge (triangle k and triangle n)
     1762         
     1763          // CFL for triangle k
    17621764          timestep = min(timestep, radii[k]/max_speed);
     1765         
    17631766          if (n>=0)
     1767            // Apply CFL condition for neigbour n (which is on the ith edge of triangle k)
    17641768            timestep = min(timestep, radii[n]/max_speed);
    17651769         
Note: See TracChangeset for help on using the changeset viewer.