Changeset 5224

Timestamp:

Apr 21, 2008, 5:16:38 PM (17 years ago)

Author:

ole

Message:

Work done during Water Down Under 2008.
Tried alternative CFL conditions as suggested by Ted Rigby.
They are kept commented out.

File:

• anuga_core/source/anuga/shallow_water/shallow_water_ext.c (modified) (5 diffs)

anuga_core/source/anuga/shallow_water/shallow_water_ext.c

@@ -231 +231 @@
   _rotate(q_right_rotated, n1, n2);
 
-  z = (z_left+z_right)/2; // Average elevation values
+  z = (z_left+z_right)/2; // Average elevation values. 
+                          // Even though this will nominally allow for discontinuities 
+                          // in the elevation data, there is currently no numerical 
+                          // support for this so results may be strange near jumps in the bed.
 
   // Compute speeds in x-direction
@@ -1769 +1772 @@
       n = neighbours[ki];
       if (n < 0) {
-        m = -n-1; // Convert negative flag to index
+        // Neighbour is a boundary condition
+        m = -n-1; // Convert negative flag to boundary index
         
         qr[0] = stage_boundary_values[m];
@@ -1776 +1780 @@
         zr = zl; // Extend bed elevation to boundary
       } else {
+        // Neighbour is a real element
         m = neighbour_edges[ki];
         nm = n*3+m; // Linear index (triangle n, edge m)
@@ -1847 +1852 @@
           if (n>=0) 
             timestep = min(timestep, radii[n]/max_speed);
+          
+          // Ted Rigby's suggestion
+          //if (n>=0) {             
+          //  timestep = min(timestep, 0.8*(radii[k]+radii[n])/max_speed);
+          //} else {
+          //  timestep = min(timestep, radii[k]/max_speed);
+          // }
+          
+          
+          // Ole's modification
+          //if (n>=0) {             
+          //  timestep = min(timestep, max(radii[k],radii[n])/max_speed);
+          //} else {
+          //  timestep = min(timestep, radii[k]/max_speed);
+          //}
+          
+          
         }
       }
       
-    } // End edge i
+    } // End edge i (and neighbour n)
     
     
@@ -2010 +2032 @@
     in domain.
 
-    Compute total flux for each conserved quantity using "flux_function_central"
+    THIS IS AN EXPERIMENTAL FUNCTION - NORMALLY flux_function_central IS USED.
+    
+    Compute total flux for each conserved quantity using "flux_function_kinetic"
 
     Fluxes across each edge are scaled by edgelengths and summed up