Changeset 554

Timestamp:

Nov 16, 2004, 2:43:04 PM (20 years ago)

Author:

ole

Message:

Added linear friction term

File:

• inundation/ga/storm_surge/pyvolution/shallow_water.py (modified) (1 diff)

inundation/ga/storm_surge/pyvolution/shallow_water.py

@@ -861 +861 @@
     from shallow_water_ext import manning_friction
     manning_friction(g, eps, w, z, uh, vh, eta, xmom_update, ymom_update)
+
+
+def linear_friction(domain):
+    """Apply linear friction to water momentum
+    """
+
+    from math import sqrt
+
+    w = domain.quantities['level'].centroid_values
+    z = domain.quantities['elevation'].centroid_values
+    h = w-z
+
+    uh = domain.quantities['xmomentum'].centroid_values
+    vh = domain.quantities['ymomentum'].centroid_values
+    eta = domain.quantities['friction'].centroid_values    
+    
+    xmom_update = domain.quantities['xmomentum'].semi_implicit_update
+    ymom_update = domain.quantities['ymomentum'].semi_implicit_update    
+    
+    N = domain.number_of_elements
+    eps = domain.minimum_allowed_height
+    
+    for k in range(N):
+        if eta[k] >= eps:
+            if h[k] >= eps:
+                S = -eta[k]/h[k]
+
+                #Update momentum
+                xmom_update[k] += S*uh[k]
+                ymom_update[k] += S*vh[k]
+            
+