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docs:utils:couette [2009/02/13 08:32]
gibson created
docs:utils:couette [2009/02/13 08:45]
gibson
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 [[docs:​utils:​couette:​alloptions|Complete option list]] [[docs:​utils:​couette:​alloptions|Complete option list]]
  
-==== time intervals ====+===== time intervals ​=====
  
 The integration starts at ''​t=T0''​ and saves data at times ''​t = T0 + n dT'',​ exactly. The ''​dt'' ​ The integration starts at ''​t=T0''​ and saves data at times ''​t = T0 + n dT'',​ exactly. The ''​dt'' ​
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 so that the save interval is exactly what you asked for. Data is saved to disk in files named ''​u0.ff,​ u1.ff, u2.ff, ...''​ if ''​t''​ takes on integer values or filenames with four-digit precision if ''​t''​ otherwise, e.g. ''​u0.000.ff,​ u0.125.ff, u0.250.ff, ...''​. The integration stops when ''​t = T0 + n dT > T1.''​ so that the save interval is exactly what you asked for. Data is saved to disk in files named ''​u0.ff,​ u1.ff, u2.ff, ...''​ if ''​t''​ takes on integer values or filenames with four-digit precision if ''​t''​ otherwise, e.g. ''​u0.000.ff,​ u0.125.ff, u0.250.ff, ...''​. The integration stops when ''​t = T0 + n dT > T1.''​
  
-==== timestepping ====+===== timestepping ​=====
  
 The ''​-ts''​ or ''​--timestepping''​ sets the finite-difference time stepping algorithm. It takes the following ​ The ''​-ts''​ or ''​--timestepping''​ sets the finite-difference time stepping algorithm. It takes the following ​
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 |''​sbdf4''​| ​ 4  | Semi-implict Backwards Differentiation| |''​sbdf4''​| ​ 4  | Semi-implict Backwards Differentiation|
  
-==== nonlinearity ====+===== nonlinearity ​===== 
 + 
 +The ''​-nl''​ or ''​--nonlinearity''​ specifies the method for calculating the 
 +nonlinearity u⋅∇u in the Navier-Stokes equation. 
 + 
 +^  value  ^      ^method^ 
 +|  ''​rot'' ​ |  (∇×u)×u ​ |rotational| 
 +|  ''​conv''​ |  u⋅∇u ​  ​|convection| 
 +|  ''​div'' ​ |  ∇⋅(uu) ​ |divergence| 
 +| ''​skew'' ​ |  (u⋅∇u + ∇⋅(uu))/​2 |skew-symmetric| 
 +| ''​alt'' ​  ​| ​  ​|alternating between ''​conv''​ and ''​div''​| 
 + 
 +===== mean constraints =====
  
 ====== Usage examples ====== ====== Usage examples ======
  
  
-Integrate ​ 
docs/utils/couette.txt · Last modified: 2010/02/02 07:55 (external edit)