GfsSpatialSum

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GfsSpatialSum defines a new GfsConstant containing the spatial sum (spatial integral) of a GfsFunction.

The syntax in parameter files is

[ GfsConstant ] [ GfsFunction ] 

For example, the following computes the spatial sum of Variable U at every time step, placing the result in a Constant Ubar

 SpatialSum { istep = 1 } Ubar U

Examples

  • Forced isotropic turbulence in a triply-periodic box
  •   SpatialSum { istep = 1 } SU U
    

      SpatialSum { istep = 1 } SV V
    

      SpatialSum { istep = 1 } SW W
    

      SpatialSum { istep = 1 } Un Velocity
    

      SpatialSum { istep = 1 } Dissipation { 
          return MU*(dx("U")*dx("U") + dy("U")*dy("U") + dz("U")*dz("U") + 
                     dx("V")*dx("V") + dy("V")*dy("V") + dz("V")*dz("V") +
                     dx("W")*dx("W") + dy("W")*dy("W") + dz("W")*dz("W"));
      } 
    

      SpatialSum { istep = 1 } FluctKinEn {
          return 0.5*((U - Ubar)*(U - Ubar) + 
                      (V - Vbar)*(V - Vbar) +
                      (W - Wbar)*(W - Wbar));
      } 
    

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