Index

Vx,vy(,vz) imposed along boundary
Vr,vz imposed along boundary

Ver: 1   DESCRIPTION Entering this menu allows the user to specify essential boundary conditions for the momentum equation, in a cartesian reference frame (cylindrical in axisymmetric geometries). The imposed velocity vector is the result of an angular velocity around a given axis and a translation velocity.

Two points define and orient the rotation axis, while the translation velocity is specified by means of its three components in a cartesian reference frame. The rotation axis is always the Z axis for axisymmetric problems.
 

 OPTIONS
 
-1
 Upper level menu
   1 
 Modify rotation center
Note here that the rotation axis is oriented from the origin of the coordinate system towards positive Z coordinates.
2
 Modify  angular velocity
The angular velocity is specified with respect to the Z axis
3
 Modify  translation velocity
The two components of the translation velocity in a cartesian reference frame are specified here
-1
 Upper level menu
   1 
 Modify  1st point of the axis
Note here that the rotation axis will be oriented from the first to the second point, and that the angular velocity will be defined with respect to this orientation
2
 Modify  2nd point of the axis
3
 Modify  angular velocity
The angular velocity is specified with respect to the oriented rotation axis
4
 Modify  translation velocity
The three components of the translation velocity in a cartesian reference frame are specified here
NOTES
If the flow problem is described with respect to a rotating reference frame, some boundaries will rotate. This current type of boundary conditions is an easy tool for imposing tangential velocity components.


SEE ALSO