Index  

Vn & vs imposed along boundary
Ver: 0
 

DESCRIPTION

For flow problems, entering this menu allows the user to specify essential boundary conditions for the momentum equation. The default values of vn and vs are both zero. A non-vanishing value can be selected for the normal component of the velocity in any geometry. A non-zero tangential velocity component can be imposed for for 2-D and 2-1/2-D flows. However, only vanishing tangential velocity components can be specified for 3-D flows.

The normal vector at a boundary is assumed to point out of the flow domain.

For the specified component of velosity, the current value is recalled, and the possibility of modifying it as given (when available).

  OPTIONS
  -1    
 Upper level menu
1
 Constant
The current component is constant on the corresponding boundary line or face
2
 Linear function of coordinates
A linear dependence upon the current space coordinates can be selected
NOTES If a fuly developed Poiseuille velocity profile is to be imposed, the user should select the inflow boundary condition type.   EXAMPLES For the simple shear flow (a fluid is sheared between two planes), the user should in select:   1 vanishing vn and vs along the fixed plane
2 vanishing vn and non-vanishing vs along the moving plane   SEE ALSO