Index

Fs & vn imposed along boundary

Ver: 0
 

DESCRIPTION

For flow problems, entering this menu allows the user to specify mixed essential/natural boundary conditions for the momentum equation. The default values of fs and vn are both zero. A non-vanishing value can be selected for the normal component of the velocity in any geometry. A non-zero tangential force component can be imposed for for 2-D and 2-1/2-D flows. However, only vanishing tangential force 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 the boudnary condition, the current value is recalled, and the possibility of modifying it is 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
 
With vanishing parameters, this boundary conditions applies to symmetry conditions for flow problems.
The user should be aware of the system of units, if dimensional values are used.
The units for fs and vn are :
 
Parameter
Mass
Length
Time
Temperature
fs
1
-1
-2
-
vn
-
1
-1
-
SEE ALSO