PROPERTY LOADS HYDROSTA [lname] [lnumb] part [opart] pres [dof [pnam1 pnam2]]

        

This command is used to apply hydrostatic loads.

lname = name of the loadcase, used for later references.

lnumb = loadcase number (integer, default=1).

part = part to be loaded, line, surface or set.

opart = optional part of next higher order from loaded part, which contains the elements to be loaded. Only required when there is ambiguity over which elements are to be loaded. See note 2.

pres = size of hydrostatic load.

dof = direction of hydrostatic load 0 or NORMAL = normal to element face/edge (default) 1 or X = global x 2 or Y = global y 3 or Z = global z

pnam1 = name of point where hydrostatic load = `pres' above

pnam2 = name of point where hydrostatic load = 0.

The PROPERTY LOADS HYDROSTA command applies a hydrostatic load to all elements on a part of a structure. The load can either be applied on a line or on a surface. In both cases there are two possibilities:

a line with elements = line load on beams; for the `NORMAL' direction a positive pressure acts in the negative z direction of the beam local axis.

a line without elements = line load on one side of a surface e.g. axi-symmetric

(edge of a surface) elements, for the `NORMAL' direction a positive pressure acts in the plane of the elements in the inward direction.

a surface with elements = distributed load on shell elements, for the 'NORMAL' direction a positive pressure acts in the direction of the surface normal.

a surface without elements = distributed load on one face of body elements, for the

(face of a body) `NORMAL' direction a positive pressure acts in the direction of the inward normal to the body.

Notes:

1.

Loadcase numbers
The loadcase number is only used by the pre-interface programs to group loads together. If no number is given the default is 1.

2.

Ambiguous loading
Ambiguity over which elements are loaded will only arise when the part that is loaded is attached to more than one other part, (for example where a load is applied to a line which is attached to two surfaces). Any ambiguity about which elements will be loaded can be resolved by specifying the part containing the elements to be loaded in the definition of the load.
The command is restricted to only allow certain combinations of parts i.e. point/line, line/surface and surface/body. In the case of sets, a similar relationship is required between the parts in the set.
If the load is to be applied to several of the parts sharing the loaded part, the command should be repeated for each part containing elements.
If the second (optional) part is not given then the load is applied to the part with the lower entity number.

3.

`NORMAL' loads on lines
Most of the interfaces do not support a `NORMAL' load on beam elements, instead it is necessary to specify the required direction (dof).

Examples:

1.

PROPERTY LOADS HYDROSTA LO3 1 S2 12.1 NORM P19 P70

Create and apply a hydrostatic load LO3 in loadcase 1 to surface S2 , normal to the surface. The load will vary linearly from 12.1 at point P19 to 0.0 at point P70. Points P19 and P70 need not be attached to surface S2.

See also the following commands

'LABEL GEOMETRY LOADS'
'LABEL MESH LOADS'
'UTILITY DELETE LOADS'
'UTILITY TABULATE GEOMETRY LOADS'