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*DSLOAD
Keyword type: step
This option allows for (a) the specification of section stresses on the boundary of
submodels, cf. the *SUBMODEL card and (b) the application of a
pressure on a facial surface.
For submodels there are two required
parameters: SUBMODEL and STEP. Underneath the *DSLOAD card faces are listed
for which a section stress will be calculated by interpolation from the global
model. To this end these faces have to be part of a *SUBMODEL card,
TYPE=SURFACE. The latter card also lists the name of the global model results
file. The STEP parameter specifies the step in the global model
which will be used for the interpolation. If results for more than one
increment within the step are stored, the last increment is taken. The distributed load type label convention is the same as for the
*DLOAD card. Notice that
- the section stresses are applied at
once at the start of the step, no matter the kind of procedure the user has
selected. For instance, the loads in a *STATIC procedure are
usually ramped during the step. This is not the case of the section stresses.
- the section stresses are interpolated from the stress values at the
nodes of the global model. These latter stresses have been extrapolated in
the global model calculation from the stresses at the integration
points. Therefore, the section stresses are not particular accurate and
generally the global equilibrium of the submodel will not be well fulfilled,
resulting in stress concentrations near the nodes which are fixed in the
submodel. Therefore, the use of section stresses is not recommended. A
better procedure is the application of nodal forces
(*CLOAD) at the intersection. These nodal forces may be
obtained by performing a preliminary submodel calculation with displacement
boundary conditions and requesting nodal force output.
For the application of a pressure on a facial surface there is one optional
parameter AMPLITUDE specifying the name of the amplitude by which the pressure
is to be multiplied (cf. *AMPLITUDE). The load label for
pressure is P.
First line:
- *DSLOAD
- For submodels: enter the parameter SUBMODEL (no argument) and STEP with its argument
Following line for surface loading on submodels:
- Element number or element set label.
- Distributed load type label.
Repeat this line if needed.
Following line for pressure application on a surface:
- Surface name.
- Load label (the only available right now is P for pressure)
- Pressure.
Repeat this line if needed.
Example:
*DSLOAD,SUBMODEL,STEP=4
Se1,P3
specifies hat on face 3 of all elements belonging to set Se1 the section
stress is to be determined by interpolation from step 4 in the global model.
Example files: .
Next: *DYNAMIC
Up: Input deck format
Previous: *DLOAD
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guido dhondt
2017-04-02