Note that in Ansys Polydata, the group of criteria described in Multiple Criteria is called “criterion", while the criterion described in Criterion Definition is called "sub-criterion".
After you have defined your simulation, you can specify the criteria to interrupt the evolution in the Numerical parameters item from the F.E.M. Task menu.
Numerical parameters
In the Numerical parameter menu, select one of the following:
Modify the evolution parameters
or
Modify the transient iterative parameters
These open the Evolution parameters menu and the Transient iterative parameters menu, respectively, where you can select the Management of interruption criteria item. This will bring up the Management of interruption criteria menu.
If you want to add a new group of criteria, click the Add a criterion item.
Add a criterion
The new group of criteria receives a name: Stop # [index]. You can change the name of the group of criteria by clicking Change name of the criterion.
Change name of the criterion
When prompted, enter the new name of the group of criteria.
To add a new criterion to the group, click the Add a sub-criterion item.
Add a sub-criterion
A criterion is defined by default. For example:
If the minimum of norm of field COORDINATES on domain R,
is lower or equal to 0,
the criterion becomes TRUE.
This is just an example, because the default definition for the criterion depends upon the fields computed during the simulation. In order to modify the criterion, perform the following steps:
Click the Select a field item, to select or modify the
field.
Select a field
Ansys Polydata will provide you with choices from different fields. Click the item corresponding to your choice, and then click the Upper level menu item on the top of the menu after you have selected the field.
Click the Select a restriction of the field item to select or modify the restriction function
. This item is available for non-scalar
fields only.
Select a restriction of the field
If you have selected the coordinates for the field, you can compute the length, area, or volume of the domain by clicking the length/surface/volume of domain item.
length/surface/volume of domain
Select the Norm (magnitude) item if you want to compute the norm of a vector for the restriction. This is the default for vectors.
Norm (magnitude)
Select the item related to a component (first component of field, second component of field, etc.) if you want to extract a component of a vector or a tensor for the restriction.
first component of field
Click the Upper level menu item after you have selected the restriction function.
Click the Select a function item to select or modify the function to compute the check value.
Select a function
Important: Note that this item is only available if the restriction function is not length/surface/volume of domain.
Select the minimum value item if you want to compute the minimum of restricted values
.
minimum value
Select the maximum value item if you want to compute the maximum of restricted values
.
maximum value
Select the average value item if you want to compute the average of restricted values
.
average value
Select the value at position item if you want to extract the value of restricted values
, at the node closest to a
particular position.
value at position
When prompted, enter the coordinates of the position.
Select the weighted average value item if you want to compute the weighted average of restricted values
.
weighted average value
Select the integral value item if you want to compute the integral of restricted values
.
integral value
Click the Upper level menu item after you have selected the function to compute the check value.
Click the Select a domain item to select or modify the domain where the criteria will be evaluated. By default, the selected domain is the domain associated with the field.
Select a domain
Select the Define domain of the sub-criterion item in order to select or modify the domain where the criterion will be evaluated. By default, the domain of the criterion is the domain associated with the field.
Define domain of the
sub-criterion
The top list displays the current domain. If you want to change this, select a domain in the bottom list and click the menu item. The top list will be updated and will contain the selected domain. Only one topo-object (domain or boundary) can be selected.
After you have selected the domain where the criteria will be evaluated, click the Upper level menu menu item.
If the desired domain or boundary is not displayed, you can create a new one by clicking the Create a new topo-object item.
Create a new topo-object
The top list will display all of the existing topo-objects.
Select an initial topo-object in the top list, and click the Select object 1 menu item to confirm your choice.
Select a second topo-object in the top list, and click the Select object 2 menu item to confirm your choice.
Select the type of operation from the following choices: intersection to create a new region from the intersection of the selected topology objects; or union to create a new region that is a combination of the selected topology objects.
Finally, specify a name and click the create menu item to create the new topo-object.
After you have completed these steps, the new region will be accessible in the top list and may be used to create yet another new region. This new region will be also accessible from the top list of the Define domain of sub-criterion panel, and it may be selected as a domain where the criterion will be evaluated.
Note that you can only perform topological operations between topo-objects of the same dimension.
The name of a topo-object may be modified by selecting the Modify the name of a topo-object item.
Modify the name of a topo-object
Item
In the top list, select the topo-object whose name you want to modify.
Click the Select object menu item to confirm your choice.
Enter the new name and click the modify menu item to change the name.
Finally, click the Upper level menu menu item.
You can delete a topo-object by selecting the Delete a topo-object item.
Delete a topo-object Item
In the top list, select the topo-object for deletion.
Click the Select object menu item to confirm your choice.
Click the delete menu item and click the Upper level menu menu item.
After you have specified the domain where the criteria will be evaluated, click the Upper level menu item.
Click the Select the type of criterion item to select or modify the inequality test.
Select the type of criterion
Click the greater than item if you want apply the test:
.
greater than
Click the greater or equal to item if you want apply the test:
.
greater or equal to
Click the lower than item if you want apply the test:
.
lower than
Click the lower or equal to item if you want apply the test:
.
lower or equal to
After you have specified the type of inequality test, click the Upper level menu item.
Click the Modify the limit value item to set the limit value of the criteria.
Modify the limit value
When prompted, specify the new limit value.
To modify an existing criterion of the group, click the Modify sub-criterion # [index] item. For example, to modify the first criterion of the group, select the following:
Modify sub-criterion # 1
A menu will appear, which has the same items as the menu described previously for Add a sub-criterion. You can modify the field, the restriction function, the function to compute the check value, the domain where the criteria will be evaluated, the inequality test, and the limit value.
If you want to remove a criterion from the group, click the Remove a sub-criterion item.
Remove a sub-criterion
Select the criterion for removal from the group, and click the Upper level menu item.
After all of the criteria of the group have been defined, click the Upper level menu item.
To modify an existing group of criteria, click the Modify criterion [criterion name] item. For example, to modify the first criterion when it has the default name, select the following:
Modify criterion Stop # 1
A menu will appear, which has the same items as the menu described previously for Add a criterion. You may change the name of the group of criteria, add a new criterion to the group, or modify or remove an existing criterion of the group.
If you want to remove an existing group of criteria, click Remove a criterion.
Remove a criterion
Select the criterion for removal, and click the Upper level menu item.
After all of the groups of criteria have been defined, click the Upper level menu item.
Upper level menu