Load case filtering calculations

A calculation is a set of the following items that the software uses to determine the most critical loads in your model:

• The method that the software uses for filtering the load cases.

• The load set to filter.When the software performs a load case filtering calculation, it performs each load case filtering calculation in the solution for all load cases in the load case set. That is, the software superposes the results from each load case set to select the most critical load cases.For additional information on load case sets, see Load case sets (load case filtering).

• The results to use in the calculation. To obtain the results:Specify the result type and, if applicable, the component of the result type in the calculation.Select the nodes or elements for which to retrieve the results.You can select the nodes or elements directly or indirectly from groups, parent/child relationships, or selection recipes.For more information on parent/child relationships, see Parent/child behavior in load case filtering calculations.

• A tolerance or pair of tolerances, depending on your selected method. The tolerance is the value the software uses to filter those load cases that fall between the value of the tolerance and the extremity of the enclosed 1D or 2D space in the method.

You can create multiple calculations individually, or you can copy or clone calculations and then edit each calculation. For more information, see Cloning load case filtering calculations.

Calculations appear in the Simulation Navigator under the Calculations node.

Method selection

The software has built-in methods that allow you to filter load cases to determine those most critical to your design.

When you select a method, the Calculation – Method Selection dialog box displays a graphical representation of the loads that are used in the method. You can also open a window that contains detailed technical information on the built-in method that you can refer to when defining the parameters.

Result selection

You can select any result type that is available in post-processing.

For each load in the load case filtering solution, the software retrieves a single result value for each node or element that you select. Because element-nodal results have multiple result values at a node, when you select an element-nodal result type, you must specify how the software obtains a single result value from the multiple result values at a node.

For example, you can have the software average all of the values into a single value, or you can have the software use the algebraic maximum or minimum value, and so on.

Node and element selection

To select the nodes or elements for which the software retrieves the results to use in a load case filtering calculation, you can:

• Select individual nodes or elements directly one at a time from the graphics window.

• Select several nodes or elements directly using a selection box in the graphics window.

• Select nodes or elements indirectly by selecting parent polygon geometry in the graphics window.

• Select nodes or elements indirectly by selecting groups that include nodes, elements, and parent geometry.

Individual calculations

The calculation uses the loads that are extracted from the set of results that are created from the results for all the nodes or elements that you select. You can select the nodes or elements directly or indirectly through parent/child relationships, groups, or selection recipes. For information on indirect selection through parent/child relationships or groups, see Parent/child behavior in load case filtering calculations.

The result type that you select determines whether the software uses results from nodes or elements. If in the Load Extraction dialog box, in the Result group, you set Result Type to:

• A nodal or element-nodal result, the software uses results for nodes.

• An elemental result, the software uses results for elements.

For example, suppose that in the Load Extraction dialog box you set Result Type to an elemental result type. If you set Entities Type to Elements, and select elements directly from the graphics window, the software creates the results set for the calculation from the elemental results for the elements that you select.

If you set Entities Type to Edges, and select polygon edges directly from the graphics window, the software creates the results set for the calculation from the elemental results for the elements that have an element edge that lies on the polygon edges that you select.

Tolerance specification

The software uses an applied tolerance or tolerances to filter load cases, which are represented by point coordinates in a 1D or 2D space. These points represent the values of the loads you extract using the Load Extraction dialog box.

Load values are filtered based on their proximity to the most extreme values of the loads. In a 2D space, the extreme points enclose the other points within a bounding rectangle or a convex hull. When you specify the tolerances, you specify the acceptable proximity from the extreme values within which loads are filtered.

The tolerance that you specify is a percentage. In general, you should use a tolerance of 0.1 or less. When you solve a calculation, if you find that the software filtered too many load cases, you can lower the tolerance and re-solve the calculation.

Depending on the method you select, you specify a single tolerance or a pair of tolerances. For example, if you choose:

• A bounding box method, you define a pair of tolerances, one for each load you extract.In this method, the software filters load cases based on a bounding rectangle and tolerances applied in the two axis directions.

• A convex hull method, you define a single tolerance.In this method, the software filters load cases based on a convex hull and an applied tolerance.

• A 1D min max method, you define a single tolerance.In this method, the software filters load cases based on the extreme ends of a single load axis and an applied tolerance.

Where do I find it?

Application	Pre/Post
Prerequisite	An active load case filtering solution
Simulation Navigator	Right-click Calculations→Create Calculation

How do I

Create a load case filtering calculation

Create and solve a convex hull calculation

Learn more

Parent/child behavior in load case filtering calculations

Extracting a single value from the set of results (load case filtering)

Sources manager (load case filtering)

Quick links

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Load Case Filtering method documentation

Load case filtering calculations, Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });