HyperView User's Guide

Minimum Averaging

Minimum Averaging

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Minimum Averaging

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Minimum averaging extracts the minimum values from the surrounding elements attached to a node.  The tensor and vector components are extracted and the invariants are computed for each element (or corner) prior to averaging to a node.  For results components, the corresponding components from each element corner (or centroid) are extracted and then the minimum value is assigned to the shared node.  For invariants, the corresponding invariants are calculated from each tensor at the element corners and then the minimum value is assigned to the node.

For example, as shown in Nodal Averaging of Elemental Results, there are four tensors, [A2], [B1], [C3], and [D4] at four corners at Node 400.

The minimum average of the xx component at Node 400 is:

min_averaging_formula1

For the minimum average of an invariant such as von Mises, the von Mises value for all tensor [A2], [B1], [C3] , and [D4] are computed, then they are averaged as follows:

min_averaging_formula2

The averaging methods for solid elements and shell elements are different.

Element Type

Reference System

Projection Rule


Solid

Global

N/A

All corresponding tensors and vectors are transformed to the global coordinate system and then a component or invariant is averaged as explained above.


Analysis

N/A

All corresponding tensors and vectors are left in their original coordinate system (no transformation occurs) and then a component or invariant is averaged as explained above.  In this case, each participating element result can be in a different system.  Minimum averaging for components ignores variations in systems.  Since invariance does not depend on the coordinate system, all reference systems will produce the same results for invariants.


Elemental

N/A

All corresponding tensors and vectors are transformed to the elemental coordinate system and then a component or invariant is averaged as explained above.  In this case, each participating element result can also be in a different system.   Minimum averaging for components ignores variations in systems.  Since invariance does not depend on the coordinate system, all reference systems will produce the same results for invariants.


User-defined

N/A

All corresponding tensors and vectors are transformed to the user-defined coordinate system and then a component or invariant is averaged as explained above.

Shell

Global

ON

All corresponding tensors and vectors are transformed to the projected system (following the projection rule) of the participating elements and then the component or invariants are averaged as explained above.

As a result, even if the reference system is the same, the projected systems in participating elements can be different.  Minimum averaging for components ignores variations in systems.



OFF

All corresponding tensors and vectors are transformed to the global coordinate system and a component or invariant is then averaged as explained above.


Analysis

N/A

All corresponding tensors and vectors are left in their original coordinate system (no transformation occurs) and then a component or invariant is averaged as explained above.  In this case, each participating element result could be in a different system. Minimum averaging for components ignores variations in systems.  Since invariance does not depend on the coordinate system, all reference systems will produce the same results for invariants.


Elemental

N/A

All corresponding tensors and vectors are transformed to the elemental coordinate system and then a component or invariant is averaged as explained above.  In this case, each participating element result could also be in a different system.  Minimum averaging for components ignores variations in systems.  Since invariance does not depend on the coordinate system, all reference systems will produce the same results for invariants.


User-defined

ON

All corresponding tensors and vectors are transformed to the projected system (following the projection rule) of the participating elements and then the component or invariants are averaged as explained above.

As a result, even if the reference system is the same the projected systems in participating elements can be different.  Minimum averaging for components ignores variations in systems.



OFF

All corresponding tensors and vectors are transformed to the User-defined coordinate system and a component or invariant is then averaged as explained above.

Valid reference coordinate system: All (Global, Analysis, Elemental, and User-defined)

See also

Variation Percentage Control

Contour Panel