Appendix B - State Variable Outputs
This section provides a list of the solution dependent state variable outputs produced by Advanced Material Exchange. There are a total of 21 state variables computed and updated by the Helius PFA user subroutine at each integration point in the model for fiber filled materials and 16 for unfilled materials. Some of the state variables may be unused depending on the features included in your analysis.
The finite element solver stores the converged values of the state variables in the same manner it stores values for typical element outputs such as stress and strain. A unique file (*.mct) is generated for each analysis. This file contains a complete list of the state variables that apply to your model. The *.mct file is the best reference for understanding the meaning of each state variable.
ANSYS State Variables (SVARs)
| SVAR | Description |
|---|---|
| SVAR1 | Gauss point degradation status (1 = Not Ruptured, 2 = Ruptured) |
| SVAR2 | For internal use only |
| SVAR3 | Local matrix 11 stress |
| SVAR4 | Local matrix 22 stress |
| SVAR5 | Local matrix 33 stress |
| SVAR6 | Local matrix 12 stress |
| SVAR7 | Local matrix 13 stress |
| SVAR8 | Local matrix 23 stress |
| SVAR9 | Matrix tangent modulus |
| SVAR10 | Matrix effective plastic strain |
| SVAR11 | Matrix effective stress |
| SVAR12 | Weld surface strength reduction factor. This variable is only applicable to analyses that have weld surfaces activated. It is useful for visualizing the location of weld surfaces in your part and understanding the reduction in strength applied to each element on the weld surface. |
| SVAR13 | Matrix failure criterion index. This variable is a continuous real variable that ranges from 0.0 to 1.0. It is used to indicate the fraction of the matrix failure criterion that has been satisfied. For example, when SVAR13 = 0.0, the matrix stress state is zero. When SVAR13 = 1.0, the matrix stress state has initiated failure. SVAR13 is computed as the left hand side of Eq. 9 in The Rupture Model. |
| SVAR14 | Failure mode. SDV14 = 0 represents no failure, SVAR14 = 1 represents a tensile failure, and SVAR14 = 2 represents a compressive failure. |
| SVAR15 | Stress drop parameter μ for a failed integration point under a compressive stress state. SDV15 will range from 0.0 < μ ≤ 1.0. |
| SVAR16 | Fiber filled materials: Aspect ratio of the fiber. Unfilled materials: Stress State. SVAR16 = 1 represents a tensile dominated stress state and SVAR16 = 2 represents a compressive dominated stress state. |
| SVAR17 | Fiber volume fraction |
| SVAR18 | 1st eigenvalue of the fiber orientation tensor |
| SVAR19 | 2nd eigenvalue of the fiber orientation tensor |
| SVAR20 | 3rd eigenvalue of the fiber orientation tensor |
| SVAR21 | Stress State. SVAR21 = 1 represents a tensile dominated stress state and SVAR21 = 2 represents a compressive dominated stress state. |
Nastran Results
Nastran results are identified with normal result labels as opposed to state variable numbers.
| Result | Description |
|---|---|
| DAMAGE STATE | Gauss point degradation status (1 = Not Ruptured, 2 = Ruptured) |
| MATRIX TANGENT MODULUS | The tangent elastic modulus of the matrix constituent. |
| MATRIX EFFECTIVE PLASTIC STRAIN | The effective plastic strain of the matrix constituent. |
| MATRIX EFFECTIVE STRESS | The effective stress of the matrix constituent. |
| WELD SURFACE STRENGTH REDUCTION FACTOR | This result is only applicable to analyses that have weld surfaces activated. It is useful for visualizing the location of weld surfaces in your part and understanding the reduction in strength applied to each element on the weld surface. |
| FAILURE INDEX | This result is a continuous real variable that ranges from 0.0 to 1.0. It is used to indicate the fraction of the matrix failure criterion that has been satisfied.0.0 = the matrix stress state is zero. 1.0 = the matrix stress state has initiated failure. This result is computed as the left hand side of Eq. 9 in The Rupture Model. |
| FAILURE MODE | Failure mode. 0 represents no failure, 1 represents a tensile failure, and 2 represents a compressive failure. |