Altair HyperLife 2020 Release Notes
New Features
- Vibration Fatigue
- Vibration fatigue analysis can be performed with the following loading
options to predict fatigue in the frequency domain:
- Random Response Fatigue with PSD Stress Input
- PSD stress from a random response analysis is input to perform random response fatigue analysis with stress life (SN) and strain life (EN) approaches. Currently, OptiStruct (H3D) result formats are only supported as an input file.
- Random Response Fatigue with PSD Input (mag and phase OR real and imag)
-
FRF stresses (from FRF analysis), together with PSD as loading, are input to perform random response fatigue analysis with stress life (SN) and strain life (EN) approaches. Currently, OptiStruct (H3D), Nastran (OP2), and Abaqus (ODB) result formats are supported as input files. PSD has to be input in CSV format.
- Sine Sweep Fatigue
- With the input swept-sine, fatigue analysis can be performed in sine sweep vibration to determine the fatigue life of the specimen with stress life (SN) and strain life (EN) approaches. Currently, OptiStruct (H3D), Nastran (OP2), and Abaqus (ODB) result formats are supported as input files.
- Modal Superposition
- Fatigue analysis can be performed when modal stresses and modal
participation factors are available in two different file
inputs.
Modal stresses are multiplied by modal participation factors then summed at each point in time. The modal stress file (geometry) is supported for the H3D file format. The supported modal participation factor file formats are PCH and MRF. Currently, only time domain results (from transient analysis) are supported.
- Safety Factor Estimation
- “Safety Factor” is available as output with SN analysis for constant mean stress and constant stress ratio.
- Temperature Influence
- Temperature influence is considered based on the FKM guideline by input “Temperature factor” to modify the endurance limit for SN analysis.
- Surface Finish
- User-defined input value is enabled in the Material tool.
- Surface Treatment
- User-defined input value is enabled in the Material tool.
- Seam Weld Fatigue
- Two row fillet welds and overlap welds are supported (only with Time Series loading).
Enhancements
- Setup Analysis
-
- Type of Loading
- The following fatigue loading options are available to set
in the collated stress-life (SN) and strain-life (EN)
tools:
- Time Series
- Transient Response
- Modal Superposition
- Random (PSD Stress)
- Random (Input PSD with FRF)
- Sine Sweep
One of the above options is selected based on the available fatigue loading history to be input in the Load Map tool. Time Series is set as default
- Damage Models
- Damage models are the different probability density functions available for vibration fatigue when the Type of Loading is set to Random.
- User Warning for Supported Input File Formats
- With file load or file drag-and-drop-drop together with the "Type of Loading", a warning pops up to hint you about the supported file types.
- Stress Combination
- Default stress combination is set to "Abs max principal".
- Layer Selection
- For shell models, default layer is set to "Worst".
- Material Tool
- The following enhancements are available in the Material tool:
- When FOS is selected as the fatigue analysis type, the Material tool is dynamically updated and streamlined to show input parameters specific to FOS-Dang Van calculations.
- Temperature factor: An exclusive column is added for "Temperature factor" input (based on the FKM guideline).
- User defined Values: The UI is updated to accommodate user input values for "Surface treatment" and "Surface finish".
- Load Mapping Tool
- The following enhancements are available in the Load Map tool:
- Block Loading Utility: The format has been updated for better simplified viewing when written out.
- The LDM, Scale and offset input can’t accept zero.
- The quasi-static load increments are available as loadsteps
(under "Subcase") from OptiStruct
and Abaqus simulations.
Only the last step of the increments will be shown in “loadmap”. For result files with load increments greater than 1, they will be listed in both Static and Transient type of loading.
- Evaluate
- The following enhancements are available in the Evaluate tool:
- Safety Factor output: Options available to request safety factor output for constant "Mean" or "Stress Ratio".
- Target Life: When Safety Factor output is requested, Target Life can be input.
- Results Context
- The following enhancements are available in the results context:
- The result contour legend is automatically reversed for Life, Safety Factor, and FOS output.
- Rainflow data can be exported for SN and EN analyses (including Random and Sine Sweep) for the queried element.
- Right-click options available with legend context menu.
Resolved Issues
- LS-DYNA results (D3PLOT)
- Radioss results (H3D)
- LS-DYNA results (D3PLOT)
- Radioss results (H3D)
- Abaqus (ODB)
- ANSYS (RST)
Known Issues
- When multiple result files are loaded (with the same geometry), the loadcases (loadstep) can’t have identical names. The workaround is to create derived a loadcase with a different name using the Loadcase tool.
- Derived loadcases are not supported with Random loading.
- Model Superposition: A known issue exists where parts selected for analysis of large models may take a longer time. This will be addressed in the upcoming release schedules.