United States | 
Video Presentation of NEi Works
Composite FEA
A composite bicycle frame model made of 2D orthotropic carbon weave material is created. Loads are applied and a static analysis is performed using a laminate element made up of multiple plies at various ply angles. Results are presented using various graphic visualization methods and the use of several failure criteria are illustrated.
Features to Look for in FEA Software for Composite Analysis
Composite materials analysis imposes a number of requirements that are significantly different when compared to isotropic materials and FEA software used for composite analysis must
be designed to handle the anisotropic nature of composites and the failure mechanisms associated with their properties like
cracks, delaminations, and fiber failure. In addition, high quality FEA software should include features that make it easy
to use while providing the engineer with the power to get results
that are practical and truly valuable for application to real
world problems. NEi Nastran fills this need for composite designers with
a number of features in model creation, material definition, meshing, post processing, failure criteria, and data presentation.
- User friendly definition of material properties
- Definition of ply lay-up
- Easy orientation definition
- Outer mold line representation
- Post processing visualizations that pinpoints problem areas
- Failure Indices and Strength Ratio
- Import 3D CAD models
- Sensitivity and configuration trade off studies
- Progressive Ply Failure Analysis (PPFA™)
- User friendly definition of material properties. Clear, easy input of strength and stiffness terms with access to material libraries.
- Definition of ply lay-up. Stacking sequences can be quickly and easily entered into a table, and symmetry can be used to reduce entries. Modification and changes are easily made and the chance of error is greatly reduced.
- Easy orientation definition. Curved surfaces can complicate the orientation of fibers. NEi Nastran can project a cylindrical or spherical coordinate system onto a structure to get good representation of ply orientation. Advanced application can carry out draping analysis with Simulayt if this degree of fidelity is required.
- Outer mold line representation.
- Post processing visualizations that pinpoints problem areas. Enormous amounts of data can be involved in multi lay-up and multi ply structures. NEi Nastran provides a logical path from stress analysis of a structure to Failure Index results that can isolate problems and pinpoint them to definite regions on specific plies.
- Failure Indices and Strength Ratio. NEi Nastran
supports all the major composite failure analysis indices Tsai-Wu,
Hill, Hoffman. Plus NEi Nastran
includes the most modern forms of Puck and NASA Langley LARC02.
In addition, the Strength Ratio is available for easy linear scaling
and qualitative analysis.
NASA Langley has developed LARC02, a set of first-ply-failure criteria which have shown to be accurate and physically consistent. It is well suited for design purposes because it balances accuracy, material characterization requirements, computational effort, and ease of results interpretation.
Advanced Failure Criteria for Composites
LaRC02 Set of Criteria- Developed by NASA
- First-ply-failure
- Physically based
- Hashin, Puck approach
- No additional material properties required compared to Tsai-Wu
- Failure mode taken into account
- Extensive validation (WWFE)
Stability Index Output for Sandwich Structures
Theory based on Facesheet Wrinkling in Sandwich Structures, NASA-CR-1999-208994, 1999Honeycomb Sandwich Material Properties
MaterialModulus of Elasticity (msi)Tensile Limit (ksi)Compression Limit (ksi)Shear Limit (ksi)Aluminum Face Sheets10.035.035.023.0Honeycomb Core0.10.10.30.2Bonding Material---0.1
For more information see "Finite Element Implementation of Advanced Failure Criteria for Composites".
- 3D CAD Models. Femap imports models from all major CAD systems. For SolidWorks users, NEi Works is embedded, completely eliminating the need to import files.
- Sensitivity and Configuration Trade Off Studies. NEi Nastran Editor feature is perfect for composite analysis because it provides an easy inexpensive way to do sensitivity and configuration trade off studies.
- Features tabbed windows to give immediate access to all input and output files
- Field markers make manual editing simple and increase productivity dramatically
- Complete online documentation and context sensitive help
- Permits batch queuing of jobs for sensitivity and configuration trade studies
- Special real time controls allow changing solution parameters while running
- Real time 2D xy-plotting and 3D deformed shape and contour plotting
- Progressive Ply Failure Analysis (PPFA™) allows engineers to examine composite structural behavior beyond first ply failure. Reduce weight and material costs while saving time in analysis by efficiently analyzing residual strength, local damage effects, temperature effects, post-FPF (First Ply Failure) events, separation, ultimate failure, design modifications, and ultimate strength with PPFA.
Flyers
Composites
Analysis Flyer
Progressive Ply Failure Analysis (PPFA™)
Flyer
Product Demonstration Options and Information
Media Coverage
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Oct 2009 |
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NEi Software and Firehole Technologies Partner to Deliver Composites Analysis to NEi Nastran |
Jan 2008 |
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Composite plates with two concentric layups under compression |