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Hyperman

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About Hyperman

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  1. I am not sure what you want to do. The shell elements of base surface should still be in the model after tetrameshing. Use View>Browser>Hypermesh>Mask to show/hide 2D or 3D elements. You can copy or move the triangular shell elements into another component with Organize Panel (shift+F11).
  2. Hi, use Geometry>edit>nodes>associate The Associate subpanel creates an association between the selected nodes and a selected piece of geometry. Nodes are projected to the geometry, provided the distance to the selected geometry is within the search tolerance. The tolerance is used to create a search sphere at each of the selected nodes. If the selected geometry is found within that search sphere, the node is projected to the closest point on the geometry. An association is made within the database between the nodes (and corresponding elements) and geometry, so any subsequent selection routines can reference either entity; for example, if creating a boundary condition (such as a force, pressure, or constraint) on the geometry, the boundary condition will be applied to the nodes and or elements upon export.
  3. There is a warning due to material properties: There are many errors due to bad element quality: I could remesh the model, but you would not learn how to do it yourself if I did it for you. I just corrected the worst elements so the model is able to run. You should remesh the model using the these tools: Geom>autocleanup to clean up the geometry 2D>automesh>QI optimize (F12) to mesh using quality criteria 2D>elem cleanup 2D>qualityindex tool>check elems>2D (F10) to check elements There are some great learning materials from Altair university- Practical Aspects of Finite Element Simulation is a good starting point. https://altairuniversity.com/free-ebooks-2/ Check the following Youtube channels: Altair University Altair India Student Contest ELEATION By Apoorv Bapat test 2_edit.hm test 1_edit.hm
  4. From free eBook: Simulation-Driven Design with Altair Inspire: The same applies whether a hole or a flat surface- partition the design space adjacent to the surfaces with loads and BCs and put those volumes into non-design space.
  5. Glad to help. the "0" in the 3rd column of the CTRIA3 definition indicates that at least some elements have no PIDs (property) assigned. Please check in HM if you have correct references from the comps (or elements) to the props. You have in HM two possibilities to reference the proper property to your CTRIA3 elements: 1) (recommended): Assign the property collector (PSHELL) to the component collector your CTRIA3 elements are in 2) Assign the property collector (PSHELL) directly to your CTRIA3 elements. Use Tools>Model Checker>Optistruct to find modeling errors. https://insider.altairhyperworks.com/wp-content/uploads/2017/09/T-T-1248-HyperMesh-Model-Checker.pdf
  6. Hi, applying loads and boundary conditions on design space is not recommended. https://altairuniversity.com/wp-content/uploads/2014/01/Washer.pdf https://altairuniversity.com/learning-hyperworks/tips-tricks/solidthinking-inspire/
  7. Hi, both models have the same issue: You need to add DTI UNITS card. Go to Control cards>DTI_UNITS> input the same unit system which you have used for modeling and run the analysis.
  8. Hi, Stress constraint is not recommended in the design concept stage: topology, topography and free-size optimization.  The stress constraint definition in a topology optimization is a global constraint and does not target local stress concentrations. These areas can be addressed subsequently through size, shape, and free shape optimization or a combination thereof. Artificial stress concentrations are filtered out during topology optimization with stress constraints. These include regions around rigid connections, concentrations due to hard geometric features such as corners, etc. Stress constraints for a partial domain of the structure are not allowed because they often create an ill-posed optimization problem since elimination of the partial domain would remove all stress constraints. Consequently, the global stress constraint applies to the entire model when active, including both design and non-design regions. Stress constraints may not work well in a model where there is a large differential in response values between design and non-design spaces. In these cases, it is recommended to modify the problem formulation to say, compliance based for example. It is not recommended to use the global stress constraint along with a mass/volume constraint. The constrained mass/volume may not allow the stress constraint to be satisfied. DRESP1-card stress constraint is used in subsequent design fine-tuning stage such as size, shape and free shape optimization.
  9. Hi, This is strange: base thickness is available only for PSHELL type (not PCOMPG), toggle to specify a non-zero value for the base thickness. A component’s total thickness is the same as the thickness given in its PSHELL card. The default base thickness is 0.0, but you can click the toggle to enter a different base thickness.
  10. Hi, you can model functionally graded thickness by assigning multiple properties with different shell thicknesses. If you already have the geometry then use mesh>create>midsurf mesh to create a midsurface mesh with a thickness from 3D geometry using the Midsurface Mesh tool.
  11. Hi, For each degree of freedom that you wish to constrain, click the checkbox that corresponds to it. The selected Dofs will be constrained. Dofs 1, 2, and 3 are x, y, and z translation degrees of freedom. Dofs 4, 5, and 6 are x, y, and z rotational degrees of freedom.
  12. This is strange- I am able to set up a type 7 contact interface without problems on my end. Which version do you use?
  13. @Skill.Leo0 Contacts with friction and hourglass energy are usually a source of negative error (energy dissipation) since they are not counted in the energy balance. The guidelines you mentioned are valid, but can not be generalized to all models (although the source of discrepancy has to be identified). From Radioss>Frequently Asked Questions>Results Checking: All else being equal, there should not be much difference in the results between brick or tetra mesh. Brick meshing is usually harder, especially if structured mesh of good quality is required, but it can be more computationally efficient on the other hand.
  14. Hi, this is because of the different contact interface definition: tetra model had Iform=2 brick model had Ifric=2
  15. Hi, there was no contact interface defined in your model. birdstrike_edit_0000.rad For more details refer to a similar example: RD-E: 4900 Bird Strike on Windshield
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