Jump to content

Rahul R

  • Content Count

  • Joined

  • Last visited

  • Days Won


Everything posted by Rahul R

  1. Please refer attached document for nonlinear transient analysis setup. Nonlinear Analysis Setup.pdf
  2. We dont have detailed explaination for 3d mesh types with application.What type of 3d tetra mesh you are ineterested?
  3. Do you want geometry mappable for Hex meshing or Midsufacing complex parts?Please share some more information
  4. You can also simulate thermal analysis with Altair OptiStruct solver.Please use below link to download free ebook on thermal analysis using OptiStruct. https://altairuniversity.com/free-ebook-thermal-analysis-with-optistruct/
  5. Please refer attached document for virtual fluid mass. Virtual Fluid Mass.zip
  6. Since the analysis is converged successfully you can ignore information 2406.To post process displacement and acceleration in Hyperview request output in op2 or H3d format.
  7. Please share the fem file to take a quuick look.
  8. This could be a modeling issue (massless mechanism) due to the connection of CROD and SOLID elements. CROD has axial and torsional stiffness, and solid has only 3 translational stiffness. As a workaround, create a layer of shell elements on top of the solids, so the nodes connecting to CROD have rotational stiffness.
  9. Please check Mesh pull down : Fuse option
  10. It seems you are running older version of OptiStruct version 2017.2.1.This feature was originally supported for direct method in OptiStruct 2017.2. I see you are running modal method which is suppported for version 2017.2.2 and higher.Latest version of OptiStruct is 2019 .
  11. Shared out file also contains 3 warnings. How many loadstep you have & any specific reason for having FREQ1,DISP & ACCEL output?
  12. In the above shared tutorial, step 36 covers how to overcome error 5826.If possible please share the .out file of the run.
  13. Rahul R


    Could you share the .fem file using ftin link available in my signature.
  14. Please refer attached example and tutorial for acoustic acoustic infinite elements. Infinite_Elements.zip
  15. Please try with Param,inrel-2 & remove the SUPORT1 entry from load step or from the model.
  16. If the solver reports excessive mesh distortion, consider the following reasons: Excessive or unrealistic loading Over-constrained FE model Inconsistent unit system between model, material and/or loading that lead to excessive deformation Reviewing the last non-converged iteration in HyperView will help Please refer to attached model from OptiStruct example guide. OS-E 0195 Compression of Helical Springs usingSelf-Contact.pdf mola_Self_contact_v2_SPCF.fem
  17. Dear Professionals, I am working on Inertia Relief Analysis. I am working on a vrtical beam and when I want to analyze it as inertia relief in case of applying a force on it, I face an Error which says : """" ERROR 798*** The maximum number of support d.o.f. is six. support1 set id=1660 number of support d.o.f=2094132000"""" my model is a vertical beam with Support 1 at both ends and a axial force in the center at x direction. please guide me what is wrong with my model. I would really appreciate your help in advance. MS Yousefi
  18. Could you share some more info related to your requirements?
  19. I tested this with one simpe model in latest 2019.2 version and it works fine.
  20. Please try exporting in .Stl format.
  21. OptiStruct solves nonlinear set of equations with an implicit solution technique OptiStruct uses the incremental-iterative procedure based on Newton’s method The applied load is broken down into small increments For each of the small increments of load an approximate solution is obtained Several iterations may be required to obtain a sufficiently accurate approximate solution OptiStruct checks for convergence on three fronts U,P, and W (Displacement, Load and Work) Measures error in the nonlinear solution against a predetermined tolerance level The default error tolerances for the convergence criteria are 0.001 for displacement ,load & 1.0E-7 for work/strain It is not generally recommended to change the default values. However, varying the tolerances or excluding one or more criteria may affect the result accuracy Nonlinear expert system PARAM, EXPERTNL, AUTO (default)/YES/CNTSTB/NO The expert system monitors the convergence of nonlinear processes and tries to improve the convergence for poorly converging cases “YES” activates an ‘expert system’ that aids in the convergence. Possible actions like performing additional iterations, under-relaxation, automatic adjustment of the load increment, backing off to the last converged solution and retrying. May lead to a large number of nonlinear iterations. “AUTO” activates a ‘light’ version of the expert system which facilitates converging nonlinear process in reasonably close to minimum number of iterations. CNTSTB” introduces temporary stabilization on contact interfaces to improve nonlinear convergence
  22. Rahul R


    Card edit option would help you to assign CAABSF eleements.
  23. Rahul R


    I guess you have solid elements in your model and while meshing you would have used shell element (CTRIA) for solid element (Ctetra)creation.Please delete CTRIA elements and run again. Delete:Element by config:CTRIA3:select entity and delete
  24. "Strange" behaviors in HW are usually due to corruption of the session files. Deleting the session files should restore HW to their original state.
  • Create New...