ANSYS Workbench 14 Line Model Question
ANSYS Workbench 14 Line Model Question
(OP)
I have recently been learning how to use ANSYS Workbench 14. I have been working through the examples outlined in "Finite Element Simulations with ANSYS Workbench 14" by Huei-Huang Lee. I am now working on a 3D building frame that utilizes different cross sections. In DesignModeler I added all of my points, created lines from points (added frozen), created cross section profiles, assigned the cross section profiles to the appropriate lines, and then selected all bodies and formed a single part. I then open up the system in Mechanical and apply my loads, fix my end connects, generate a mesh, and go to solve. I get the following error:
"Solver pivot warnings have been encountered during the solution. This is usually a result of an ill conditioned matrix possibly due to unreasonable material properties, an under constrained model, or contact related issues. Check results carefully."
Please help!
Thanks,
Joshua
"Solver pivot warnings have been encountered during the solution. This is usually a result of an ill conditioned matrix possibly due to unreasonable material properties, an under constrained model, or contact related issues. Check results carefully."
Please help!
Thanks,
Joshua





RE: ANSYS Workbench 14 Line Model Question
If all of your bodies are in the same part, this is not a contact issue. Check your materials to verify that you didn't forget something. To see if your model is underconstrained, try running a modal analysis. 0-frequency modes (if you have some), will show you the rigid body motions allowed in your model, with that, you can set the missing BCs.
RE: ANSYS Workbench 14 Line Model Question
"You have performed a pre-stress modal analysis with large deflection effects turned off in the static analysis. For a more accurate modal solution, we recommed turning on large deflection effects."
I turned large deflection to "on" and reran the solution. I now have the following two errors/warnings:
"An internal solution magnitude limit was exceeded. Please check your environment for inappropriate load values or insufficient supports. Also check that your mesh has more than 1 element in at least 2 directions if solid brick elements are present."
and
"One or more of your branches is dependent on a linked branch that is setup to solve remotely. The remote solutions for the linked branches have been started. You will need to retrieve the results for those branches and submit the solve request again for the remaining branches."
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
Also, your model is not supposed to "act like a rigid body". A rigid body motion means your model is underconstrained. The modal analysis helps you see what conditions are missing. For example if you have a 0-freq mode with displacement in X-direction, it means you have no contrain in that direction. Thus here, I guess you have no constrains at all.
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
But when you have all your bodies and cross section created, select your bodies in the tree, right click > form new part, your different bodies will be put in the same part, which is kind of the same thing but allowing you to have different cross sections (and also different materials etc...).
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
Workbench doesn't apply BCs depending on the cross section, only depending on how you define them in mechanical.
Do all your bodies' extremities coincide with at least one other body ?
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
What you could try is to add bonded contacts where your bodies touch.
RE: ANSYS Workbench 14 Line Model Question
RE: ANSYS Workbench 14 Line Model Question
Maybe, if your model is not confidential, you could upload it, I could try to find some time to look at it next week.
RE: ANSYS Workbench 14 Line Model Question