Recent content by SaeidII

Hello, Missil, I am using solid to solid contact. I tried soft method and pinball and the results are similar. Greg, Because the solids are cylinders with different diameters; if they don't slide freely when having radial deformation there will still be forces in the contact plane. I checked the...

Hello Sampurna, for Explicit Analysis there must be no difference, since ansys uses ls-dyna code for explicit analysis. Can you please tell more?

Hello, I have two solids with different Poisson ratio pushed against each other. Model is analyzed by ls-dyna and I have huge shear stresses on the surfaces of the solids. Contact friction is set to zero; Any idea if this is supposed to be like this? I'd appreciate for your comments.

Hello, I need to implement the strain rate effect on a material model using load curve table. The example for material model 72r3 in ls-dyna manual has used 1/milliseconds for strain rate unit; And now I am confused shall I input strain rate in 1/ms regardless of time unit I am using in the...

Update: adding param,dyconignore*,2 to the bulk file dramatically reduced these stresses; Default value of dyconignore is zero which means initial penetration elimination is enable; But why does it make anything worse?!

Attached image describes the problem better: http://files.engineering.com/getfile.aspx?folder=2ff0636e-363a-42dd-889f-539c9491d009&file=initial_contact.png

Hi, using nastran explicit analysis (sol700) I have noticed if two solids are too close to each other or touching each other; contact stress will be produced on faces of those solids and propagate into model. Since contact thickness offset of solids is zero by default and initial penetration...

Hi, I want fine mesh on the end of a cylindrical rod and coarser mesh on the rest. I could not figure it out how to do that. I tried slicing it using imprint but the created mesh points can't be equivalenced. Any clues? Thank you.

Hi, I have several 1D beams embedded in a solid. I want them to work together e.g. share nodes together. Equivalence option is not giving me the result I want. Do you think there is a way to accomplish this goal? Thank you.

I finally figured it out, The touching solids had different mesh types and probably that was the cause of wrong results.

Hello, I am having huge unwanted stresses in two solid that are only touching each other. The stresses exist from second time step afterward. With enabling ignore initial penetration(DYCONIGNORE), I was not expecting this behaviour. I have already checked the model and there is no penetration...

Hi, Is it possible to set PATH=3 in Executive Control Section before analyzing the model? I have already tried direct text input in that section but this command should be added after SOL command like: SOL 700 PATH=3 I did not find any build in option to set this either. If you know how to do...

Hello, There is an Erosion material in Patran(materials>create>erosion) in order to implement MATDERO of sol700. MATDERO is not supposed to define a material model but supplements another material model. After defining it I found no option to assign it to another material model I have already...

Hope this will help. There are some information on this in nastran 2001 release guide page 66 and 2004 release guide page 100. good luck.

I could not figure it out how to create materials that are supported by Nastran Explicit NL Analysis in Patran; Documentation says the following materials are not supported in patran: Unsupported Materials in Patran Preference All the material models listed above are supported with the...