Learning Forum

[Muhammad Hamza Arshad Khan]

Hello,

I have mapped anisotropic properties on a bone geometry with another software and then imported those files in ansys with the mesh. I have given a command script which assigns three properties (density, youngs modulus and poissons ratio) to different elements of the mesh. As you can see it only defines the elastic region of the bone material but I want to model its plastic behavior too. I tried using simple bilinear model in the engineering data but when I plot the plastic strain I dont get any results (even if the stress is greater then yield strength). Maybe since the command script with material properties are executed just before the solution point so it overrides all the data defined in the engineering data. Could anyone explain how can assign a plastic material model in my case , maybe with a command script or something. Thanks in advance!

 

[Ashish Khemka]

Hi,

Can you define plasticity in the command script?

You can open the solver files directory and open the ds.dat file. From there you will find the commands to define biinear model and then use the same.

Regards,

Ashish Khemka

[Muhammad Hamza Arshad Khan]

Hi ashish, thanks for your reply .

I managed to get a plastic strain after using the plastic model in command script. However it doesnot define the plastic model to all elements. My geometry has different values of elastic modulus for different elements so they have different material IDs .But when I define the plastic model it only shows surface elements of the bone selected.

As it can be seen that the plasticity is not defined for the whole body, it is only defined over some surface elements. How can i define plasticity over the whole body or some specific elements.

This is how I defined the elastic properties in my command script

Can i define the plastic properties like this with an apdl command?

 

[Ashish Khemka]

Hi,

You can create a named selection of theelements of ineterest and then may try using the emodif command:

/Prep7 cmsel,s,bones ! named selection for region of interest

! Define material properties using MP commands

emodif,all,mat,100 ! Here, 100 represents the material number

allsel

/solu

Regards,

Ashish Khemka

 

 

 

[Muhammad Hamza Arshad Khan]

Hi ashish , thanks for your reply 

I managed to assign different plastic material models to all the different material IDs using TB command.

This thread helped me alot.

I have a question , Is there any source available where I can look up ansys apdl commands or the full definition of different parameters in a apdl command separated by commas.

Once again thanks!

 

[Ashish Khemka]

Hi,

Thanks for the update. Please refer to the following link:

https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v241/en/ans_cmd/Hlp_C_CmdTOC.html

How to access the ANSYS Online Help

Regards,

Ashish Khemka