Learning Forum

[Mohankumar]

Hello,

I want to measure the rotation of vertebra. Here is what I did:

(1) Fixed lower surface of the lower body. Applied moment (10,000 N.mm) on top surface of the top body in Z axis. (2) Checked whether the contact regions between disc, top and bottom body are intact. (3) Solver type: Direct, Contact type: Bonded. (4) Selected Remote Point and Flexible Rotation Probe (Z axis).

After running the simulation, results look unrealistic and got warning message.

Top body rotated beyond the obstruction provided by lower body. Looking as if it penetrated into the lower body. Hence it is measured as 4.9971 degrees. Which is not acceptable. Normal range is 1.5 to 2.5 degrees only. Warning message: "One or more MPC contact regions or remote BC may have conflicts with applied BC"

How to solve this?

 

Thanks in advance.

[peteroznewman]

Hello Mohankumar,

I assume between the lower body and the top body, which are bones, is the disk body. I also assume that the Bonded contact shown is each bone to the disk.

One way to prevent the penetration between the bones that you drew the rectangle around is to add Frictional contact between those faces. Bodies can pass through each other by default. You have to add contact when you don't want that to happen.

Regards,

Peter

 

[Sandeep Medikonda]

Hi Mohankumar,

  Please see some of the guidelines listed in this section of the manual that talks about how to deal with penetration problems.

P.S: Please see how to access ANSYS Help here.

Regards,

Sandeep

[Mohankumar]

Thank you Mr. Peter. Will try your suggestion.

[Mohankumar]

Mr. Sandeep,

 

We have Ansys 18 only and moreover, I couldn't able to log in into Ansys Help. But I have an account in Ansys Customer Portal. Is their any other way to see the guidelines which you mentioned?

 

Regards.

 

 

[peteroznewman]

 Hi Mohankumar,

You can open ANSYS Help if you have the program open by using the Help Menu. One of the links Sandeep is pointing to can be found in the ANSYS 18 system at this location:

You get to that by navigating the menu tree on the left side of the Help window.

Regards,

Peter

[Sandeep Medikonda]

Mohan,

  Please see if this workaround suggested by peter helps? 

Regards,

Sandeep

[peteroznewman]

 Sandeep,

That workaround only works if the computer has ANSYS Student 19.1 installed.

Regards,

Peter