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How to include point mass in explicit dynamics without error?

    • Tony6
      Subscriber

      I am simulating a car crash but i am only interested in the bumper behavior. This is why i have only modeled the bumper system and need to add a point mass to virtually include the mass of the vehicle. Without this, the impact would not be representative of an actual event due to inertial effects.

      I added a point mass in geometry and specific its mass and location but when i try to run the simulation i get the following error message:

      "Invalid object (Point Mass) for an Explicit analysis. If the object is not visible, please disable Environment Filtering to review and remove/suppress these objects from the Tree."


      I am surprised to see that explicit analysis does not support point mass? Is there a workaround? Same error is for distributed mass as well. Please how to fix this?

      Thank you!

    • Chris Quan
      Ansys Employee
      Are you using the recent versions of ANSYS? For examples, the versions after 2019R1?
      Point mass is available in Explicit Dynamics. You need to make sure the geometry where the point mass is scoped to has not been used in any other remote attachments such as remote boundary conditions, joints, springs, etc.

    • Tony6
      Subscriber
      I am using R18.2 which is available at my university. The geometry that the point mass is scoped to does not have other remote attachments
    • amarcon
      Subscriber
      thanks for your help, I was having the same problem.
      My explicit simulation worked when I applied the mass point by remote attachment to a random single surface, while it didn't work when I applied to a 4 distinct surfaces. The 4 surfaces have no other joints/remote BD conditions I can tell, but is there a way to verify?
    • Johanes Patrik
      Subscriber
      If i may know, how you defined point mass as representative as vehicle body. And which geometry do you choose to add point mass? Thank you
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