General Mechanical

General Mechanical

Topics relate to Mechanical Enterprise, Motion, Additive Print and more

Cohesive zone model based Contact pair w/ overconstraint

    • cheng089413

      Hello community,

      Did anyone know whether this note about the contact would be an issue?

      I created several pure penalty bonded contacts with Cohesize zone model. The target and contact are with same material. I found the notes in the solution output for each of the bonded contact. Some of them have the warning message as below.

       *** NOTE ***                            CP =      35.582   TIME= 14:19:13
       Symmetric Deformable- deformable contact pair identified by real       
       constant set 272 and contact element type 272 has been set up.  The    
       companion pair has real constant set ID 273.  Both pairs should have   
       the same behavior.                                                     
       *WARNING*: ANSYS has found the contact pairs have similar mesh patterns
       which can cause overconstraint.  ANSYS will deactivate the current     
       pair and keep its companion pair.                                      
       Contact algorithm: Penalty method
       Contact detection at: Gauss integration point
       Contact stiffness factor FKN                  1.0000   
       The resulting initial contact stiffness      0.13257E+13
       Default penetration tolerance factor FTOLN   0.10000   
       The resulting penetration tolerance          0.13341E-02
       Default opening contact stiffness OPSF will be used.
       Default tangent stiffness factor FKT          1.0000   
       Default elastic slip factor SLTOL            0.50000E-02
       The resulting elastic slip tolerance         0.46082E-04
       Update contact stiffness at each iteration
       Default Max. friction stress TAUMAX          0.10000E+21
       Average contact surface length               0.92163E-02
       Average contact pair depth                   0.13341E-01
       Average target surface length                0.73704E-02
       Default pinball region factor PINB           0.25000   
       The resulting pinball region                 0.33354E-02
       Initial penetration/gap is excluded.
       Bonded contact (always) with debonding is defined.
       *** NOTE ***                            CP =      35.582   TIME= 14:19:13
       Max.  Initial penetration 3.797587245E-13 was detected between contact 
       element 135148 and target element 135355.                              

      I have attached the settings of one of the bonded contact and all others are the same.

      Appreciate if someone can provide any advice on this. 


    • cheng089413

      Hi community, does anyone have any ideas about this? thank you!😉

    • Ashish Kumar
      Forum Moderator


      The warning message indicates that there are 2 pairs depicting the same behavior and Ansys is deactivating one of the pair which should be fine.



      Ashish Khemka

      • cheng089413

        Hello Ashish, thank you!

        I double checked the model and did not find any replicately defined contact pairs between same surface.

        What may cause this warning message? I am curious...

Viewing 2 reply threads
  • You must be logged in to reply to this topic.