Issues with cohesive zone modelling

Fabian V.
Fabian V. Altair Community Member
edited October 2023 in Community Q&A

Hello,

I have some problems regarding cohesive zone elements in Optistruct (2019.1). While the Damage Model Method with interface elements as CIFHEX is working as expected, other methods do not seem to work.

How can you influence the orientation, element normal, of elements in Hyperworks? I need to specify the top and bottom surface, how can I achieve this?

Is node sharing required for CIFHEX elements or is it possible to define contact conditions?
Traction-Opening Curves Method based cohesive elements create an error message "Internal programming error in file "cohe_trac_disp.F" at location # 230". Is the implementation of these elements completed or still in the works?

Cohesive contacts create an error message "Syntax error(s) found in bulk data 'contact' card" while using the same parameters as a working Freeze or Sliding contact except with the mcohed cohesive data from the Damage Model Method. What might cause this error?

From the User guide Optistruct 2020 for contact based cohesive zone: "Currently only SMALL sliding, frictionless, N2S/S2S contact is supported for cohesive modelling." Does this imply that for cohesive contacts ONLY the seperation - normal forces create a degeneration and that shear is not regarded in this contact?

Regards.

Answers

  • Thomas Quenaon_21507
    Thomas Quenaon_21507 New Altair Community Member
    edited May 2021

    Hi Fabian V.,

    CZM method defined with contact is available in OptiStruct 2020, not in 2019. Are you able to upgrade your OptiStruct version ? (2021 version is the last available, 2021.1 should be released soon)

    BR-

    Thomas

     

  • Adriano A. Koga
    Adriano A. Koga
    Altair Employee
    edited May 2021

    Hi Fabian V.,

    CZM method defined with contact is available in OptiStruct 2020, not in 2019. Are you able to upgrade your OptiStruct version ? (2021 version is the last available, 2021.1 should be released soon)

    BR-

    Thomas

     

    2021.1 is already available! :)

  • Fabian V.
    Fabian V. Altair Community Member
    edited May 2021

    Thanks for your replies! I am afraid I will not be able to upgrade my Optistruct version at the moment. 

     

    Is the Traction-Opening Curves Method available in Optstruct 2019.1 or is this feature only available on newer versions?

  • Thomas Quenaon_21507
    Thomas Quenaon_21507 New Altair Community Member
    edited May 2021
    Fabian V. said:

    Thanks for your replies! I am afraid I will not be able to upgrade my Optistruct version at the moment. 

     

    Is the Traction-Opening Curves Method available in Optstruct 2019.1 or is this feature only available on newer versions?

    Yes for the Traction-Opening Curves Method, only a single layer of cohesive elements are allowed to model a particular adhesive or bonded interface. 

    Those cohesive elements (CIFHEX/CIFPEN) are available in OptiStruct 2019.1

     

    Attached you can find an example.

    BR-

    Thomas

     

  • Akhil_22546
    Akhil_22546 Altair Community Member
    edited October 2023

    Yes for the Traction-Opening Curves Method, only a single layer of cohesive elements are allowed to model a particular adhesive or bonded interface. 

    Those cohesive elements (CIFHEX/CIFPEN) are available in OptiStruct 2019.1

     

    Attached you can find an example.

    BR-

    Thomas

     

    Hello, 

    I have been looking for a way to model glued contact and I did manage to do it with the Contact based method using PCOHE but I cannot find the CIFHEX/CIFPEN elements anywhere. Could you please guide me through. I am using 2022.3 version.