Learning Forum

[OmidNazeri1997]

Hi everyone.

I need to use the 5 parameter Mooney-Rivlin model to simulate the hyper-elastic behavior of the human ACL. I've found a related article, which describes the model constants. Here is a picture indicating the table of coefficients:  https://drive.google.com/file/d/1s2rwXOtdA8km24B52031RqN7wNZLEguU/view?usp=sharing

I have 2 questions:

1) Which value should i choose for the D1 (incompressibility) constant? Could (D1=0) be a proper value for ligaments or something near zero?

2) How can i enter the strain rate value for the constants? there is no place inside the engineering data module to enter this parameter.

Thank you in advance for any help.

[peteroznewman]

I inserted the image that is linked to above.

[OmidNazeri1997]

Hi Peter, Thanks.?

[OmidNazeri1997]

Hi there. I Considered using (D1 = 0) for this material model, but i face errors (convergene errors, an internal solution magnitude was exceeded errors and etc.) at the solution status. I really need help and i will share the details and screenshots if needed. please help me! ?

[bhagwantP]

Hello OmidNazeri1997,

There is one more discussion in this context. Please do check out if it helps to you:

Mooney-Rivlin Models (ansys.com)

8.5. Modeling Material Nonlinearities (ansys.com)

Thanks