Hi all,
I’m a biomedical engineering student and I’m trying to create a FEM simulation in SimScale with Mooney-Rivlin Hyperelastic model based on this scientific paper (Finite element simulation of human trachea: Normal vs. surgically treated and scaffold implanted cases - ScienceDirect).
What I want to do is simulate a displacement of the trachea structure when pressure on the trachea’s inner surface is applied. I’ve selected “Hyperelastic” in Material Behavior and Mooney-Rivlin in Hyperlastic Model.
Now I need to define the D1, C01 and C10 parameters. I’ve some problems to identify the exact parameters on the paper i posted above.
I suppose that the C01 and C10 coefficient are exactly the a1 and a2 parameters that i found in the paper:
Is it right?
Furthermore, I cannot understand how, starting from these coefficients, I have to calculate the parameter D1. I tried to follow the instructions in (Hyperelastic Materials | Simulation Setup | SimScale) but I get a negative value of D1 and it is not accepted by SimScale. Could anyone help me?
Thank you very much
Best
Luca
The suggestion given in the documentation page to compute the D1 parameter from the C01 and C10 coefficients should give you an initial guess for the parameter:
$$ D_1 = \frac{1 - 2\nu}{C_{01} + C_{10}} $$
For this types of materials, which are almost incompressible, $$ \nu $$ is close to 0.5, say something like 0.4995.
I tried and with your values, your D1 will be around 1e-4. If you simulation does not work, you can try using a lower value of around 1e-6 and test if this works.
Hi @ggiraldof ggiraldof, thank you very much for your suggestion!
I suppose that my value (a1 and a2) are expressed in MPa, is it correct?
Ok for the D1 parameter. I will try to run with 1e-4 and, if simulation does not work, I will try with 1e-6. Thank you
Luca
