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Constraint for variable in PDE- Mode
Posted Dec 6, 2013, 7:27 a.m. EST Parameters, Variables, & Functions, Studies & Solvers, Structural Mechanics Version 4.3b 0 Replies
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I'm trying to simulate fractures by using a phase field model.
The variables u and v describe the displacement of the body and s is the phase field variable that describes wheter the material is broken or not. At the beginning, s=1 (no fracture) at the end of the simulation s=0 (fracture) in some regions of the body.
To describe the irreversibility of the fracture I have to implement the following constraint: st<0
Equations:
div(sigma)=0 stress balance equation
st=M*(s*(epsilon:(C*epsilon))-Gc*((1-s)/2*a)+2*a*laplace(s))) phase field equation
Problem: I have tried to implement it via an global constraint but without any success.
What would be the best way to implement this inequality?
Hello Ricardo Blauwhoff
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