USF_Damage.f90
EnhancementFactor
SourceDamage
The first function changes the rheology of the damage ice by impacting the enhancement factor.
The second function is used to compute the source term of the advection-reaction solver.
The required keywords in the SIF file for this User Function are:
Constants Dev Tensile Strength Modifier = Real 0.05 ! standard deviation for the stress threshold distribution End Body Force 1 DGD Source = Variable Damage Real Procedure "ElmerIceUSF" "SourceDamage" End Material 1 Glen Enhancement Factor = Variable Damage Real Procedure "ElmerIceUSF" "EnhancementFactor" Damage Enhancement Factor = Real 2.00 ! damage enhancement factor Damage Parameter sigmath = Real 0.05 ! stress threshold for damage increase End
Additionnally, for output visualisation, the damage criterion Chi is saved as a variable named Chi, which need to be exported in a solver, such as :
Solver 3 Equation = Sij Procedure = "ElmerIceSolvers" "ComputeDevStress" [...] Exported Variable 1 = Stress[Sxx:1 Syy:1 Szz:1 Sxy:1 Syz:1 Sxz:1] Exported Variable 1 DOFs = 6 Exported Variable 2 = -dofs 1 "Chi" [...] End
A 3D example can be found in [ELMER_TRUNK]/elmerice/Tests/Damage
.
Krug, J., J. Weiss, O. Gagliardini and G. Durand, 2014. Combining damage and fracture mechanics to model calving, The Cryosphere, 8, 2101-2117, doi:10.5194/tc-8-2101-2014.