The proof of Γ-convergence builds the base of the well-known Ambrosio–Tortorelli functional leading to an energy functional for quasi-static phase-field fracture problems. Three parameters in a monolithic quasi-static phase-field fracture model are very relevant for the quality of the results: the length-scale ε, the regularization parameter κ to avoid ill-posedness of the system and the discretization parameter h. The work on hand presents numerical results considering a pressure-driven cavity in 2d with two quantities of interest, the crack opening displacement and the total crack volume. The focus will be to discuss the assumptions of Γ-convergence which demand: h=o(κ) and κ=o(ε) and ε→0. An error analysis of the chosen quantities of interest allows to identify a proper setting for the three mentioned model parameters.
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