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arXiv · 2006.16566

Adaptive and Pressure-Robust Discretization of Incompressible Pressure-Driven Phase-Field Fracture

Seshadri Basava·Katrin Mang·Mirjam Walloth·Thomas Wick·Winnifried Wollner
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Abstract

In this work, we consider pressurized phase-field fracture problems in nearly and fully incompressible materials. To this end, a mixed form for the solid equations is proposed. To enhance the accuracy of the spatial discretization, a residual-type error estimator is developed. Our algorithmic advancements are substantiated with several numerical tests that are inspired from benchmark configurations. Therein, a primal-based formulation is compared to our newly developed mixed phase-field fracture method for Poisson ratios approaching $\nu \to 0.5$. Finally, for $\nu = 0.5$, we compare the numerical results of the mixed formulation with a pressure robust modification.

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Seshadri Basava, Katrin Mang, Mirjam Walloth, Thomas Wick, Winnifried Wollner. 2020-06-30. Adaptive and Pressure-Robust Discretization of Incompressible Pressure-Driven Phase-Field Fracture. https://doi.org/10.1007/978-3-030-92672-4_8

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