The next seminar “Modelling of materials – theory, model reduction and efficient numerical methods” will take place next Wednesday (March 31, 2021) from 9:00 till 10:00. The talk will be given by Pablo Alexei Gazca Orozco. Please see the details below.

Speaker: **Pablo Alexei Gazca Orozco**

Title: **A semismooth Newton method for implicitly constituted flow**

Abstract: We propose a semismooth Newton method for non-Newtonian models of incompressible flow where the constitutive relation between the shear stress and the symmetric velocity gradient is given implicitly; as a motivating example we consider the Bingham model for viscoplastic flow. The proposed method avoids the use of variational inequalities and is based on a particularly simple regularisation introduced recently by Bulíček et al., for which the (weak) convergence of the approximate stresses is known to hold. The system is analysed at the function space level and results in mesh-independent behaviour of the nonlinear iterations.