49 citations · 324 across the 34 of their papers we have counts for
15 papers · 1 filter
Structure Preservation for the Deep Neural Network Multigrid Solver
Nils Margenberg, Christian Lessig, Thomas Richter
The simulation of partial differential equations is a central subject of numerical analysis and an indispensable tool in science, engineering and related fields. Existing approache…
Falling balls in a viscous fluid with contact: Comparing numerical simulations with experimental data
Henry von Wahl, Thomas Richter, Stefan Frei +1
We evaluate a number of different finite element approaches for fluid-structure (contact) interaction problems against data from physical experiments. For this we take the data fro…
A finite element / neural network framework for modeling suspensions of non-spherical particles. Concepts and medical applications
Martyna Minakowska, Thomas Richter, Sebastian Sager
An accurate prediction of the translational and rotational motion of particles suspended in a fluid is only possible if a complete set of correlations for the force coefficients of…
Settling of spherical particles in the transitional regime
Thomas Hagemeier, Dominique Thévenin, Thomas Richter
The settling process and wall impact of large spherical particles in a stagnant, highly viscous fluid has been observed by means of high-speed shadow imaging. The particles include…
A neural network multigrid solver for the Navier-Stokes equations
Nils Margenberg, Dirk Hartmann, Christian Lessig +1
We present the deep neural network multigrid solver (DNN-MG) that we develop for the instationary Navier-Stokes equations. DNN-MG improves computational efficiency using a judiciou…
A Low-rank Method for Parameter-dependent Fluid-structure Interaction Discretizations With Hyperelasticity
Peter Benner, Thomas Richter, Roman Weinhandl
Fluid-structure interaction models are used to study how a material interacts with different fluids at different Reynolds numbers. Examining the same model not only for different f…
Adaptive time-step control for a monolithic multirate scheme coupling the heat and wave equation
Martyna Soszynska, Thomas Richter
We consider the dynamics of a parabolic and a hyperbolic equation coupled on a common interface and develop time-stepping schemes that can use different time-step sizes for each of…
A locally modified second-order finite element method for interface problems and its implementation in 2 dimensions
Stefan Frei, Gozel Judakova, Thomas Richter
The locally modified finite element method, which is introduced in [Frei, Richter: SINUM 52(2014), p. 2315-2334], is a simple fitted finite element method that is able to resolve w…
Axisymmetric Stokes flow due to a point-force singularity acting between two coaxially positioned rigid no-slip disks
Abdallah Daddi-Moussa-Ider, Alexander Sprenger, Yacine Amarouchene +5
We investigate theoretically on the basis of the steady Stokes equations for a viscous incompressible fluid the flow induced by a Stokeslet located on the centre axis of two coaxia…
Error estimation and adaptivity for differential equations with multiple scales in time
Leopold Lautsch, Thomas Richter
We consider systems of ordinary differential equations with multiple scales in time. In general, we are interested in the long time horizon of a slow variable that is coupled to so…
A Newton multigrid framework for optimal control of fluid-structure interactions
L. Failer, T. Richter
In this paper we consider optimal control of nonlinear time-dependent fluid structure interactions. To determine a time-dependent control variable a BFGS algorithm is used, whereby…
On the Impact of Fluid Structure Interaction in Blood Flow Simulations: Stenotic Coronary Artery Benchmark
Lukas Failer, Piotr Minakowski, Thomas Richter
We study the impact of using fluid-structure interactions (FSI) to simulate blood flow in a large stenosed artery. We compare typical flow configurations using Navier-Stokes in a r…
The candy wrapper problem -- a temporal multiscale approach for pde/pde systems
Thomas Richter, Jeremi Mizerski
We describe a temporal multiscale approach for the simulation of long-term processes with short-term influences involving partial differential equations. The specific problem under…
An unfitted Eulerian finite element method for the time-dependent Stokes problem on moving domains
Henry von Wahl, Thomas Richter, Christoph Lehrenfeld
We analyse a Eulerian Finite Element method, combining a Eulerian time-stepping scheme applied to the time-dependent Stokes equations using the CutFEM approach with inf-sup stable…
A goal oriented error estimator and mesh adaptivity for sea ice simulations
Carolin Mehlmann, Thomas Richter
For the first time we introduce an error estimator for the numerical approximation of the equations describing the dynamics of sea ice. The idea of the estimator is to identify dif…