110 citations · 663 across the 36 of their papers we have counts for
36 papers
Reconstructing effective ultrasound transducer models via distributed source inversion
Tim Bürchner, Simon Schmid, Ernst Rank +2
Accurate modeling of ultrasound wave propagation is essential for high-fidelity simulation and imaging in ultrasonic testing. A primary challenge lies in characterizing the excitat…
Generalized eigenvalue stabilization for immersed explicit dynamics
Tim Bürchner, Lars Radtke, Sascha Eisenträger +4
Explicit time integration for immersed finite element discretizations severely suffers from the influence of poorly cut elements. In this contribution, we propose a generalized eig…
On the efficiency of explicit and semi-explicit immersed boundary finite element methods for wave propagation problems
Tim Bürchner, Lars Radtke, Philipp Kopp +3
Immersed boundary methods have attracted substantial interest in the last decades due to their potential for computations involving complex geometries. Often these cannot be effici…
Quantitative Comparison of the Total Focusing Method, Reverse Time Migration, and Full Waveform Inversion for Ultrasonic Imaging
Tim Bürchner, Simon Schmid, Lukas Bergbreiter +3
Phased array ultrasound is a widely used technique in non-destructive testing. Using piezoelectric elements as both sources and receivers provides a significant gain in information…
Implicit-Explicit Time Integration for the Immersed Wave Equation
Christian Faßbender, Tim Bürchner, Philipp Kopp +2
Immersed boundary methods simplify mesh generation by embedding the domain of interest into an extended domain that is easy to mesh, introducing the challenge of dealing with cells…
Isogeometric Multi-Resolution Full Waveform Inversion based on the Finite Cell Method
Tim Bürchner, Philipp Kopp, Stefan Kollmannsberger +1
Full waveform inversion (FWI) is an iterative identification process that serves to minimize the misfit of model-based simulated and experimentally measured wave field data, with t…
Two-scale analysis and design of spaceframes with complex additive manufactured nodes
Oguz Oztoprak, Alexander Paolini, Pierluigi D'Acunto +2
The advancements in additive manufacturing (AM) technology have allowed for the production of geometrically complex parts with customizable designs. This versatility benefits large…
Immersed boundary parametrizations for full waveform inversion
Tim Bürchner, Philipp Kopp, Stefan Kollmannsberger +1
Full Waveform Inversion (FWI) is a successful and well-established inverse method for reconstructing material models from measured wave signals. In the field of seismic exploration…
Predicting Fracture in the Proximal Humerus using Phase Field Models
L. Hug, G. Dahan, S. Kollmannsberger +2
Proximal humerus impacted fractures are of clinical concern in the elderly population. Prediction of such fractures by CT-based finite element methods encounters several major obst…
Space-time hp finite elements for heat evolution in laser-based additive manufacturing
Philipp Kopp, Victor Calo, Ernst Rank +1
The direct numerical simulation of metal additive manufacturing processes such as laser powder bed fusion is challenging due to the vast differences in spatial and temporal scales.…
The Finite Cell Method with Least Squares Stabilized Nitsche Boundary Conditions
Karl Larsson, Stefan Kollmannsberger, Ernst Rank +1
We apply the recently developed least squares stabilized symmetric Nitsche method for enforcement of Dirichlet boundary conditions to the finite cell method. The least squares stab…
Quantitative reconstruction of defects in multi-layered bonded composites using fully convolutional network-based ultrasonic inversion
Jing Rao, Fangshu Yang, Huadong Mo +2
Ultrasonic methods have great potential applications to detect and characterize defects in multi-layered bonded composites. However, it remains challenging to quantitatively recons…
Efficient multi-level hp-finite elements in arbitrary dimensions
Philipp Kopp, Ernst Rank, Victor M. Calo +1
We present an efficient algorithmic framework for constructing multi-level hp-bases that uses a data-oriented approach that easily extends to any number of dimensions and provides…
Uncertainty quantification of microstructure variability and mechanical behaviour of additively manufactured lattice structures
Nina Korshunova, Iason Papaioannou, Stefan Kollmannsberger +2
Process-induced defects are the leading cause of discrepancies between as-designed and as-manufactured additive manufacturing (AM) product behavior. Especially for metal lattices,…
Bending behavior of additively manufactured lattice structures: numerical characterization and experimental validation
Nina Korshunova, Gianluca Alaimo, Seyyed Bahram Hosseini +6
Selective Laser Melting (SLM) technology has undergone significant development in the past years providing unique flexibility for the fabrication of complex metamaterials such as o…
Image-based numerical characterization and experimental validation of tensile behavior of octet-truss lattice structures
Nina Korshunova, Gianluca Alaimo, Seyyed Bahram Hosseini +6
The production of lightweight metal lattice structures has received much attention due to the recent developments in additive manufacturing (AM). The design flexibility comes, howe…
Hierarchical multigrid approaches for the finite cell method on uniform and multi-level hp-refined grids
John Jomo, Oguz Oztoprak, Frits de Prenter +3
This contribution presents a hierarchical multigrid approach for the solution of large-scale finite cell problems on both uniform grids and multi-level hp-discretizations. The prop…
Finite Cell Method for functionally graded materials based on V-models and homogenized microstructures
Benjamin Wassermann, Nina Korshunova, Stefan Kollmannsberger +2
This paper proposes an extension of the finite cell method (FCM) to V-rep models, a novel geometric framework for volumetric representations. This combination of an embedded domain…
A 3D benchmark problem for crack propagation in brittle fracture
Lisa Hug, Stefan Kollmannsberger, Zohar Yosibash +1
We propose a full 3D benchmark problem for brittle fracture based on experiments as well as a validation in the context of phase-field models. The example consists of a series of f…
Direct structural analysis of domains defined by point clouds
László Kudela, Stefan Kollmannsberger, Umut Almac +1
This contribution presents a method that aims at the numerical analysis of solids represented by oriented point clouds. The proposed approach is based on the Finite Cell Method, a…
Integrating CAD and Numerical Analysis: 'Dirty Geometry' handling using the Finite Cell Method
Benjamin Wassermann, Stefan Kollmannsberger, Shuohui Yin +2
This paper proposes a computational methodology for the integration of Computer Aided Design (CAD) and the Finite Cell Method (FCM) for models with "dirty geometries". FCM, being a…
From geometric design to numerical analysis: A direct approach using the Finite Cell Method on Constructive Solid Geometry
Benjamin Wassermann, Stefan Kollmannsberger, Tino Bog +1
During the last ten years, increasing efforts were made to improve and simplify the process from Computer Aided Design (CAD) modeling to a numerical simulation. It has been shown t…
A design-through-analysis approach using the Finite Cell Method (ECCOMAS Congress 2016)
Benjamin Wassermann, Tino Bog, Stefan Kollmannsberger +1
Modern 3D Computer-Aided-Design (CAD) systems use mainly two types of geometric models. Classically, objects are defined by a Boundary Representation (B-Rep), where only the object…
Residual stresses in metal deposition modeling: discretizations of higher order
Ali Özcan, Stefan Kollmannsberger, John N. Jomo +1
This article addresses the research question if and how the finite cell method, an embedded domain finite element method of high order, may be used in the simulation of metal depos…