Unser InstitutTeam
Peter Wriggers

Prof. em. Dr.-Ing. habil. Dr. h.c. mult. Dr.-Ing. E.h. Peter Wriggers

Prof. em. Dr.-Ing. habil. Dr. h.c. mult. Dr.-Ing. E.h. Peter Wriggers
Adresse
An der Universität 1
30823 Garbsen
Gebäude
Raum
317
Prof. em. Dr.-Ing. habil. Dr. h.c. mult. Dr.-Ing. E.h. Peter Wriggers
Adresse
An der Universität 1
30823 Garbsen
Gebäude
Raum
317
Funktion
Emeritierte und in den Ruhestand versetzte Professorinnen und Professoren
Leibniz Emeritus
Institut für Kontinuumsmechanik
  • Akademische Ausbildung
    1988 Habilitation in Mechanik, Universität Hannover
    1981 Promotion in Mechanik, Universität Hannover
    1976 Diplom in Bauingenieurwesen, Technische Universität Hannover
  • Beruflicher Werdegang
    seit 2008 Universitätsprofessor für Mechanik in der Fakultät für Maschinenbau an der Leibniz Universität Hannover
    2005 - 2006 Conjoint Professor an der University of Newcastle, Australien
    1998 - 2008 Universitätsprofessor für Mechanik in der Fakultät für Bauingenieurwesen und Geodäsie an der Leibniz Universität Hannover
    1990 - 1998 Universitätsprofessor für Mechanik im Fachbereich für Mechanik an der Technischen Universität Darmstadt
    1988 - 1988 Gastprofessor am Department of Civil Engineering der University of California, Berkeley, USA
    1984 - 1990Wissenschaftlicher Mitarbeiter am Institut für Baumechanik und Numerische Mechanik der Universität Hannover
    1983 - 1984 Visiting Scholar an der University of California, Berkeley, USA
    1976 - 1983Wissenschaftlicher Mitarbeiter am Institut für Baumechanik der Universität Hannover
  • Aktivitäten
    seit 2019Mitglied im wissenschaftlichen Beirat von Rocini (Rostock Centre for Interdisciplinary Implant Research) Link
    seit 2020Präsident des wissenschaftlichen Beirats des CIMNE (International Centre for Numerical Methods in Engineering) Link
    seit 2018Korrespondierendes Mitglied der Croatian Academy of Sciences and Arts
    2009 - 2022Mitglied des Executivkomites der IACM
    2015 - 2016Vorsitz des Executivkomites der AMD (Applied Mechanics Division) of ASME
    2015 - 2021 Vizepräsident für Forschung der Leibniz Universität Hannover
    seit 2015 Mitglied des "Board of Directors" und "Scientific Council" von CISM (International Center of Mechanical Sciences) Link
    seit 2014 Editor in Chief von „Computational Particle Mechanics“
    seit 2012Mitglied des wissenschaftlichen Beirats von CIMNE, UPC Barcelona
    2011 - 2018 Vizepräsident der IACM (International Association for Computational Mechanics)
    2011 - 2013 Vizepräsident der GAMM (Society for Applied Mathematics and Mechanics)
    2011 - 2016 Executivkomitee der Applied Mechanics Division der ASME
    2011 - 2017 Mitglied des DFG Senatsausschusses für Sonderforschungsbereiche
    2010 - 2019 Sprecher des internationalen Graduiertenkollegs IRTG1627: Virtual Materials and Structures and their Validation
    2009 - 2022Mitglied des Lenkungsausschusses des Höchstleistungsrechenzentrums der Universität Stuttgart (HLRS)
    2008 - 2012 Präsident der GACM (German Association for Computational Mechanics)
    2008 - 2010 Präsident der GAMM (Society for Applied Mathematics and Mechanics)
    2007 - 2011 Mitglied des ERC review panels für Starting and Consolidator Grants
    2006 - 2015 Mitglied des Auswahlausschusses der Alexander von Humboldt Stiftung für Forschungsstipendien
    2004 - 2011 Mitglied des DFG Fachkollegiums Architektur / Bauingenieurwesen sowie Medizintechnik
    seit 2004Mitglied der Acatech (German Academy of Technology Science)
    seit 2003 Mitherausgeber des “Bauingenieur”
    seit 2003Mitglied der Akademie für Wissenschaften und Literatur Mainz
    2001 - 2004Mitglied der Beratungskommission des "Transatlantic Science and Humanities Program" der Alexander von Humboldt Stiftung
    2001 - 2008Vizepräsident der GACM
    seit 2001 Editor in Chief von “Computational Mechanics”
    1996 - 2001 Mitglied des DFG Senatsausschusses Graduiertenkollegs
  • Ehrungen
    2015 Ehrendoktorwürde „Dr.-Ing. E.h.“ der TU Darmstadt
    2013 Ehrendoktorwürde „Dr. h.c.“ der ENS Cachan, Frankreich
    2013 Ehrendoktorwürde „Dr. h.c.“ der University of Technology Posen 
    2013 “Zienkiewicz Medal” der Polish Association for Computational Mechanics (PACM)
    2011 „Grand Prize“ of the Japan Society for Computational Engineering and Science (JSCES), Tokyo
    2011“Russell Severance Springer Professor“, Visiting Chair at ME Department, UC Berkeley
    2010 „IACM Award“ der IACM
    2008 „Euler Medal“ der ECCOMAS

    2006

    Computational Mechanics Award (IACM)

    2004

    "Highly Commended Award" for paper in Engineering Computations

    2003 - 2004

    ARC Linkage Professorship at University of Newcastle, NSW, Australia

    2002

    Fellow of the International Association for Computational Mechanics (IACM)

    2002

    "Literati Award for Excellence" to the best paper 2002 in Engineering Computations

    1981

    "Christian-Kuhlemann-Scholarship" for best PhD-thesis, University of Hannover
  • Mitgliedschaften
    seit 2018Korrespondierendes Mitglied der Croatian Academy of Sciences and Arts
    seit 2004 Mitglied von Acatech (Nationalakademie für Technikwissenschaften)
    seit 2004 Mitglied der Akademie für Wissenschaft und Literatur Mainz
    seit 1999 Mitglied der Braunschweigischen Wissenschaftlichen Gesellschaft
  • Bücher
    • Technische Mechanik, Band 4
      Hydromechanik, Elemente der Höheren Mechanik, Numerische Methoden
      Springer-Verlag Berlin/Heidelberg
      3. Aufl. 1999. XI, 434 S. 213 Abb. Brosch.
      ISBN 3-540-65205-1
  • Journals
    • Associated Editor
      International Journal for Numerical methods in Engineering (1998-2001)
      Der Bauingenieur (since 2003)
    • Member of the Editorial Board:
      • Since 1990    Engineering Computations
      • Since 1990    International Journal for Numerical Methods in Engineering
      • Since 1994    International Journal for Engineering Analysis and Design
      • Since 1995    Archives of Computational Methods in Engineering
      • Since 1997    Computers & Structures
      • Since 1997    International Journal of Solids and Structures
      • Since 1997    International Journal of Forming Processes
      • Since 1998    Engineering with Computers
      • Since 2000    Computer Methods in Applied Mechanics and Engineering
      • Since 2000    International Journal for Computational Civil and Structural Engineering
      • Since 2000    Computational Engineering Science
      • Since 2002    Journal of Computational Biomechanics
      • Since 2003    International Journal of Computational Methods
      • Since 2003    Latin American Journal of Solids and Structures
      • Since 2003    International Journal for Multiscale Computational Engineering
  • Forschungsprojekte

    FOR5250

    • In-silico-Design von Implantaten auf der Basis eines Multiskalenansatzes
      In der Forschungsgruppe sollen optimierte permanente Implantate entwickelt werden. Durch die additive Fertigung ergibt sich eine große Freiheit in der geometrischen Gestaltung. Dadurch kann die Gitterstruktur im Implantat gezielt eingestellt werden, um das Implantat optimal an den umgebenden Knochen anzupassen. Die Förderperiode 1 konzentriert sich auf permanente Implantate. Dabei muss besonders die Funktionsfähigkeit des Implantats über einen langen Belastungszeitraum garantiert sein. In diesem TP-7 wird ein skalenübergreifendes Modell entwickelt, das den Einfluss von Schädigungseffekten auf der Mikroskala, von Kerbeffekten der Gitterstrukturen auf der Mesoskala sowie das Stress Shielding auf der Makroskala berücksichtigt. Dazu wird ein neuartiger Homogenisierungsansatz eingeführt, der mittels Machine Learning eine zeiteffiziente Kopplung der Skalen erlaubt. Zusätzlich wird die Thermodynamische Topologieoptimierung weiterentwickelt, um skalenübergreifend das optimale digitale Implantat unter Berücksichtigung von prozessbedingten Schädigungs- und belastungsinduzierten Ermüdungseffekten zu bestimmen. Um das Optimum zwischen Gitterstruktur und Funktionsfähigkeit zu finden, wird ein effizienter Multiskalen-Algorithmus entwickelt. Das Ermüdungsverhalten bei Beanspruchung bei hohen (HCF, engl. High Cycle Fatigue) und sehr hohen Lastspielzahlen (VHCF, engl. Very High Cycle Fatigue) wird auf der Mikroskala modelliert. Dabei wird angenommen, dass das Versagen hauptsächlich an den Korngrenzen auftritt. Die Untersuchung des Einflusses der Gitterstruktur auf die Spannungs-Dehnungs-Beziehung findet auf der Mesoskala statt. Die Optimierung des Implantats hinsichtlich Betriebsfestigkeit, Tragfähigkeit und Morphologie wird schlussendlich auf der Makroskala durchgeführt. Der Datentransfer zwischen den einzelnen Skalen soll auf speziell entwickelten künstlichen neuronalen Netzen basieren.
      Leitung: Philipp Junker, Peter Wriggers
      Team: Hüray Ilayda Kök
      Jahr: 2022

    Damage modeling

    • In-silico-Design von Implantaten auf der Basis eines Multiskalenansatzes
      In der Forschungsgruppe sollen optimierte permanente Implantate entwickelt werden. Durch die additive Fertigung ergibt sich eine große Freiheit in der geometrischen Gestaltung. Dadurch kann die Gitterstruktur im Implantat gezielt eingestellt werden, um das Implantat optimal an den umgebenden Knochen anzupassen. Die Förderperiode 1 konzentriert sich auf permanente Implantate. Dabei muss besonders die Funktionsfähigkeit des Implantats über einen langen Belastungszeitraum garantiert sein. In diesem TP-7 wird ein skalenübergreifendes Modell entwickelt, das den Einfluss von Schädigungseffekten auf der Mikroskala, von Kerbeffekten der Gitterstrukturen auf der Mesoskala sowie das Stress Shielding auf der Makroskala berücksichtigt. Dazu wird ein neuartiger Homogenisierungsansatz eingeführt, der mittels Machine Learning eine zeiteffiziente Kopplung der Skalen erlaubt. Zusätzlich wird die Thermodynamische Topologieoptimierung weiterentwickelt, um skalenübergreifend das optimale digitale Implantat unter Berücksichtigung von prozessbedingten Schädigungs- und belastungsinduzierten Ermüdungseffekten zu bestimmen. Um das Optimum zwischen Gitterstruktur und Funktionsfähigkeit zu finden, wird ein effizienter Multiskalen-Algorithmus entwickelt. Das Ermüdungsverhalten bei Beanspruchung bei hohen (HCF, engl. High Cycle Fatigue) und sehr hohen Lastspielzahlen (VHCF, engl. Very High Cycle Fatigue) wird auf der Mikroskala modelliert. Dabei wird angenommen, dass das Versagen hauptsächlich an den Korngrenzen auftritt. Die Untersuchung des Einflusses der Gitterstruktur auf die Spannungs-Dehnungs-Beziehung findet auf der Mesoskala statt. Die Optimierung des Implantats hinsichtlich Betriebsfestigkeit, Tragfähigkeit und Morphologie wird schlussendlich auf der Makroskala durchgeführt. Der Datentransfer zwischen den einzelnen Skalen soll auf speziell entwickelten künstlichen neuronalen Netzen basieren.
      Leitung: Philipp Junker, Peter Wriggers
      Team: Hüray Ilayda Kök
      Jahr: 2022

    Improving Accuracy and Performance of Meshfree Methods

    • Process Simulation for Selective Laser Melting
      A phase change model for solution with the meshfree Galerkin OTM method is developed.
      Leitung: Christian Weißenfels, Peter Wriggers
      Team: M.Sc. Henning Wessels
      Jahr: 2016
    • ISPH-based Simulation of the Selective Laser Melting Process
      Development of a thermo-mechanical model for the simulation of the SLM process.
      Leitung: Christian Weißenfels, Peter Wriggers
      Team: M.Sc. Jan-Philipp Fürstenau
      Jahr: 2017
    • Using Machine Learning to Improve the Modelling of Machining and Cutting Processes
      Metal cutting is a fundamental process in industrial production. The fast and accurate on-line prediction of metal cutting processes is crucial for the Intelligent Manufacturing (IM). With the advent of high-speed computing, robust numerical algorithms and machine learning technology, computational modelling serves as a tool for not only accurate but also fast predicting the complex machining processes and understanding the complex physics. In this work, the machine learning based numerical model is developed for simulation of metal cutting processes.
      Leitung: C. Weißenfels, P. Wriggers
      Team: M.Sc. Dengpeng Huang
      Jahr: 2018
      Förderung: China Scholarship Council (CSC)
    • Peridynamic Galerkin Methods
      Simulation-driven product development is nowadays an essential part in the industrial digitalization. Notably, there is an increasing interest in realistic high-fidelity simulation methods in the fast-growing field of additive and ablative manufacturing processes. Thanks to their flexibility, meshfree solution methods are particularly suitable for simulating the stated processes, often accompanied by large deformations, variable discontinuities, or phase changes. Furthermore, in the industrial domain, the meshing of complex geometries represents a significant workload, which is usually minor for meshfree methods. Over the years, several meshfree schemes have been developed. Nevertheless, along with their flexibility in discretization, meshfree methods often endure a decrease in accuracy, efficiency and stability or suffer from a significantly increased computation time. Peridynamics is an alternative theory to local continuum mechanics for describing partial differential equations in a non-local integro-differential form. The combination of the so-called peridynamic correspondence formulation with a particle discretization yields a flexible meshfree simulation method, though does not lead to reliable results without further treatment. In order to develop a reliable, robust and still flexible meshfree simulation method, the classical correspondence formulation is generalized into the Peridynamic Galerkin (PG) methods in this project. On this basis, conditions on the meshfree shape functions of virtual and actual displacement are presented, which allow an accurate imposition of force and displacement boundary conditions and lead to stability and optimal convergence rates. Based on Taylor expansions moving with the evaluation point, special shape functions are introduced that satisfy all the previously mentioned requirements employing correction schemes. In addition to displacement-based formulations, a variety of stabilized, mixed and enriched variants are developed, which are tailored in their application to the nearly incompressible and elasto-plastic finite deformation of solids, highlighting the broad design scope within the PG methods. Compared to related Finite Element formulations, the PG methods exhibit similar convergence properties. Furthermore, an increased computation time due to non-locality is counterbalanced by a considerably improved robustness against poorly meshed discretizations.
      Leitung: Christian Weißenfels, Peter Wriggers
      Team: M.Sc. Tobias Bode
      Jahr: 2019
    • Numerical simulation of pile installation in a hypoplastic framework using an SPH based Method
      In this project, a 3D computational tool using smoothed particle hydrodynamics (SPH) is developed which based on a hypoplastic constitutive approach for the mechanical behavior of the soil. The numerical code is firstly validated against a benchmark problem. Then several test cases are simulated including monotonic and vibratory penetration of piles into the soil. A good agreement with the experimental observation is found. Additionally, the impact of pile running in the presence of sheetpiles (retainers) are investigated to see how pile running can alter the applied forces on the sheet piles. The simulation of such complex geotechnical problems which involve large deformation, material nonlinearity and moving boundary conditions demonstrates the applicability and versatility of the proposed numerical tool in this field.
      Leitung: Peter Wriggers
      Team: Meisam Soleimani, Christian Weißenfels
      Jahr: 2020

    In Silicio Analyses

    Virtual Elements For Engineering Appications

    • 2D VEM for crack-propagation
      Leitung: F. Aldakheel, B. Hudobivnik, P. Wriggers
      Team: A. Hussein
      Jahr: 2018
      Förderung: IRTG 1627
    • Virtual element method (VEM) for phase-field modeling of brittle and ductile fracture
      Leitung: F. Aldakheel, B. Hudobivnik, P. Wriggers
      Jahr: 2018
      Förderung: DFG SPP 1748
    • Virtual Element Method for Dynamic Applications
      The Virtual Element Method is a recent developed discretization method, which can be seen as an extension of the classical Galerkin finite element method. It has been applied to various engineering fields, such as elasto-plasticity, multiphysics, damage and fracture mechanics. This project focuses on the extension of VEM towards dynamic applications. In the first part the appropriate computation of the Massmatrix regarding the vitual element ansatzspace will be done. In future works, VEM will be applied to engineering problems, considering the dynamic behavior.
      Leitung: F. Aldakheel, B. Hudobivnik, P. Wriggers
      Team: M. Cihan
      Jahr: 2019
    • Virtual Element Method for 3D Contact
      The computational modeling of contact has always been a challenging task, especially when the interface between two or more bodies, which will come into contact, has a non-conforming mesh. In this case, the virtual element method (VEM) can be used to modify the interface mesh, such that a conforming mesh arises. In this project, we employ the virtual element method in 3D to project the interface meshes between each other, such that new nodes can be inserted on both bodies, to obtain matching meshes at the interface. The insertion of new nodes does not change the Ansatz or total number of elements. These new nodes are either stemming from already existing vertices, or edge-to-edge intersections (a). The later can be easily inserted in to the existing mesh, since this nodes are located at element edges. Nodes, which are getting projected from vertices will most probably lie in element faces. The insertion of these nodes needs an additional treatment. However, the projection-based node insertion algorithm leads to matching meshes and allows to employ a simple node-to-node contact at the interface. The numerical results are showing that this way of modeling contact passes the patch test exactly (b)-(c).
      Leitung: F. Aldakheel, B. Hudobivnik, P. Wriggers
      Team: M. Cihan
      Jahr: 2020
    • Virtual element formulation for trusses and beams
      The virtual element method (VEM) was developed not too long ago, starting with the paper Beirao da Veiga et al. (2013) related to elasticity in solid mechanics. The virtual element method allows to revisit the construction of different elements in solid mechanics, however, has so far not been applied to one dimensional structures like trusses and beams. In this project, several VEM elements suitable for trusses and beams are derived. It could be shown that the virtual element methodology produces elements that are equivalent to well know finite elements but also elements that are different, especially for higher order ansatz functions, like 2nd and 3rd order for the truss and 4th order for the beam. It will be shown that these elements can be easily incorporated in classical finite element codes since they have the same nodal degrees of freedom as finite beam elements. Furthermore, the formulation allows to compute nonlinear structural problems undergoing large deflections and rotations.
      Leitung: P. Wriggers
      Jahr: 2021
    • Virtual Kirchhoff-Love plate elements for isotropic and anisotropic materials
      The virtual element method allows to revisit the construction of Kirchhoff-Love elements because the C1-continuity condition is much easier to handle in the VEM framework than in the traditional finite element methodology. Here we study the two most simple VEM elements suitable for Kirchhoff-Love plates as stated in (Brezzi and Marini (2013)). The formulation contains new ideas and different approaches for the stabilization needed in a virtual element, including classic and stabilization. An efficient stabilization is crucial in the case of C1-continuous elements because the rank deficiency of the stiffness matrix associated to the projected part of the ansatz function is larger than for C0-continuous elements. This project aims at providing engineering inside in how to construct simple and efficient virtual plate elements for isotropic and anisotropic materials and at comparing different possibilities for the stabilization. Different examples and convergence studies discuss and demonstrate the accuracy of the resulting VEM elements. Finally, reduction of virtual plate elements to triangular and quadrilateral elements with 3 and 4 nodes, respectively, yields finite element like plate elements. These C1-continuous elements can be easily incorporated in legacy codes and demonstrate an efficiency and accuracy that is much higher than provided by traditional finite elements for thin plates.
      Leitung: P. Wriggers, B. Hudobivnik
      Team: P. Wriggers, B. Hudobivnik, O. Allix
      Jahr: 2021

    Phase Field Modeling of Fracture in Multi-Field Environments

    Multiscale and Multifield problems

    • Multiscale Method for Hydro-Chemo-Thermo-Mechanics Coupling due to Alkali Silica Reaction in Concrete
      Alkali Silica Reaction(ASR) is one of most determinant reasons leading to the deterioration of concrete structures, which can be ascribed to the expansion of gel produced by ASR in the microstructural level of concrete. The challenge in the modeling of ASR is due to the necessity to take into account the presence of heterogeneities and physical processes distributed over multiple length scales. With increasing computation power and the tomography scan technology, it can be implemented by numerical simulation . In this contribution, 3D multiscale hydro-chemo-thermal-mechanical coupling based on a staggered method is demonstrated, which explicitly describes the damage evolution originating from the chemical reaction in the microscale and the dependence on environmental factors.
      Leitung: P. Wriggers
      Team: T. Wu
      Jahr: 2009
    • MULTIPHYSICS COMPUTATIONAL HOMOGENIZATION METHODOLOGIES
      Computational homogenization techniques that are amenable to a multiscale implementation are being developed for multiphysics problems at the finite deformation regime. Applications include the estimation of the contact conductance for rough interfaces and the modeling of the coupled thermomechanical response of heterogeneous materials.
      Leitung: P. Wriggers, I. Temizer
      Jahr: 2009
    • Direct Numerical Simulation of Multiphase Flows
      Multiphase flows consisting of a continuous fluid phase and a dispersed phase of macroscopic particles are present in many engineering applications. In general, a main task in the study of the particle-laden fluid flow of an application is to make predictions about the system's nature for various boundary conditions, since, depending on the volume fraction and mass concentration of the dispersed phase a fluid-particle system shows quite different flow properties. Unfortunately, often it is impossible to investigate such a system experimentally in detail or even at all. An option to capture and to predict its properties is performing a direct numerical simulation of the particulate fluid. For this purpose, an efficient approach is developed in this project by coupling the discrete element method and finite element method.
      Leitung: P. Wriggers
      Team: B. Avci
      Jahr: 2009
    • Numerical modeling of electrical contacts
      The focus of this work is the investigation of the behavior in electrical contacts, where electrical, thermal and mechanical fields are coupled. Specifically, theoretical constitutive models for the electrical conductance and electrical wear phenomena are developed and implemented in a three dimensional finite element setting. Also a new relation for wear is proposed, where the amount of wear is coupled to the dissipation arising at the contact interface. </a></p>
      Leitung: P. Wriggers
      Team: C. Weißenfels
      Jahr: 2009
    • RAMWASS - Integrated Decision Support System for Risk Assessment and Management
      The objective of the EU-project RAMWASS is to develop and validate a new decision support system (DSS) for the risk assessment and management for the prevention and/or reduction of the negative impacts caused by human activities on the water/sediment/soil system at river basin scale in fluvial ecosystems.
      Leitung: P. Wriggers
      Team: B. Avci
      Jahr: 2009
    • Homogenization procedures for coupled thermo-chemo-mechanical problems
      In order to understand processes of continuum damage mechanics it is necessary to investigate thermo-chemo-mechanical coupled processes at micro scale. However for engineering purposes it is still necessary to be able to model these processes at macro scale, especially when large structures have to be designed. Thus a homogenization procedure or a FE^2 framework is necessary to transform the relation, describing the coupled thermo-chemo-mechanical response at micro scale to the macro scale. The related equations and procedures have to be developed and implemented in a finite element software system.
      Leitung: P. Wriggers, E. Baranger
      Team: Jin Man Mok
      Jahr: 2013
    • Multi-Fluid Simulations for High Density Ratios
      Although the contact between fluids or gases of different densities is a common event in nature, like the interaction of water and air, the simulation of multiple fluids often comes along with numerous problems. With the Lagrangian description of continuous fluids in terms of the Smoothed Particle Hydrodynamics (SPH) method multi-fluid interactions within the particle scale can simulated. Nevertheless with the standard SPH algorithms multi-fluid problems can not be solved because of the density jumps at the interfaces. Within the project the state of the art of current multi-fluid approaches are compared and evaluated to develop appropriate methods for the simulation of multi-fluid systems with high density ratios.
      Leitung: P. Wriggers, B. Avci
      Team: J.-P. Fürstenau
      Jahr: 2014
    • Towards multiscale modeling of Abrasive wear
      The work is motivated towards understanding wear as a multiscale-multiphysics approach. A 3D framework is developed to simulate cracks propagation in a microstructure due to contact loading to eventually predict wear trends in filled elastomeric compounds.
      Leitung: P. Wriggers
      Team: A. B. Harish
      Jahr: 2015
    • Entropic approach to modeling Mullins effect in non-crystallizing filled elastomers
      The work was done in collaboration with Mrs. Aarohi B. Shah and Dr. Julian J Rimoli of School of Aerospace Engineering, Georgia Tech, USA. In this work, we investigate non-crystallizing nanoparticle-reinforced polymers. The effects of the interface rubber between elastomeric matrix and filler particles and its alteration are investigated as a primary cause of Mullins and Payne effect.
      Leitung: P. Wriggers, J. J. Rimoli
      Team: A. B. Harish, A. B. Shah
      Jahr: 2016

    Life time prediction and failure of modern complex materials and structures

    Material modeling

    • DEVELOPMENT OF A MATERIAL MODEL FOR METAL SHEETS AT FINITE DEFORMATION
      Technical procedures claim an improved material model for the simulation of metal forming processes. An effective, anisotropic elastoplastic material model for the macroscopic material behaviour for sheet metals is developed for further usage in commercial finite element programs.
      Leitung: P. Wriggers, S. Löhnert
      Team: E. Lehmann, S. Zeller
      Jahr: 2009
    • Multiskalenmodellierung und erweiterte finite Elmente Analyse von Bruchprozessen in Keramik
      Die erweiterte finite Elemente Methode (XFEM) ermöglicht die Modellierung von Rissen unabhängig von der Vernetzung. Dadurch hat sich die XFEM für Rissberechnungen durchgesetzt. Vor allem in der Nähe von Makrorissspitzen muss die Mikrostruktur des Materials berücksichtigt werden, da Mikrorisse das Risswachstum verstärken oder abschwächen können. Mikrorisse entstehen unter Belastung in der Nähe des fortschreitenden Makrorisses. Dies motiviert eine Mehrskalenmodellierung z.B. mit der Multiskalenprojektionsmethode, die in der Lage ist, Feinskaleneffekte dort genau aufzulösen, wo es notwendig ist. Auch wenn die Modellierung von Rissen mit der XFEM unabhängig von der Vernetzung ist, hat das Netz einen Einfluss auf die Genauigkeit der Spannungen. Spannungssingularitäten können mit feineren Netzen besser erfasst werden. Die Berechnung eines Diskretisierungsfehlers für den Mikrobereich ermöglicht eine adaptive Verfeinerung des Netzes, so dass genaue Ergebnisse erzielt werden können. Die verwendeten Modelle werden durch einen Vergleich mit experimentellen Daten validiert.
      Leitung: P. Wriggers, S. Löhnert
      Team: C. Prange
      Jahr: 2009
    • FAILURE ANALYSIS - ERROR ESTIMATION FOR MULTISCALE METHODS
      This project is concerned with the development of tools for error-estimation based adaptive multiscale failure analysis. In order to enable a more accurate mechanical analysis of composite aircraft substructures, existing discretisation error estimators will be improved to be used as indicators for mesh refinement. Additionally, physical error estimators will be developed to identify regions where higher-order material modelling is required.
      Leitung: P. Wriggers
      Team: N. Hajibeik
      Jahr: 2009
    • ADAPTIVE MULTISCALE MODELING AND ANALYSIS OF HETEROGENEOUS MATERIALS
      Accurate computational analyses of a composite structure requires multiple levels of resolution: (i) a region where effective elastic properties are employed, (ii) a region where embedded micro-macro problems are solved, and (iii) a region where explicit microstructural evaluation is required. Development of such computational schemes for the adaptive multiscale analysis of heterogeneous materials is the main purpose of this project.
      Leitung: P. Wriggers, I. Temizer
      Jahr: 2009
    • Crack propagation and crack coalescence in a multiscale framework
      In this project a numerical framework for propagating and intersecting cracks on micro and macro scales is set up. Modeling cracks using the eXtended Finite Element Method (XFEM) provides an accurate and efficient numerical framework to model propagating and intersecting cracks. Since cracks of different length scales are assumed, a multiscale method is applied in order to be numerical efficient.
      Leitung: S. Löhnert, P. Wriggers
      Team: M. Holl
      Jahr: 2010
    • Multiscale Methods for Fracturing Solids
      In this project multiscale methods and homogenization techniques for the numerical simulation of three dimensional fracture processes are developed. These methods are important in aerospace and automotive industries and many other fields of mechanical and civil engineering as well as in bio-mechanics and material science. They will improve the prediction of the failure of structures.
      Leitung: P. Wriggers, S. Löhnert
      Team: D. Müller-Hoeppe
      Jahr: 2011
    • Mehrskalenmodellierung von lokalisiertem duktilen Versagen
      Es existieren viele phänomenologische Materialmodelle, die duktile Schädigung vorhersagen. Um jedoch die Materialeigenschaften und Schädigungsmechanismen der vorliegenden Mikrostrukturen flexibel einzubinden, ist eine Mehrskalenformulierung notwendig. Die existierenden Multiskalenmodelle beschränken sich jedoch zumeist auf spröde Mikroschädigung. Aus diesem Grund soll in diesem Projekt eine Mehrskalenmethode entwickelt werden, die lokalisiertes plastisches Versagen aufgrund einer duktil schädigenden Mikrostruktur vorhersagen kann.
      Leitung: P. Wriggers
      Team: H. Clasen
      Jahr: 2012
      Förderung: DFG im Normalverfahren
    • Computational homogenisation of elasto plastic material
      Particle-matrix materials are commonly used in different fields(aerospace components, bicycle frames and racing car bodies) for its mechanical and economical advantages,such as high strength, low weight and less expense.However,Because of the microstructural complexities,it is very time and labor consuming to determin the mechanical properties of composite materials. Hence,in order to reduce laboratory expense, numerical simulations via Homogenized techniques are performed on RVE to predict mechanical behavior of composite material.
      Leitung: P.Wriggers
      Team: Chao Zhang
      Jahr: 2012
    • Mesoscale modeling of large deformation behavior of nanoparticle-reinforced elastomers
      Elastomeric materials exhibit distinct fracture behavior compared to several other materials. The fracture process involves extensive chain scission (similar to crazing) in rubbery elastomers. Upon loading, the chains start to align along the direction of loading forming a zone just ahead of the crack tip. Upon further loading, more chains are drawn in from the bulk to eventually fail and leading to formation of crack front. Additionally, due to the viscoelastic nature of these polymers, there is a viscoelastic dissipation of energy just ahead of the crack tip leading to phenomena like crack tip blunting etc. A 3D finite thickness cohesive zone mode, alongside directional node release is used for modeling fracture in filled elastomeric materials.
      Leitung: P.. Wriggers
      Team: A. B. Harish
      Jahr: 2015
    • Process Simulation for Selective Laser Melting
      A phase change model for solution with the meshfree Galerkin OTM method is developed.
      Leitung: Christian Weißenfels, Peter Wriggers
      Team: M.Sc. Henning Wessels
      Jahr: 2016
    • Nanoindentation for material property characterization
      In this work, techniques are developed for nanoindentation of soft polymers and brittle powdery materials and measurement of properties like modulus, hardness and fracture toughness.
      Leitung: P. Wriggers, S. Löhnert
      Team: A. B. Harish, V. Kruppernikova
      Jahr: 2016
    • Hypoplastic material models for soil-structure interaction problems
      In this work, a hypoplastic material model is implemented using AceGen with an eventual goal to model soil-structure interaction.
      Leitung: P. Wriggers, C. Weissenfels
      Team: A. B. Harish
      Jahr: 2016
    • Entropic approach to modeling Mullins effect in non-crystallizing filled elastomers
      The work was done in collaboration with Mrs. Aarohi B. Shah and Dr. Julian J Rimoli of School of Aerospace Engineering, Georgia Tech, USA. In this work, we investigate non-crystallizing nanoparticle-reinforced polymers. The effects of the interface rubber between elastomeric matrix and filler particles and its alteration are investigated as a primary cause of Mullins and Payne effect.
      Leitung: P. Wriggers, J. J. Rimoli
      Team: A. B. Harish, A. B. Shah
      Jahr: 2016
    • In silico morphogenesis of collagen tissues for targeted drugs and bio-printing
      This project targets to understand the mechanisms behind the morphogenesis and the development of living tissues. To this aim, mechanical and biological actions that contribute to confer tissue desired topology and functionality will be modelled and analysed in silico. A computational framework for the modeling of tissue morphogenesis in natural and bio-printed systems will be developed. In particular, the project will address: the multiscale hierarchical and organized arrangement of tissue constituents; the chemo-mechanical interaction among tissue constituents and among cells; the chemo-mechano-biological mechanisms driving growth and remodeling; the extrusion and the curing of multicellular aggregates blended with bio-inks. Obtained results will target to elucidate mechanisms behind tissue functional/dysfunctional structure; conceive targeted drug systems for stimulating optimal molecular pathways promoting tissue healing; develop novel or optimize existing 3D bio-printing technologies.
      Leitung: M. Marino
      Jahr: 2017
      Förderung: Masterplan SmartBiotecs, MWK (Lower Saxony, Germany)

    Biomedical technology

    • Numerical simulation and experimental validation of biofilm formation
      In this Reserch , a state-of-the-art 3D computational model has been developed to investigate biofilms in a multi-physics framework using smoothed particle hydrodynamics (SPH) based on a continuum approach. Biofilms are in fact aggregation of microorganisms such as bacteria. Biofilm formation is a complex process in the sense that several physical phenomena are coupled and consequently different time-scales are involved. On one hand, biofilm growth is driven by biological reaction and nutrient diffusion and on the other hand, it is influenced by the fluid flow causing biofilm deformation and interface erosion in the context of fluid and deformable solid interaction (FSI). The geometrical and numerical complexity arising from these phenomena poses serious complications and challenges in grid-based techniques such as finite element (FE). Such issues are generally referred to as mesh distortion. Here the solution is based on SPH as one of the powerful meshless methods. SPH based computational modeling is quite new in the biological community and the method is uniquely robust in capturing the interface-related processes of biofilm formation especially erosion. The fact is that SPH is a versatile tool owing to its adaptive Lagrangian nature in the problems whose geometry is temporarily varying (dynamic). Moreover, its mesh-less feature is considered to be favorable in interpreting the method as a particle based one. Hence, it is quite straight forward to incorporate complex interactions and ad-hoc rules at the particle level into the method. This is the case for the problems with coupled governing equations with different time and length scale. In this thesis all different physics which account for biofilm formation have been implemented in the framework of SPH and one can say that this tool is purely SPH based. Besides the numerical simulation, experiments were conducted by our partners in the medical school of Hannover. The obtained numerical results show a good agreement with experimental and published data which demonstrates that the model is capable of predicting overall spatial and temporal evolution of the biofilms. The developed tool can be employed in either controlling the detrimental biofilms or harnessing the beneficial ones.
      Leitung: Peter Wriggers
      Team: Meisam Soleimani, Peter Wriggers, Meike Stiesch
      Jahr: 2013
    • Gekoppelte Simulation von Aerosolströmungen in asthmatischen Bronchien
      Das Ziel dieses Projektvorhabens ist es, auf Basis eines gekoppelten 3D Mehrfeldmodells die partikelbeladene Luftströmung in gesunden sowie in asthmatisch verengten Bronchien anhand von numerischen Simulationen zu studieren.
      Leitung: P. Wriggers, B. Avci
      Team: J. Stasch, J.-P. Fürstenau
      Jahr: 2014
      Förderung: Leibniz Universität Hannover, Wege in die Forschung
    • Advanced multiscale computational mechanics for physiopathological behavior analysis of tissues and organs
      The physiological functionalities of large biological structures are highly affected by the mechanics of living tissues which is, in turn, related to microstructural arrangement of histological constituents and biochemical environment at nanoscale. Present research activity aims to develop a novel tissue multiscale description, including also inelastic mechanisms, coupled with an advanced computational formulation under finite strain and large-displacement assumptions. As a result, an innovative in-silico tool for simulation of organs and large biological structures will be developed, allowing to predict pathology-related damage or pharmacological-related healing and providing novel diagnostic and clinical indications for highly patient-specific medical treatments.
      Leitung: P. Wriggers, M. Marino
      Jahr: 2015
      Förderung: Alexander von Humboldt-Stiftung
    • Patient-Specific FSI Analysis of the Blood Flow in the Thoracic Aorta
      The complexity of numerical modeling and simulation of blood flow in patient-specific thoracic aorta geometries leads to a number of major computational challenging issues. For instance, for an adequate simulation of the flow and pressure field, the incompressible Navier-Stokes equations have to be solved with the assumption that the relatively thin blood vessels suffer large displacements and undergo large elastic or visco-elastic deformations caused by the pulsatile blood flow. Subsequently, inaccurate predictions would be obtained for the hemodynamic quantities with the very simplifying rigid-wall assumption (CFD modeling). Moreover, when applying only the CFD modeling approach the essential phenomena of pressure wave propagation in cardiovascular systems are disregarded, however these phenomena are of major relevance for clinical practice. Accordingly, strongly coupled FSI schemes are inevitable for comprehensive blood flow simulations in arterial systems, and as blood and vascular walls have comparable densities, monolithic or at least partitioned strongly coupled FSI schemes are required for solving the multi-physics problem with its inherent significant added-mass effects.
      Leitung: P. Wriggers, B. Avci
      Team: B. Avci
      Jahr: 2016
    • Computational modeling of in-stent restenosis
      This project aims to develop a computational tool for the modeling of the long-term behaviour of stent deployment, with a special focus on both current and prospective approaches. A multiscale description of arterial constitutive behaviour will be employed, including possible damage due to the stenting procedure. Moreover, the chemo-biological mechanisms underlying the growth and remodelling due to wound healing in tissues will be introduced. Therefore, a multiphysics computational framework will be developed and applied for the analysis of both metal and drug-eluting stents. The project will allow to identify the dominant mechanisms driving in-stent restenosis, deciphering the role of the different molecular species in the pathological remodeling of arteries. The final target is to optimise the clinical outcome of current approaches and propose targeted therapeutic approaches.
      Leitung: M. Marino
      Jahr: 2017
      Förderung: Masterplan SmartBiotecs, MWK (Lower Saxony, Germany)
    • Red blood cell simulation using a coupled shell-fluid analysis purely based on the SPH method
      If the rheological behavior of a Red-Blood-Cell (RBC) changes, for example due to some infection, it is reflected in its deformability when it passes through the microvessels. It can severely affect its proper function which is providing the oxygen and nutrient to the living cells. In this research project, a novel 3D numerical method has been developed to simulate RBCs based on the interaction between a shell-like solid structure and a fluid. RBC is assumed to be a thin shell encapsulating an internal fluid (Cytoplasm) which is submerged in an external fluid (blood plasma). The approach is entirely based on the smoothed particle hydrodynamics (SPH) method for both fluid and the shell structure. The method was motivated by the goal to benefit from the Lagrangian and meshless features of SPH in order to handle several complexities in the problem due to the coupling between the RBC membrane as a deformable elastic shell and interior/exterior fluids.
      Leitung: Peter Wriggers
      Team: Meisam Soleimani
      Jahr: 2017
      Laufzeit: 3 Jahre

    High Performance Computing (HPC)

    • In many cases, massive parallel large-scale computations are indispensable for solving problems of practical interest. The numerical treatment of such class problems requires not only highly efficient scalable parallel solvers, moreover, efficient parallel algorithms covering the whole simulation pipeline – also including pre- and post-processing, mesh generation and design solvers considering uncertainties – are essential to model and to simulate large-scale or exascale class problems. The specific goal of this project is therefore the development and implementation of new parallel algorithms and methods that will allow to solve large-scale class problems with high efficiency.
      Leitung: P. Wriggers, B. Avci
      Team: B. Avci
      Jahr: 2014
      Förderung: FP7 of the EU
    • ISPH-based Simulation of the Selective Laser Melting Process
      Development of a thermo-mechanical model for the simulation of the SLM process.
      Leitung: Christian Weißenfels, Peter Wriggers
      Team: M.Sc. Jan-Philipp Fürstenau
      Jahr: 2017

    Fracture Mechanics/ XFEM

    • Crack propagation and crack coalescence in a multiscale framework
      In this project a numerical framework for propagating and intersecting cracks on micro and macro scales is set up. Modeling cracks using the eXtended Finite Element Method (XFEM) provides an accurate and efficient numerical framework to model propagating and intersecting cracks. Since cracks of different length scales are assumed, a multiscale method is applied in order to be numerical efficient.
      Leitung: S. Löhnert, P. Wriggers
      Team: M. Holl
      Jahr: 2010
    • Large Deformation Cohesive-Zone Element for Fracture in Rubbery Polymers
      In this work, a 3D cohesive zone element is developed considering material and geometric nonlinearities and suitable for modeling large deformations and rotations.
      Leitung: P. Wriggers
      Team: A. B. Harish
      Jahr: 2015
    • Nanoindentation for material property characterization
      In this work, techniques are developed for nanoindentation of soft polymers and brittle powdery materials and measurement of properties like modulus, hardness and fracture toughness.
      Leitung: P. Wriggers, S. Löhnert
      Team: A. B. Harish, V. Kruppernikova
      Jahr: 2016

    Multiscale and multiphysics material modelling of polycrystalline metals and forming processes

    • Creep deformation of nickel based superalloys
      Modeling of nickel based superalloys on two scales using crystal plasticity and XFEM methods.
      Leitung: P. Wriggers
      Team: L. Munk
      Jahr: 2018
    • Modelling and simulation of the joining zone during the tailored forming process
      In this project, micromechanically motivated thermo-chemo-mechanical material models are developed on a microscopic length scale and transformed to an effective macroscopic material model. In order to achieve a high mechanical strength of the hybrid solid component, these material models are used to evaluate the sensitivity of different process parameters after joining and during forming and heat treatment. Moreover, with aid of the the evaluation results the material behaviour of the joining zone can be accurately adjusted during the Tailored Forming process.
      Leitung: F. Aldakheel, P. Wriggers
      Team: C. Böhm, F. Töller
      Jahr: 2019
      Förderung: DFG im Rahmen des SFB 1153
    • Water-induced damage mechanisms of cyclic loaded high-performance concretes
      The use of offshore wind energy is expanding and fatigue-loaded concrete structures are built that are submerged in water. This currently already applies to so-called grouted joints, where high-strength fine-grained concrete (grout) is used in the steel support structures of offshore wind turbines. Such constructions are subjected to several hundred million load cycles within their service life. An increased water content in the concrete results from the offshore exposure which is principally different to onshore constructions,. Comparatively few investigations of fatigue-tested concrete specimens immersed in water are documented in the literature. Despite the fact, that considerably scatterings occur in these results a clear tendency can be observed. Specimens that are immersed in water have a significantly lower fatigue resistance compared with specimens tested in air. Some investigations also show that fatigue-loaded concrete specimens immersed in water have a significant change in their fracture behaviour compared with specimens tested in air. This can be seen, in tests, for example, by ascending air bubbles, wash-outs of fine particles and premature crack initiation.Water-induced damage mechanisms in fatigue-loaded concrete have indeed been recognised in the past, but they were not identified and described with sufficient precision. Consequently, they cannot be quantified reliably. Based on the existing knowledge gap, the vast majority of these mechanisms have currently escaped numerical modelling and simulation.The aim of this research project is to understand, analyse and quantify macroscopically water-induced damage mechanisms of fatigue-loaded high-performance concretes in the Experimental-Virtual-Lab (EVL) with complementary very latest state-of-the-art experimental methods. At the same time, models will be created and numerically implemented on a micromechanical basis that enables proving of hypotheses that will be derived from the experimental investigations. The structural data serve for the validation of these models; the data will be determined by µCT scans, NMR measurements and mercury intrusion porosimetry.After a first clarification of the origin of mechanisms by the EVL, modelling at the macroscopic level will be attempted on the basis of the micromechanical investigations. In this way it will be verified, how the water influences the degradation behaviour of fatigue-loaded high-performance concretes and which additional active, water-induced damage mechanisms are decisively involved in the degradation process. It will be possible for the first time to carry out a prediction of the degradation behaviour of fatigue-loaded high-performance concretes immersed in water based on microstructurally orientated parameters.
      Leitung: Fadi Aldakheel, Peter Wriggers
      Jahr: 2020
      Förderung: DFG SPP 2020, zweite Förderperiode
      Laufzeit: 3 Jahre

    Contact mechanics

    • MULTISCALE CONTACT HOMOGENIZATION OF GRANULAR INTERFACES
      Dry granular third bodies are frequently encountered at multiple scales of contact interfaces in contexts that range from mechanical problems of tire traction and semiconductor manufacturing to biological problems of wear debris generation and mobility in implant joints. The investigations that are envisaged within this proposal will provide further insight into the modeling and simulation of third body effects in a fully nonlinear three-dimensional virtual setting that accounts for inelastic phenomena.
      Leitung: P. Wriggers, I. Temizer
      Team: R. Weidlich
      Jahr: 2009
    • Mutiscale FEM approach for rubber friction on rough surfaces
      Understanding the frictional behaviour of elastomers on rough surfaces is of high practical importance in many industrial applications. For example the traction of a tire is directly linked to the material properties of the considered elastomer and the surface conditions of the road track. One goal of our studies is to gain a deeper understanding of the underlying contact physics at all length scales. Another aim is to determine a macroscopic coefficient of friction for varying material and surface properties and to validate the results with experimental data.
      Leitung: P. Wriggers
      Team: P. Wagner
      Jahr: 2012
    • Contact models for soil mechanics
      The installation of foundations influences strongly the load bearing capacity of the soil. The large discrepancy between experimental and numerical results, using Coulomb friction law for modeling the soil structure interaction, points out that new strategies to solve this kind of problems are necessary. Experimental observations show that for rough surfaces of the structure the friction angle at the contact zone corresponds to the friction angle of the soil. This leads to the conclusion that the contact zone lies completely within the soil. A way to improve the friction laws for soil structure interactions is to project the soil models onto the contact surface which is the motivation of this work. </a></p>
      Leitung: P. Wriggers
      Team: C. Weißenfels
      Jahr: 2012
    • Application of the Virtual Element Method to Non-Conforming Contact Interfaces
      When using standard Finite Elements the discretization is subject to limitations depending on the element geometry. In contrast to this the Virtual Element Method offers the possibility for elements with an arbitrary number of nodes and special geometries like non-convex polygons or hanging nodes. In this Project the application of the Virtual Elements to different problems is investigated. Here it is used to create an efficient contact discretization.
      Leitung: P. Wriggers
      Team: W.T. Rust
      Jahr: 2014
    • Towards multiscale modeling of Abrasive wear
      The work is motivated towards understanding wear as a multiscale-multiphysics approach. A 3D framework is developed to simulate cracks propagation in a microstructure due to contact loading to eventually predict wear trends in filled elastomeric compounds.
      Leitung: P. Wriggers
      Team: A. B. Harish
      Jahr: 2015

    Additive Manufacturing

    Discrete Elements and Molecular Dynamics

    • Discrete Element Method
      This project is concerned with the development of a discrete element method (DEM) code for the simulation of large particle systems in 3-D, where also complex moving boundary geometries can be taken into account. The DEM is a well established numerical method to simulate systems consisting of granular matter. Granular mixing, tumbling mills, transport of particles via conveyor belts or screw conveyors are just some examples of important particulate processes in industry sectors like mining, pharmaceutical and food industries. For such systems, the optimization of the design variables as well as the appropriate choice of the operating parameters is still a difficult and a challenging task.
      Leitung: P. Wriggers
      Team: B. Avci
      Jahr: 2011

    Artificial Intelligence

    • Using Machine Learning to Improve the Modelling of Machining and Cutting Processes
      Metal cutting is a fundamental process in industrial production. The fast and accurate on-line prediction of metal cutting processes is crucial for the Intelligent Manufacturing (IM). With the advent of high-speed computing, robust numerical algorithms and machine learning technology, computational modelling serves as a tool for not only accurate but also fast predicting the complex machining processes and understanding the complex physics. In this work, the machine learning based numerical model is developed for simulation of metal cutting processes.
      Leitung: C. Weißenfels, P. Wriggers
      Team: M.Sc. Dengpeng Huang
      Jahr: 2018
      Förderung: China Scholarship Council (CSC)
    • Physics-Informed Data-Driven Simulation
      This project investigates to what extent simulation with neural networks on the one hand and data-based empirical modeling on the other hand can be combined in a symbiotic manner. The ultimate goal is the generation of reliable models for complex dynamical systems known as digital twins.
      Leitung: H. Wessels, P. Wriggers
      Team: H. Wessels
      Jahr: 2020

    Finite element technology

    • Application of the Virtual Element Method to Non-Conforming Contact Interfaces
      When using standard Finite Elements the discretization is subject to limitations depending on the element geometry. In contrast to this the Virtual Element Method offers the possibility for elements with an arbitrary number of nodes and special geometries like non-convex polygons or hanging nodes. In this Project the application of the Virtual Elements to different problems is investigated. Here it is used to create an efficient contact discretization.
      Leitung: P. Wriggers
      Team: W.T. Rust
      Jahr: 2014
    • Large Deformation Cohesive-Zone Element for Fracture in Rubbery Polymers
      In this work, a 3D cohesive zone element is developed considering material and geometric nonlinearities and suitable for modeling large deformations and rotations.
      Leitung: P. Wriggers
      Team: A. B. Harish
      Jahr: 2015
    • The stress and fatigue analysis of the transportation line
      The conveyor of the production line in Salzgitter Flachstahl GmbH which carries the steel coils is going to be subjected to an extra load due to the bigger coil size. The objective is to do a structural analysis of the conveyor to see if the safety factor of structure is still in the allowable region. Since, the loading condition is naturally variable due to continuously feeding the moving conveyor with steel coils, a fatigue analysis is required in addition to an ordinary static analysis.
      Leitung: Peter Wriggers
      Team: Meisam Soleimani
      Jahr: 2018

Publikationen


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2023


Multiplicative, Non-Newtonian Viscoelasticity Models for Rubber Materials and Brain Tissues: Numerical Treatment and Comparative Studies. / Ricker, Alexander; Gierig, Meike; Wriggers, Peter.

in: Archives of Computational Methods in Engineering, Jahrgang 30, Nr. 5, 06.2023, S. 2889–2927.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

Systematic Fitting and Comparison of Hyperelastic Continuum Models for Elastomers. / Ricker, Alexander; Wriggers, Peter.

in: Archives of Computational Methods in Engineering, Jahrgang 30, Nr. 3, 04.2023, S. 2257-2288.

Publikation: Beitrag in FachzeitschriftÜbersichtsarbeitForschungPeer-Review

Tensor Calculus and Differential Geometry for Engineers : With Solved Exercises. / Sahraee, Shahab; Wriggers, Peter.

1. Aufl. Cham : Springer Nature Switzerland AG, 2023. 674 S.

Publikation: Buch/Bericht/Sammelwerk/KonferenzbandMonografieForschungPeer-Review

Mathematical modeling and numerical simulation of arterial dissection based on a novel surgeon’s view. / Soleimani, Meisam; Deo, Rohan; Hudobivnik, Blaz et al.

in: Biomechanics and Modeling in Mechanobiology, Jahrgang 22, Nr. 6, 12.2023, S. 2097-2116.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

Numerical and experimental investigation of multi-species bacterial co-aggregation. / Soleimani, Meisam; Szafranski, Szymon P.; Qu, Taoran et al.

in: Scientific reports, Jahrgang 13, Nr. 1, 11839, 22.07.2023.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

Elimination of the Stops Because of Failure of Nonlinear Solutions in Nonlinear Seismic Time History Analysis. / Soroushian, Aram; Wriggers, Peter.

in: Journal of Vibration Engineering and Technologies, 30.08.2023.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

Test of an Idea for Improving the Efficiency of Nonlinear Time History Analyses When Implemented in Seismic Analysis According to NZS 1170.5:2004. / Soroushian, Aram; Wriggers, Peter.

Recent Trends in Wave Mechanics and Vibrations: Proceedings of WMVC 2022. Hrsg. / Zuzana Dimitrovová; Rodrigo Gonçalves; Zuzana Dimitrovová; Paritosh Biswas; Tiago Silva. Cham : Springer Science and Business Media B.V., 2023. S. 107-114 (Mechanisms and Machine Science; Band 125 MMS).

Publikation: Beitrag in Buch/Bericht/Sammelwerk/KonferenzbandAufsatz in KonferenzbandForschungPeer-Review

Failure of high-speed bearing at cyclic impact-sliding contacts : Numerical and experimental analysis. / Wang, Che; Aldakheel, Fadi; Zhang, Chuanwei et al.

in: International Journal of Mechanical Sciences, Jahrgang 253, 108410, 01.09.2023.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

A locking free virtual element formulation for Timoshenko beams. / Wriggers, P.

in: Computer Methods in Applied Mechanics and Engineering, Jahrgang 417, 116234, 15.12.2023.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review

Virtual element formulation for gradient elasticity. / Wriggers, Peter; Hudobivnik, Blaž.

in: Acta Mechanica Sinica/Lixue Xuebao, Jahrgang 39, Nr. 4, 722306, 06.2023.

Publikation: Beitrag in FachzeitschriftArtikelForschungPeer-Review


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