### Inhalt des Dokuments

# Univ.-Prof. Dr.-Ing. habil. Sandra Klinge

Technische Universität Berlin

Institut für Mechanik

FG Strukturmechanik und Strukturberechnung

Sekr. C 8-3, M 126

Straße des 17. Juni 135

10623 Berlin

Tel.: +49 (0)30 314-23456

Email: sandra.klinge(at)tu-berlin.de

Sekretariat: Anke Happ

Dr.-Ing. habil. Sandra Klinge has been a professor for "Structural Mechanics and Structural Computation" (SMB) at the Faculty of Transportation and Machine Systems at TU Berlin since July of this year. The focus of her scientific work is the development of numerical methods for the simulation of heterogeneous materials. In this context, she has focused on the application of the multiscale finite element method to solve direct and inverse problems. The large computational effort, the strong nonconvexity, the determination of the global solution are only some of the issues characteristic for this research area.

Ms. Klinge completed the international master course "Comp-Eng" as a DAAD scholarship holder at the Ruhr-Universität Bochum. At the same university she did her doctorate and habilitation. Subsequently, she established her own research group as junior professor in "Computational Engineering" at the TU Dortmund University. Ms. Klinge has numerous international collaborations especially in the field of biomechanics and of simulation of metal forming processes. At TU Berlin, Ms. Klinge will work on the further development of numerical methods such as statistical homogenization, isogeometric analysis and machine learning as well as on their practical application. TU Berlin offers an ideal environment for work at these topics due to its diversity, large number of excellent students and strong international scientific network.

### Modeling of composite materials

The main topic of the research work is concerned with the theory of homogenization and its application to statistically uniform materials, a group of materials for which a so-called representative volume element (RVE) can be defined. The approach defines micro- and macro boundary value problems (BVP) which are related to each other by using the principle of the volume average and the Hill-Mandel macrohomogeneity condition. The latter requires the equality of the macropower with the volume average of the micropower and is used to define the boundary conditions for the RVE.

### Parameter identification - Inverse FE2 analysis

In many cases, the microstructure of composite materials is not known and cannot directly be accessed such that an inverse analysis is necessary for its investigation. This approach requires the implementation of two tools: an optimization method for the minimization of the error problem and a mechanical approach for the solution of the direct problem, i.e. the simulation of composite materials. One particular choice deals with the combination of the Levenberg–Marquardt method with the multiscale finite element method. The typical examples in this field investigate the elastic parameters for multi-phase materials. The sensitivity with respect to the initial guess and the influence of the measurement error are common problems to determine a unique solution.

### Further topics:

- Simulation of polymers
- Modeling of metal forming processes
- Simulation of diffusional processes
- Investigation of cancellous bone
- Simulation of endocytosis (viral entry into a cell)

### New Book: Applications of Homogenization Theory to the Study of Mineralized Tissue

R. P. Gilbert, A. Vasilic, S. Klinge, A. Panchenko and K. Hackl

ISBN-13: 978-1584887911

ISBN-10: 1584887915

Applications of Homogenization Theory to the Study of Mineralized Tissue functions as an introduction to the theory of homogenization. At the same time, the book explains how to apply the theory to various application problems in biology, physics and engineering. This useful research monograph is suitable for applied mathematicians, engineers and geophysicists. As for students and instructors, it is a well-rounded and comprehensive text on the topic of homogenization for graduate level courses or special mathematics classes.

Features:

- Covers applications in both geophysics and biology,
- Includes recent results not found in classical books on the topic,
- Focuses on evolutionary kinds of problems; there is little overlap with books dealing with variational methods and T-convergence,
- Includes new results where the G-limits have different structures from the initial operators.

### Publications in journals (reviewed)

- S. Aygün, T. Wiegold and S. Klinge. Coupling of the phase field approach to the Armstrong-Frederick model for the simulation of ductile damage under cyclic load.
*Int. J. Plast.*, 143:103021, 2021. - D. C. Haspinger, S. Klinge and G. A. Holzapfel. Numerical analysis of the impact of cytoskeletal actin filament density alterations onto the diffusive vesicle-mediated cell transport.
*PLoS Comput. Biol.*, 17(5):e1008784, 2021. - T. Wiegold, S. Klinge, R. P. Gilbert and G. A. Holzapfel. Numerical simulation of the viral entry into a cell driven by receptor diffusion.
*Comput. Math. Appl.*, 84:224–243, 2021. - S. Aygün and S. Klinge. Thermomechanical Modeling of Microstructure Evolution Caused by Strain-Induced Crystallization.
*Polymers*, 12 (11):2575, 2020. - S. Aygün and S. Klinge. Continuum mechanical modeling of strain-induced crystallization in polymers.
*Int. J. Solids Struct.*, 196–197:129–139, 2020. - S. Siddique, M. Awd, T. Wiegold, S. Klinge and F. Walther. Simulation of cyclic deformation behavior of selective laser melted and hybrid-manufactured aluminum alloys using the phase-field method.
*Appl. Sci.*, 8(10):1948, 2018. - S. Klinge, S. Aygün, R. P. Gilbert and G. A. Holzapfel. Multiscale FEM simulations of cross-linked actin network embedded in cytosol with the focus on the filament orientation.
*Int. J. Numer. Methods Biomed. Eng.*, 34(7):e2993, 2018. - S. Klinge and K. Hackl. Application of the Multiscale FEM to the Determination of Macroscopic Deformations Caused by Dissolution-precipitation Creep.
*Int. J. Multiscale Comp. Eng.*, 14(2):95–111, 2016. - S. Klinge, K. Hackl and J. Renner. Mechanical Model for Dissolution-Precipitation Creep Based on the Principle of Minimizing Dissipation Potential.
*Proc. Roy. Soc. A*, 471:2180–2202, 2015. - S. Klinge and P. Steinmann. Inverse Analysis for Heterogeneous Materials and its Application to Viscoelastic Curing Polymers.
*Comput. Mech.*, 55:603–615, 2015. - S. Klinge. Determination of the Geometry of the RVE for Cancellous Bone by Using the Effective Complex Shear Modulus,
*Biomechan. Model. Mechanobiol.*, 12(2):401–412, 2013. - S. Klinge, K. Hackl and R.P. Gilbert. Investigation of the Influence of Reflection on the Attenuation of Cancellous Bone.
*Biomechan. Model. Mechanobiol.*, 12(1):185–199, 2013. - S. Klinge, A. Bartels and P. Steinmann. The Multiscale Approach to the Curing of Polymers Incorporating Viscous and Shrinkage Effects.
*Int. J. Solid. Struct.*, 49:3883–3900, 2012. - S. Klinge, A. Bartels and P. Steinmann. Modeling of Curing Processes Based on a Multi-Field Potential. Single- and Multiscale Aspects.
*Int. J. Solid. Struct.*, 49:2320–2333, 2012. - S. Klinge and K. Hackl. Contribution of the Reflection to the Attenuation Properties of Cancellous Bone.
*Complex Var. Elliptic Equ.*, 57(2–4):425–436, 2012. - S. Klinge. Inverse Analysis for Multiphase Nonlinear Composites with Random Microstructure.
*Int. J. Multiscale Comp. Eng.*, 10(4):361–373, 2012. - S. Klinge. Parameter Identification for Two-Phase Nonlinear Composites.
*Comput. Struct.*, 108–109:118–124, 2012. - S. Klinge and K. Hackl. Application of the Multiscale FEM to the Modeling of Nonlinear Composites with a Random Microstructure.
*Int. J. Multiscale Comp. Eng.*, 10(3):213–227, 2012. - S. Ilic, K. Hackl and R. P. Gilbert. Application of a Biphasic Representative Volume Element to the Simulation of Wave Propagation through Cancellous Bone.
*J. Comput. Acoust.*, 19(2):111–138, 2011. - S. Ilic, K. Hackl and R.P. Gilbert. Application of the Multiscale FEM to the Modeling of Cancellous Bone.
*Biomechan. Model. Mechanobiol.*, 9(1):87–102, 2010. - S. Ilic and K. Hackl. Application of the Multiscale FEM to the Modeling of Nonlinear Multiphase Materials.
*J. Theor. Appl. Mech.*, 47:537–551, 2009. - K. Hackl and S. Ilic. Solution-precipitation Creep – Continuum Mechanical Formulation and Micromechanical Modelling.
*Arch. Appl. Mech.*, 74:773–779, 2005.

### Publications in journals

- S. Klinge, T. Wiegold, S. Aygün, R. P. Gilbert and G. A. Holzapfel. Numerical modeling of the receptor driven endocytosis.
*PAMM*, 21(1):e202100142, 2021. - S. Aygün and S. Klinge. Multiscale modeling of calcified hydrogel networks.
*PAMM*, 21(1):e202100115, 2021. - T. Wiegold, S. Aygün and S. Klinge. Numerical simulation of low cycle fatigue behavior, combining the phase-field method and the Armstrong-Frederick model.
*PAMM*, 21(1):e202100111, 2021. - S. Aygün and S. Klinge. Study of stochastic aspects in the modeling of the strain-induced crystallization in unfilled polymers.
*PAMM*, 20(1):e202000031, 2021. - S. Klinge, T. Wiegold, S. Aygün, R. P. Gilbert and G. A. Holzapfel. On the mechanical modeling of cell components.
*PAMM*, 20(1):e202000129, 2021. - T. Wiegold and S. Klinge. Numerical simulation of cyclic deformation behavior of SLM-manufactured aluminum alloys.
*PAMM*, 20(1):e202000181. - S. Aygün and S. Klinge. Coupled thermomechanical model for strain-induced crystallization in polymers.
*PAMM*, 19(1):e201900342, 2019. - V. Fohrmeister, S. Klinge and J. Mosler. On the implementation of rate-independent gradient-enhanced crystal plasticity theory.
*PAMM*, 19(1):e201900461, 2019. - T. Wiegold, S. Klinge, G. A. Holzapfel and R. P. Gilbert. Computational Modeling of Adhesive Contact between a Virus and a Cell during Receptor Driven Endocytosis.
*PAMM*, 19(1):e201900161, 2019. - S. Aygün and S. Klinge. Study of the microstructure evolution caused by the strain‐induced crystallization in polymers.
*PAMM*, 18(1):e201800224, 2018. - S. Klinge, S. Aygün and M. Bambach. Extended Simulations of the Roll Bonding Process.
*PAMM*, 18(1):e201800257, 2018. - T. Wiegold, S. Klinge, S. Aygün, R. P. Gilbert and G. A. Holzapfel. Viscoelasticity of cross‐linked actin network embedded in cytosol.
*PAMM*, 18(1):e201800151, 2018. - S. Aygün and S. Klinge. Mechanical Modeling of the Strain-Induced-Crystallization in Polymers.
*PAMM*, 17(1):389–390, 2017. - M. Bambach and S. Klinge. Consistency of Dynamic Recrystallization Models from the Perspective of Physical Metallurgy and Continuum Mechanics.
*PAMM*, 17(1):395–396, 2017. - S. Klinge, T. Wiegold, G. A. Holzapfel and R. P. Gilbert. The Influence of Binder Mobility to the Viral Entry Driven by the Receptor Diffusion.
*PAMM*, 17(1):197–198, 2017. - S. Klinge, S. Aygün, J. Mosler and G. A. Holzapfel. Cross-linked actin networks: Micro- and macroscopic effects.
*PAMM*, 16(1):93–94, 2016. - S. Klinge and P. Steinmann. Determination of Material Parameters Corresponding to Viscoelastic Curing Polymers.
*PAMM*, 15(1):315–316, 2015. - S. Klinge, A. Bartels, K. Hackl and P. Steinmann. Viscoelastic Effects and Shrinkage as the Accompanying Phenomena of the Curing of Polymers. Single- and Multiscale Effects.
*PAMM*, 12(1):435–436, 2012. - A. Bartels, S. Klinge, K. Hackl and P. Steinmann. Single and Multiscale Aspects of the Modeling of Curing Polymers.
*PAMM*, 12(1):303–304, 2012. - C. Günther, S. Ilic and K. Hackl. Application of the Green Tensor to the Modeling of Solution-Precipitation Creep.
*PAMM*, 11:375–376, 2011. - S. Ilic and K. Hackl. Simulation of Diffusional Processes from the Microscopic and Macroscopic Point of View.
*PAMM*, 9:429–430, 2009. - S. Ilic, K. Hackl and R. P. Gilbert. Effective Material Parameters of Bone.
*PAMM*, 8:10175–10176, 2008. - S. Ilic, K. Hackl and R. P. Gilbert. Estimation of Material Properties of Cancellous Bone Using Multiscale FEM.
*PAMM*, 7:4020015–4020016, 2007. - S. Ilic and K. Hackl. Multiscale FEM in Modelling of Solution-precipitation Creep.
*PAMM*, 6:483–484, 2006. - S. Ilic and K. Hackl. Solution-precipitation Creep – Micromechanical Modelling and Numerical Results.
*PAMM*, 5:277–278, 2005. - S. Ilic and K. Hackl. Homogenisation of Random Composite Via the Multiscale Finite Element Method.
*PAMM*, 4:326–327, 2004.

### Contributions in books and in proceeding books

- S. Aygün and S. Klinge. Thermodynamical model for strain-induced crystallization in polymers
*. 25th International Congress of Theoretical and Applied Mechanics – Book of Abstracts*, 1:2298–2299, 2021. - S. Aygün and S. Klinge. Modeling the thermomechanical behavior of strain-induced crystallization in unfilled polymers.
*Proceedings of the 8th GACM Colloquium on Computational Mechanics*, 151–154, 2019. - T. Wiegold, S. Klinge, R. P. Gilbert and G. A. Holzapfel. Numerical simulation of the viral entry into a cell by receptor driven endocytosis.
*Proceedings of the 8th GACM Colloquium on Computational Mechanics*, 401–404. - M. Awd, S. Siddique, J. Johannsen, T. Wiegold, S. Klinge, C. Emmelmann and F. Walther. Quality assurance of additively manufactured alloys for aerospace industry by non-destructive testing and numerical modeling.
*Proceedings of the 10th International Conference on Non-destructive Testing in Aero-space*, 1–10, 2018. - S. Aygün, S. Klinge and S. Govindjee. Continuum Mechanical Modeling of Strain-Induced Crystallization in Polymers.
*Proceedings of the 7th GACM Colloquium on Computational Mechanics*, 579–582, 2017. - R. P. Gilbert, A. Vasilic and S. Ilic. Homogenization Theories and Inverse Problems, Bone Quantitative Ultrasound. P. Laugier and G. Haiat (Eds.),
*Springer*, 229-264, 2011. - S. Ilic and K. Hackl. Inverse Problems in the Modelling of Composite Materials.
*Proceedings of the Seventh International Conference on Engineering Computational Technology (ECT)*, B.H.V. Topping, J.M.Adam, F.J. Pallares, R. Bru and M.L. Romero (Eds.), Civil-Comp Press, Stirlingshire, Scotland, Paper 122, 2010. - R. P. Gilbert, K. Hackl and S. Ilic. Investigation of the Acoustic Properties of the Cancellous Bone.
*Progress in Analysis and its Applications*, M. Ruzhansky and J. Wirth (Eds.), World Scientific, 570—5577, 2010. - S. Ilic and K. Hackl. Solution-precipitation Creep - Extended FE Implementation, Variational Concepts with Application to the Mechanics of Materials.
*Springer*, 105—116, 2010. - K. Hackl, S. Ilic and R. P. Gilbert. Multiscale Modeling for Cancellous Bone by Using Shell Elements, Shell Structures: Theory and Applications. W. Pietrasckiewicz and I. Kreja (Eds.),
*Taylor & Francis Group CRC Press*, 249–252, 2009. - S. Ilic and K. Hackl. Application of the Multiscale FEM to the Modeling of Heterogeneous Materials.
*Proceedings of the first Seminar on the Mechanics of Multifunctional Materials*,

J. Schröder and D. Lupascu and D. Balzani (Eds.), University of Duisburg-Essen, 47–51, 2007.