M.Sc. Tobias Karl
- PhD Student / Research Assistant (ITM and ISTM)
- Room: 302.3
- Phone: +49 721 608-46898
- Fax: +49 721 608-44187
- tobias karl ∂does-not-exist.kit edu
Karlsruher Institut für Technologie (KIT)
Kaiserstraße 10
76131 Karlsruhe
Curriculum Vitae
| Since 02/2020 | PhD Student / Research Assistant, Institute of Engineering Mechanics, Chair for Continuum Mechanics, in cooperation with the Institute of Fluid Mechanics, Karlsruhe Institute of Technology (KIT) |
| 05/2019–11/2019 | Master thesis: "Direct Numerical Simulation of the Anisotropic Flow of Fiber-Suspensions" Institute of Fluid Mechanics in cooperation with the Institute of Engineering Mechanics, Chair for Continuum Mechanics, Karlsruhe Institute of Technology (KIT) |
| 04/2017–11/2019 | Studies of Mechanical Engineering (Master) with the specialization "Theoretical Mechanical Engineering",Karlsruhe Institute of Technology (KIT) Major Field: "Applied Mechanics" and "Fluid Mechanics", Master´s degree with distinction |
| 01/2017–03/2017 | Bachelor thesis: "Comparison and Evaluation of the Application of Multi-Layer-Models for the Simulation of Short-Fiber Reinforced Polymers in Combination with Organo Sheets", Institute of Engineering Mechanics, Chair for Continuum Mechanics, Karlsruhe Institute of Technology (KIT), in cooperation with Schaeffler Technologies AG & Co. KG, Herzogenaurach |
| 09/2016–12/2016 | Internship in modeling and simulation of fiber reinforced polymers, department "Advanced Materials", Schaeffler Technologies AG & Co KG, Herzogenaurach |
| 10/2013–03/2017 | Studies of Mechanical Engineering (Bachelor), Karlsruhe Institute of Technology (KIT), Major Field: "Continuum Mechanics and Strength of Materials" |
Field of Research
Fluid Mechanics and Homogenization of Anisotropic Flow Processes
During the processing of fiber-reinforced polymer materials by injection molding, the orientation of the fibers is determined by the flow field in the polymer melt. Since the orientation of the fibers significantly influences the anisotropic elastic properties of the manufactured part, a precise prediction of the orientation state at the end of mold filling is of great interest. The fibers induce an anisotropic viscous behavior of the fiber suspension that influences the flow field already during mold filling. One aim of the project is to investigate this so-called flow-fiber coupling with regard to the related effects on the predicted mechanical properties. The focus here is on micromechanical approaches for both the fiber-polymer melt and the composite.
In engineering practice, tensors are used to describe the orientation state, which are obtained by solving a suitable evolution equation. Since these equations are not closed, suitable approaches are required to close them. Another aim of the project is to develop closure methods that are both numerically efficient and accurately predict the evolution of the fiber orientation. In addition, closures are also used to predict the anisotropic viscous and elastic properties. The suitability of the developed closures in this context represents a further research objective.
Publications
Karl, T.; Schneider, M.; Böhlke, T.
2023. Journal of Non-Newtonian Fluid Mechanics, 318, 105049. doi:10.1016/j.jnnfm.2023.105049
Karl, T.; Zartmann, J.; Dalpke, S.; Gatti, D.; Frohnapfel, B.; Böhlke, T.
2023. Computational Mechanics, 71 (5), 991–1013. doi:10.1007/s00466-023-02277-z
Karl, T.; Böhlke, T.
2022. Archive of Applied Mechanics, 92 (12), 3695–3727. doi:10.1007/s00419-022-02257-4
Karl, T.; Gatti, D.; Frohnapfel, B.; Böhlke, T.
2021. Journal of Rheology, 65 (5), 999–1022. doi:10.1122/8.0000245
Karl, T.; Gatti, D.; Böhlke, T.; Frohnapfel, B.
2021. Acta mechanica, 232 (6), 2249–2268. doi:10.1007/s00707-020-02897-z
Talks
2023
Karl, T., Schneider, M., Böhlke, T.:
Implicit fiber orientation tensor closures
MathSEE Symposium on Applications of Mathematical Sciences, 27.-29.09.2023, Karlsruhe, Germany
Karl, T., Schneider, M., Böhlke, T.:
Fiber orientation tensor approximations based on an implicitly defined closure approach
International Conference on Composite Materials, 30.07.-04.08.2023, Belfast, Northern Ireland
Karl, T., Zartmann, J., Dalpke, S., Gatti, D., Frohnapfel, B., Böhlke, T.:
Mean-field based modeling of anisotropic viscosity and flow-fiber coupled mold-filling simulation of short-fiber suspensions
16th International Conference on Advanced Computational Engineering and Experimenting, 03.-07.07.2023, Heraklion, Crete
Karl, T., Böhlke, T.:
Flow-fiber coupling of mold-filling fiber suspension simulations based on anisotropic viscosity and mean-field modeling
IRTG/ICRG Summer School 2023, 20.06.2023, WissenschaftsForum Berlin, Germany
Böhlke, T., Karl, T., Sterr, B., Krause, M., Gajek, S.:
Skalenübergreifende kontinuumsmechanische Modellierung von Kompositen und Polykristallen
Abschiedskolloquium H. Altenbach, 12.05.2023, Otto-von-Guericke-Universität Magdeburg, Germany
Karl, T., Böhlke, T.:
Mean-Field basierte Fließsimulationen von Fasersuspensionen unter Berücksichtigung anisotroper Viskosität
Kolloquium der Materialwissenschaft und Werkstofftechnik, 31.01.2023, Universität des Saarlandes, Saarbrücken, Germany
2022
Karl, T., Gatti, D., Frohnapfel, B., Böhlke, T.:
Asymptotic fiber orientation states of the quadratically closed Folgar-Tucker equation and a subsequent closure improvement,
8th ECCOMAS Congress 2022, 05.-09.06.2022, Oslo, Norway
2021
Karl, T., Gatti, D., Frohnapfel, B., Böhlke, T.:
Coupled simulation of flow-induced viscous and elastic anisotropy of short-fiber reinforced composites,
91st GAMM Annual Meeting 2020@21, 15.-19.03.2021, Kassel, Germany
Courses
Winter Semester 2023/2024
- Übungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
- Rechnerübungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
Summer Semester 2023
- Vertretung ausgewählter Vorlesungen in Mathematische Methoden der Mikromechanik (MMM)
- Übungen zu Mathematische Methoden der Mikromechanik (MMM)
- Übungen zu Nonlinear Continuum Mechanics (NCM)
Winter Semester 2022/2023
- Übungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
- Rechnerübungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
Summer Semester 2022
- Übungen zu Mathematische Methoden der Mikromechanik (MMM)
- Übungen zu Nonlinear Continuum Mechanics (NCM)
Winter Semester 2021/2022
- Übungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
- Rechnerübungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
Summer Semester 2021
- Übungen zu Mathematische Methoden der Mikromechanik (MMM)
- Übungen zu Nonlinear Continuum Mechanics (NCM)
Winter Semester 2020/2021
- Übungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
- Rechnerübungen zu Kontinuumsmechanik der Festkörper und Fluide (KMFF)
Summer Semester 2020
- Rechnerübungen zu Einführung in die Finite-Elemente-Methode (FEM)
- Übungen zu Mathematische Methoden der Mikromechanik (MMM)