### İLKER TEMİZER

#### Professor, Chair

#### Address

Department of Mechanical Engineering

Bilkent University

06800 Bilkent, Ankara

#### Office

EA116

#### Phone

+90 (312) 290-1045

### BIOGRAPHY

İlker Temizer received his B.S. degree (2001) from Boğaziçi University and his M.S. (2003) and Ph.D. (2005) degrees from the University of California, Berkeley in Mechanical Engineering. Subsequently, he joined the Institute of Continuum Mechanics of the Leibniz University at Hannover as a post-doctoral researcher where he held teaching and research responsibilities in addition to the leadership of a junior research group. Since September 2010, he is a faculty member at Bilkent University. He leads the Computational Multiscale Mechanics Laboratory (CMML) where the research efforts are focused on the theoretical and numerical aspects of computational mechanics that are associated with multiscale-multiphysics modeling strategies for heterogeneous materials and interfaces.

Curriculum Vitae | Web of Science | ORCID | Google Scholar

### EDUCATION

Ph.D., Mechanical Engineering, University of California, Berkeley (2005)

M.S., Mechanical Engineering, University of California, Berkeley (2003)

B.S., Mechanical Engineering, Boğaziçi University (2001)

### RESEARCH

Since the advent of powerful and easily accessible computer infrastructure, computational science and engineering has introduced revolutionary tools and approaches into diverse fields ranging from physics, chemistry and biology to mechanics, electronics and medicine. Through both fundamental numerical algorithms which are efficient and fast as well as applied software with impressive predictive capability, computational methods have reduced reliance on laboratory experimentation, thereby offering a rapid and accurate assessment strategy with high reliability.

My research in the field of **computational mechanics** over the past 10 years has contributed to the ongoing shift of emphasis from experiment to computation in the field of mechanics, with a particular focus on problems which are governed by multiple interacting nonlinear physical phenomena that occur over multiple temporal and spatial scales. Such **multiscale and multiphysics problems** inherently exist in the modeling of **heterogeneous materials and** **interfaces** where, historically, the models are constructed as mathematical representations of macroscopic observations that are the manifestations of entangled microscopic events. The goal of my research is to gain insight into complex macroscopic physics by probing the governing microscopic mechanisms through novel computational multiscale frameworks. Contrary to phenomenological modeling that relies on experimentation, I concentrate on lower-scale models which capture the essential physics and which interact to automatically display rich upper-scale behavior that is predicted through mathematical or computational homogenization.

The major theme in my research has been the unification of the multiscale treatment of materials and interfaces in the context of nonlinear thermomechanics. In theoretical and numerical interaction with applied mathematics, I have contributed to the development of thermodynamically and algorithmically consistent homogenization frameworks embedded in novel nonlinear finite/discrete element methods. With applications ranging from polymeric composites and biological tissue to rough and granular contact interfaces, my prior and ongoing research efforts can be categorized in the following three interactive **research thrust areas (RTA):****(RTA1)** Multiphysics Computational Homogenization of Materials**(RTA2)** Multiphysics Computational Homogenization of Interfaces**(RTA3)** Isogeometric Computational Contact Mechanics

**LECTURE NOTES ON MICROMECHANICS**

The collection MICROMECHANICS provides:

(1) **lecture notes** on the analysis of heterogeneous materials and homogenization, as well as

(2) **Fortran and MATLAB codes** that accompany the computational exercises in Part II of the notes.

The aim of these lecture notes is to introduce the students to the concepts of micromechanical modeling and analysis. The content of the subject is classically mostly analytical. In these notes, computational aspects are also emphasized due to the wide range of micromechanical problems that can be tackled with robust numerical methods. A significant portion of the figures appearing in the lecture notes were generated using the codes provided.

Instructions on using the codes are given in the README file of each exercise. The MATLAB codes are used for visualization, evaluating analytical bounds and estimates as well as in the generation of digital and particulate microstructures. The Fortran codes are based on the finite element method in linear and nonlinear settings, the latter capable of finite deformations with damage. The underlying theory is outlined in the lecture notes.

**LECTURE VIDEOS ON SOLID MECHANICS**

Series of lectures are available online at the Bilkent University YouTube channel for the following two elective courses:

(1) **ME 446** – Applications of Solid Mechanics (undergraduate-level course)

(2) **ME 550** – Continuum Mechanics (graduate-level course)

The following YouTube channel contains the lecture-laboratory-recitation videos of a 2nd-year core curriculum course:

(3) **ME 232** - Mechanics and Materials II (undergraduate-level course)

### PROJECTS

- Isogeometric Computational Contact Mechanics (RTA3)
- Multiphysics Computational Homogenization of Interfaces (RTA2)
- Multiphysics Computational Homogenization of Materials (RTA1)
- Granular Contact Interfaces with Non-Circular Particles
- Hierarchical Isogeometric Analysis Technology and Computational Contact Mechanics
- Multiscale Analysis and Micro-Texture Design for Lubrication Interfaces
- Multiscale Fluid-Solid Interaction in Heterogeneous Materials and Interfaces
- Thermomechanical homogenization techniques for metallic and polymeric contact interfaces

### RELATED PUBLICATIONS

- Yalçın, M. A., Temizer, İ. (2023). "Hybrid Finite Element / Multipole Expansion Method for Atomic Kohn-Sham Density Functional Theory Calculations",
*Computer Physics Communications*, v.286 p.108658, Full Text - Mozafari, F., Temizer, İ. (2023). "Computational homogenization of fatigue in additively manufactured microlattice structures",
*Computational Mechanics*, v.71 p.367-384, Full Text - Karaca, K., Temizer, İ. (2023). "Variationally consistent Hellmann-Feynman forces in the finite element formulation of Kohn-Sham density functional theory",
*Computer Methods in Applied Mechanics and Engineering*, v.403 p.115674, Full Text - Temizer, İ. (2021). "Radial and Three-Dimensional Nonlocal Pseudopotential Calculations in Gradient-Corrected Kohn–Sham Density Functional Theory Based on Higher-Order Finite Element Methods",
*Computer Methods in Applied Mechanics and Engineering*, v.386 p.114094, Full Text - Temizer, İ., Motamarri, P., Gavini, V. (2020). "NURBS-based Non-Periodic Finite Element Framework for Kohn-Sham Density Functional Theory Calculations",
*Journal of Computational Physics*, v.410 p.109364, Full Text - Özcan, M., Çakmakcı, M., Temizer, İ. (2020). "Smart Composites with Tunable Stress-Strain Curves",
*Computational Mechanics*, v.65 p.375-394, Full Text - Çakal, B.A., Temizer, İ., Terada, K., Kato, J. (2019). "Microscopic Design and Optimization of Hydrodynamically Lubricated Dissipative Interfaces",
*International Journal for Numerical Methods in Engineering*, v.120 p.153-178, Full Text - Nishi, S., Terada, K., Temizer, İ. (2019). "Isogeometric analysis for numerical plate testing of dry woven fabrics involving frictional contact at meso-scale",
*Computational Mechanics*, v.64 p.211-229, Full Text - Waseem, A., Guilleminot, J., Temizer, İ. (2017). "Stochastic Multiscale Analysis in Hydrodynamic Lubrication",
*International Journal for Numerical Methods in Engineering*, v.112 p.1070-1093, Full Text - Waseem, A., Temizer, İ., Kato, J., Terada, K. (2017). "Micro-Texture Design and Optimization in Hydrodynamic Lubrication via Two-Scale Analysis",
*Structural and Multidisciplinary Optimization*, v.56 p.227-248, Full Text - Yıldıran, İ.N., Temizer, İ., Çetin, B. (2017). "Homogenization in Hydrodynamic Lubrication: Microscopic Regimes and Re-Entrant Textures",
*Journal of Tribology*, v.140 p.011701(1-19), Full Text - Kılıç, K.İ., Temizer, İ. (2016). "Tuning Macroscopic Sliding Friction at Soft Contact Interfaces: Interaction of Bulk and Surface Heterogeneities",
*Tribology International*, v.104 p.83-97, Full Text - Waseem, A., Temizer, İ., Kato, J., Terada, K. (2016). "Homogenization-Based Design of Surface Textures in Hydrodynamic Lubrication",
*International Journal for Numerical Methods in Engineering*, v.108 p.1427-1450, Full Text - Temizer, İ., Stupkiewicz, S. (2016). "Formulation of the Reynolds Equation on a Time-Dependent Lubrication Surface",
*Proceedings of the Royal Society A*, v.472 p.20160032, Full Text - Temizer, İ. (2016). "Sliding Friction Across the Scales: Thermomechanical Interactions and Dissipation Partitioning",
*Journal of the Mechanics and Physics of Solids*, v.89 p.126-148, Full Text - Hesch, C., Franke, M., Dittmann, M., Temizer, İ. (2016). "Hierarchical NURBS and a higher-order phase-field approach to fracture for finite-deformation contact problems",
*Computer Methods in Applied Mechanics and Engineering*, v.301 p.242-258, Full Text - Temizer, İ., Hesch, C. (2016). "Hierarchical NURBS in Frictionless Contact",
*Computer Methods in Applied Mechanics and Engineering*, v.299 p.161-186, Full Text - Kabacaoğlu, G., Temizer, İ. (2015). "Homogenization of Soft Interfaces in Time-Dependent Hydrodynamic Lubrication",
*Computational Mechanics*, v.56 p.421-441, Full Text - Temizer, İ. (2014). "Computational Homogenization of Soft Matter Friction: Isogeometric Framework and Elastic Boundary Layers",
*International Journal for Numerical Methods in Engineering*, v.100 p.953-981, Full Text - Temizer, İ., Abdalla, M., Gürdal, Z. (2014). "An Interior Point Method for Isogeometric Contact",
*Computer Methods in Applied Mechanics and Engineering*, v.276 p.589-611, Full Text - Dittmann, M., Franke, M., Temizer, İ., Hesch, C. (2014). "Isogeometric analysis and thermomechanical mortar contact problems",
*Computer Methods in Applied Mechanics and Engineering*, v.274 p.192-212, Full Text - Wu, T., Temizer, İ., Wriggers, P. (2014). "Multiscale Hydro-Thermo-Chemo-Mechanical Coupling: Application to Alkali-Silica Reaction",
*Computational Materials Science*, v.84 p.381-395, Full Text - Temizer, İ. (2014). "Multiscale Thermomechanical Contact: Computational Homogenization with Isogeometric Analysis",
*International Journal for Numerical Methods in Engineering*, v.97 p.582-607, Full Text - Temizer, İ. (2013). "Granular Contact Interfaces with Non-Circular Particles",
*Tribology International*, v.67 p.229–239, Full Text - Temizer, İ., Wu, T., Wriggers, P. (2013). "On the Optimality of the Window Method in Computational Homogenization",
*International Journal of Engineering Science*, v.64 p.66-73, Full Text - Temizer, İ. (2013). "A Mixed Formulation of Mortar-Based Contact with Friction",
*Computer Methods in Applied Mechanics and Engineering*, v.255 p.183-195, Full Text - Wu, T., Temizer, İ., Wriggers, P. (2013). "Computational Thermal Homogenization of Concrete",
*Cement & Concrete Composites*, v.35 p.59-70, Full Text - Temizer, İ. (2012). "A Mixed Formulation of Mortar-Based Frictionless Contact",
*Computer Methods in Applied Mechanics and Engineering*, v.223-224 p.173-185, Full Text - Budt, M., Temizer, İ., Wriggers, P. (2012). "A Computational Homogenization Framework for Soft Elastohydrodynamic Lubrication",
*Computational Mechanics*, v.49 p.749-767, Full Text - Temizer, İ. (2012). "On the Asymptotic Expansion Treatment of Two-Scale Finite Thermoelasticity.",
*International Journal of Engineering Science*, v.53 p.74-84, Full Text - Temizer, İ., Wriggers, P., Hughes, T. (2012). "Three-Dimensional Mortar-Based Frictional Contact Treatment in Isogeometric Analysis with NURBS",
*Computer Methods in Applied Mechanics and Engineering*, v.209-212 p.115-128, Full Text - De Lorenzis, L., Temizer, İ., Wriggers, P., Zavarise, G. (2011). "A large deformation frictional contact formulation using NURBS-based isogeometric analysis",
*International Journal for Numerical Methods in Engineering*, v.87 p.1278-1300, Full Text - Temizer, İ., Wriggers, P., Hughes, T. (2011). "Contact Treatment in Isogeometric Analysis with NURBS",
*Computer Methods in Applied Mechanics and Engineering*, v.200 p.1100-1112, Full Text - Temizer, İ., Wriggers, P. (2011). "An adaptive multiscale resolution strategy for the finite deformation analysis of microheterogeneous structures",
*Computer Methods in Applied Mechanics and Engineering*, v.200 p.2639-2661, Full Text - Temizer, İ., Wriggers, P. (2011). "Homogenization in Finite Thermoelasticity",
*Journal of the Mechanics and Physics of Solids*, v.59 p.344–372, Full Text - Temizer, İ. (2011). "Thermomechanical Contact Homogenization with Random Rough Surfaces and Microscopic Contact Resistance",
*Tribology International*, v.44 p.114-124, Full Text - Ma, J., Temizer, İ., Wriggers, P. (2011). "Random homogenization analysis in linear elasticity based on analytical bounds and estimates",
*International Journal of Solids and Structures*, v.48(2) p.280-291, Full Text - Temizer, İ., Wriggers, P. (2010). "A micromechanically motivated higher-order continuum formulation of linear thermal conduction",
*Zeitschrift für Angewandte Mathematik und Mechanik*, v.90(10-11) p.768-782, Full Text - Temizer, İ., Wriggers, P. (2010). "Thermal contact conductance characterization via computational contact homogenization: A finite deformation theory framework",
*International Journal for Numerical Methods in Engineering*, v.83(1) p.24-58, Full Text - Temizer, İ., Wriggers, P. (2010). "Inelastic analysis of granular interfaces via computational contact homogenization",
*International Journal for Numerical Methods in Engineering*, v.84(8) p.883-915, Full Text - Temizer, İ., Wriggers, P. (2008). "On a mass conservation criterion in homogenization",
*Journal of Applied Mechanics, Transactions ASME*, v.75 p.054503, Full Text - Temizer, İ., Wriggers, P. (2008). "A multiscale contact homogenization technique for the modeling of third bodies in the contact interface",
*Computer Methods in Applied Mechanics and Engineering*, v.198(3-4) p.377-396, Full Text - Temizer, İ., Wriggers, P. (2008). "On the computation of the macroscopic tangent for multiscale volumetric homogenization problems",
*Computer Methods in Applied Mechanics and Engineering*, v.198(3-4) p.495-510, Full Text - Temizer, İ., Wriggers, P. (2007). "An adaptive method for homogenization in orthotropic nonlinear elasticity",
*Computer Methods in Applied Mechanics and Engineering*, v.196(35-36) p.3409-3423, Full Text - Temizer, İ., Zohdi, T.I. (2007). "A numerical method for homogenization in non-linear elasticity",
*Computational Mechanics*, v.40(2) p.281-298, Full Text - Temizer, İ., Zohdi, T.I. (2005). "Agglomeration and refragmentation in microscale granular flows",
*International Journal of Fracture*, v.131(3) p.L37-L44, Full Text