Course detail

Constitutive Equations for EM

FSI-RKI-AAcad. year: 2026/2027

Students are required to have knowledge of basic terms of theory of elasticity (stress and strain tensors, Hooke's law for multiaxial stress), as well as some basic terms of hydrodynamics (perfect, Newtonian and non-Newtonian liquids, viscosity) and thermodynamics (entropy, state equation of perfect gas, thermodynamic equilibrium). Fundamentals of FEM and basic skills in ANSYS program system are necessary. Thus the course is not suitable for bachelor students.

Language of instruction

English

Number of ECTS credits

6

Mode of study

Not applicable.

Guarantor

prof. Ing. Jiří Burša, Ph.D.

Department

Institute of Solid Mechanics, Mechatronics and Biomechanics (ÚMTMB)

Offered to foreign students

Of all faculties

Entry knowledge

Students are required to have knowledge of basic terms of theory of elasticity (stress and strain tensors, Hooke's law for multiaxial stress), as well as some basic terms of hydrodynamics (perfect, Newtonian and non-Newtonian liquids, viscosity) and thermodynamics (entropy, state equation of perfect gas, thermodynamic equilibrium). Fundamentals of FEM and basic skills in ANSYS program system are necessary. Thus the course is not suitable for bachelor students.

Rules for evaluation and completion of the course

The course-unit credit is awarded on condition of having actively participated in seminars and submitted an individual semester project. The exam is based on a written test of basic knowledge and defense of the individual semester project.
Attendance at practical training is obligatory. An apologized absence can be compensed by individual works controlled by the tutor.

Aims

The objective of the course is to provide students a comprehensive overview of constitutive dependencies of various types of matters, to interconnect their knowledge acquainted in various courses and fields (solid mechanics, hydromechanics, thermomechanics) and to make students familiar with practical applications of some of the constitutive models (in finite element program system ANSYS) useful in modelling of up-to-date materials (e.g. elastomers, plastics, composites with elastomer matrix, metals above the yield limit).
Students get an overview of mechanical properties and behaviour of matters and of possibilities of their mathematical description and modelling, especially of their time dependent as well as large strain behaviour. They will have a clear idea of their sophisticated application in design of machines and structures. Within the framework of capabilities of the used FE programme systems, they will be made familiar with the practical use of some of the more complex constitutive models (hyperelastic and non-elastic, isotropic and anisotropic) in stress-strain analyses.

Study aids

Not applicable.

Prerequisites and corequisites

Not applicable.

Basic literature

Články v odborných časopisech
Holzapfel G.A.: Nonlinear Solid Mechanics. Wiley, 2001.
Lemaitre J., Chaboche J.-L.: Mechanics of Solid Materials. Cambridge University Press, 1994.

Recommended reading

Němec I. a kol. Nelineární mechanika. VUTIUM, Brno, 2018

Classification of course in study plans

  • Programme N-IMB-P Master's

    specialization IME , 2 year of study, winter semester, compulsory

Type of course unit

 

Lecture

26 hod., optionally

Teacher / Lecturer

prof. Ing. Jiří Burša, Ph.D.

Syllabus

  1. Definition and overview of constitutive models in mechanics, constitutive models for individual states of matter, definition of deformation tensors.
  2. Stress and strain tensors under large strains, hyperelasticity model neo-Hooke.
  3. Mechanical tests of elastomers, polynomial hyperelastic models, predictive capability.
  4. Models Ogden, Arruda Boyce - entropic elasticity.
  5. Incremental modulus. Models of foams. Anisotropic hyperelasticity, pseudoinvariants.
  6. Non-elastic effects (Mullins). Plasticity criteria.
  7. Models of plastic flow, triaxiality factor, Lode parameter.
  8. Models of ductile fracture.
  9. Shape memory alloys
  10. Linear viscoelasticity – introduction
  11. Linear viscoelasticity – behaviour of models under static loading
  12. Linear viscoelasticity - dynamic behaviour, complex modulus
  13. Visco-hyperelasticity – model Bergstrom-Boyce, polar decomposition

Computer-assisted exercise

13 hod., compulsory

Teacher / Lecturer

prof. Ing. Jiří Burša, Ph.D.

Syllabus

  1. Experiment – elastomer testing

2.-3. FEM simulations of tests of elastomers

4.-5. Identification of constitutive models of elastomers

6.-7. Models of plasticity

8.-9. Models of anisotropic behaviour of elastomers and Mullins effect

10. Assessment of model parameters from experimental data

11.-12. Simulation of viscoelastic behaviour

13. Project formulation, course-unit credit.