* Viscoelasticity
Viscoalasticity is the theory of the time dependence of the deformation to tension ratio. Model treatment of viscoelasticity. Creep and stress relaxation. Operator equations. Viscoelasticity without models - relations between characteristic viscoelastic functions. Boltzmann`s superposition principle. Time-temperature superposition. Time, frequency and temperature dependence of viscoleastic functions. Master curves.
* Viscous materials
Newton`s and non-Newton`s viscous liquids. Equation of flow. Circulation of body liquids. Bingham`s liquid - an example of plastic liquid.
* Determination of the rheological properties of materials
How to find the proper rheological model to the investigated material. The overlook of the main experimental methods of viscoelasticity and rheometry will be given.
* Excersizes
The main methods of the evaluation of the viscoelastic measurements will be treated (e.g. the evaluation of the torsion pendulum measurements). How to find the optimum number of rheological model links for the given material. Which viscoelastic models are equivalent. Approximation methods of viscoelastic spectra evaluation from experimentally obtained viscoelastic functions.
The lecture is devoted to the problem how to find the proper rheological model for the investigated biological material. The bulk biomaterials exhibit mostly viscoelastic behaviour, flowing materials are complex non-Newtonian liquids.
Therefore, viscoelasticity and the theory of non- Newtonian liquids will be treated in more detail. The theory will be completed by exercises which are added to the lecture.