Instytutowe Seminarium Mechaniki im. W. Olszaka i A. Sawczuka

 kolor czcionki + kolor tła  = plan do 7 dni.

11:00, Sala: Aula im. Wacława Olszaka, piętro II
Krzysztof Falkowski
Maciej Henzel
Paulina Kurnyta-Mazurek
Military University of Technology, Faculty of Mechatronics and Aerospace

Magnetic suspension technology from Military University of Technology

Magnetic suspension technology was developed and commercialised in practice due to its advantages, such as no mechanical contact between the kinematic pair in various drives. This technology eliminates mechanical contact between the stator and the rotor, friction forces, small additional losses, etc. The magnetic suspension systems are classified into three categories: active, passive and non-bearing drives. Active magnetic suspensions use electromagnets to generate magnetic forces and require a closed-loop control system. Passive magnetic suspensions use permanent magnets, superconductors and conductors of various configurations to generate magnetic levitation forces. They do not require feedback control systems and they are simpler than the active systems. Compared to ordinary mechanical bearings, the magnetic bearings have several advantages, such as low mechanical vibrations level, no need for lubrication, high durability, no tribological wears and the ability to operate long time at high speed.

During the lecture, the magnetic suspension structure (active, passive and bearingless electric machines) will be presented. In particular, simulations and experimental studies of the magnetic linear guide and magnetic bearings dedicated to rotary machines will be shown. Finally, the doctoral dissertation on the advanced magnetic control system of a jet-engine rotor suspension system will be discussed.

2019-10-21 11:00, Sala: Aula im. Wacława Olszaka, piętro II
seminarium prowadzone przez prof. Tadeusza Burczyńskiego

Uroczyste seminarium naukowe poświęcone pamięci Profesora Wojciecha Krzysztofa Nowackiego (1938-2009)

Program Seminarium obejmuje:

* Powitanie gości i uczestników Seminarium - prof. Tadeusz Burczyński

* Wykład pt.: "Wspomnienie o Profesorze Wojciechu Krzysztofie Nowackim (1938-2009): życie i twórczość" - dr hab. Elżbieta Pieczyska

* Dyskusja: wystąpienia gości i uczestników:
Jak pamiętamy prof. Wojciecha K. Nowackiego?

* Zamknięcie Seminarium

* Poczęstunek

2019-10-14 11:00, Sala: Aula im. Wacława Olszaka, piętro II
prof. Wojciech Nasalski
Research Group of Nanophotonics

From Schrödinger and Maxwell equations to wave optics of exact vector twisted beams

It is well known that exact, nonparaxial solution to beam propagation can be obtained by successive corrections to the corresponding approximate, paraxial solution. This solution has then a form of infinite expansion of the beam field in powers of some expansion parameter. It appears however, that the exact solution to the problem can be formulated differently, without resorting to any field expansion or approximation. A final three-dimensional vector form of this solution is composed from a few independent scalar beam fields being exact solutions to Fock or Schrödinger parabolic equations. Elegant Laguerre-Gaussian beams of arbitrary order are taken as building blocks of this final solution. They span a space of square integrated functions and carry finite energy, linear and angular momenta densities along directions of their propagation. As such, they are especially suitable in analyses of beam propagation problems in free space or, in general, in any planar layered dielectric structure.

2019-10-07 11:00, Sala: Aula im. Wacława Olszaka, piętro II
prof. dr hab. inż. Henryk Petryk

A minimal gradient-enhancement of the classical continuum theory of crystal plasticity

A simple gradient-enhancement of the classical continuum theory of plasticity of single crystals has been proposed for incorporating size effects in a manner consistent with phenomenological laws established in materials science. A missing term in the standard hardening rate-equation has been derived which includes a natural internal length scale expressed in a closed form through standard parameters. In result, by this simple enhancement of the classical theory of plasticity, no extra assumption is needed to predict size effects. A surprising agreement with experimental observations of the spherical indentation in a Cu single crystal was found.