Für elastische Balken mit Piezoaktuatoren werden flachheitsbasierte Randsteuerungen entworfen, die eine Positionierung in endlicher Einstellzeit gestatten. Dabei werden sowohl Euler-Bernoulli-Balken als auch Timoshenko-Balken untersucht. Steuerungen für Balken mit mehreren Piezoaktuatoren werden durch Superposition berechnet. Die Methoden werden durch die Ergebnisse von Simulationen und eines E...

We consider dynamics of the one-dimensional Mindlin-Timoshenko model for beams with a nonlinear external forces and a boundary damping mechanism. We investigate existence and uniqueness of strong and weak solution. We also study the boundary stabilization of the solution, i.e., we prove that the energy of every solution decays exponentially as t → ∞. AMS Subject Classifications. 35L70, 35B40, 7...

In this article, turbulent flow heat transfer in the air gap between rotor and stator of a generator under nonhomogeneous heat flux is studied experimentally. The rotor consists of four symmetrical triangular grooves. The stator surface is smooth and does not include any grooves. The relative heat flux between the rotor and the stator is 1 to 3. Temperature and heat flux are measured locally at...

Crack fault of rotor is one of the most prominent problems faced by magnetic bearing rotor system. In order to improve the safety performance of this kind of machinery, it is necessary to research the vibration characteristics of magnetic bearing cracked rotor system. In this paper, the stiffness model of the crack shaft element was established by the strain energy release rate (SERR) theory. T...

This article presents an analysis of free vibration of elastically supported Timoshenko beams by using the spectral element method. The governing partial differential equation is elaborated to formulate the spectral stiffness matrix. Effectively, the non classical end boundary conditions of the beam are the primordial task to calibrate the phenomenon of the Timoshenko beam-soil foundation inter...

in this paper, eringen’s nonlocal elasticity and timoshenko beam theories are implemented to analyze the bending vibration for non-uniform nano-beams.  the governing equations and the boundary conditions are derived using hamilton’s principle. a generalized differential quadrature method (gdqm) is utilized for solving the governing equations of non-uniform timoshenko nano-beam for pinned-pinned...

In this paper, a relatively new method, namely variational iteration method (VIM), is developed for free vibration analysis of a Timoshenko beam with different boundary conditions. In the VIM, an appropriate Lagrange multiplier is first chosen according to order of the governing differential equation of the boundary value problem, and then an iteration process is used till the desired accuracy ...

In this article free vibration of a Timoshenko nanobeam with variable cross-section is investigated using nonlocal elasticity theory within the scope of continuum mechanics. Small scale effects are modelled after Eringen’s nonlocal elasticity theory while the non-uniformity is presented by exponentially varying width through the beam length with constant thickness. Analytical solution is achiev...

The coupled dynamic model of the intermediate and tail gearboxes’ spiral bevel gear-oblique shaft-laminated membrane coupling was established by employing hybrid modeling method finite element lumped mass. Among them, equation shaft constructed Timoshenko beam; gears were derived theoretically lumped-mass method, where effects time-varying meshing stiffness, transmission error, external imbalan...

The effects of lobe tip design parameters on compressor performance were evaluated by utilizing a computer simulation package and taking SRM-D asymmetric type rotor profile as an example. The result suggests that the requirements for high efficiency, large capacity, low inter-rotor contact force and low viscous friction loss do not always lead to the use of the same lobe tip designs. Of all the...