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Miroslav Byrtus

Bio: Miroslav Byrtus is an academic researcher from University of West Bohemia. The author has contributed to research in topics: Vibration & Rotor (electric). The author has an hindex of 7, co-authored 51 publications receiving 203 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, the authors present an original method of the mathematical modeling of gear drive nonlinear vibrations using modal synthesis method with degrees of freedom number reduction, which is used for investigation of two-stage gearbox nonlinear vibration.

54 citations

Journal ArticleDOI
TL;DR: In this article, the effects of radial bearing clearances on the dynamical response of the turbocharger rotor are analyzed by means of flexible multibody dynamics approaches, which is solved numerically.

38 citations

Journal ArticleDOI
TL;DR: In this paper, a friction element placed in the shroud between the blade heads is used as a source of passive damping in various mechanical systems, and the effect of friction is studied for the case of harmonic excitation by suitable frequency and subsequent free vibration attenuation.
Abstract: Friction forces can be advantageously used as a source of passive damping in various mechanical systems. This paper deals with an experimental modelling and numerical simulation of blades interaction by means of a friction element placed in the shroud between the blade heads. The radial force, which represents the centrifugal force acting on the friction element, determines the values of contact forces between the element and blades. The experimental set-up for a couple of non-rotating blades is described in the paper, and the measured dynamic response of two blades is documented. The same situation is modelled by means of a basic and a more complex dynamical model of two blades with a friction element. The effect of friction is studied for the case of harmonic excitation by suitable frequency and subsequent free vibration attenuation. Both mathematical models are based on the finite element method combined with lumped rigid bodies. The interaction of the friction element and blades is described by normal contact and tangential friction forces derived for particular geometrical parameters of the studied mechanical system. The performed comparison of experimental and numerical results shows the satisfactory agreement and the modelling methodology could be used for possible parameter optimization.

27 citations

Journal ArticleDOI
TL;DR: In this article, the authors presented linearized coefficients for finite-length journal bearings based on the HD forces with multiplicative correction polynomials applied to the infinitely short and the infinitely long solutions under the assumption of π-film boundary condition.

22 citations

Proceedings ArticleDOI
01 Dec 2014
TL;DR: In this paper, the air gap field distribution of an induction machine operating under special conditions is discussed, focusing mainly on effects of machine's load and its rotor eccentricity on volume of space harmonics and their magnitudes.
Abstract: The paper discusses the air gap field distribution of an induction machine operating under special conditions. It focuses mainly on effects of machine's load and its rotor eccentricity on volume of space harmonics and their magnitudes. The study compares limited analytical prediction with full-scale FEA approach and gives a short overview of crucial aspects of machines' design.

20 citations


Cited by
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Journal ArticleDOI
TL;DR: Basic and clinical aspects of eight antimuscarinic agents clinically used to treat urinary dysfunction in patients with OAB are highlighted and the measurement of drug‐receptor binding after oral administration of these agents allows for clearer understanding of bladder selectivity by the integration of pharmacodynamics and pharmacokinetics under in vivo conditions.

63 citations

Journal ArticleDOI
TL;DR: In this paper, the static and dynamic lubrication parameters of the floating ring bearing (FRB) were investigated considering the effects of various coupling factors such as clearance ratio, vertical load and rotating speed.

62 citations

Journal ArticleDOI
TL;DR: In this article, the stochastic behavior of hydrodynamic journal bearings is investigated by solving the Reynolds equation with random parameters numerically based on finite difference method, and the steady state and dynamic characteristics are quantified considering random variabilities in eccentricity and surface roughness.

56 citations

Journal ArticleDOI
TL;DR: In this article, the authors present an original method of the mathematical modeling of gear drive nonlinear vibrations using modal synthesis method with degrees of freedom number reduction, which is used for investigation of two-stage gearbox nonlinear vibration.

54 citations

01 Jan 2002
TL;DR: A method will be presented to optimize two different types of underplatform dampers in bladed disk applications with respect to a maximum damping effect in order to investigate nearly arbitrary contact geometries and spatial blade vibrations.
Abstract: One of the main tasks in the design of turbomachines like turbines, compressors, and fans is to increase the reliability and efficiency of the arrangement Failures due to blade cracks are still a problem and have to be minimized with respect to costs and safety aspects To reduce the maximum stresses, the blades can be coupled via friction damping devices such as underplatform dampers that are pressed onto the blade platforms by centrifugal forces In this work, a method will be presented to optimize two different types of underplatform dampers in bladed disk applications with respect to a maximum damping effect In practice, underplatform dampers with various geometric properties—cylindrical and wedge-shaped—are commonly used and lead to different contact conditions A discretization of the contact areas between the blade platforms and the dampers is applied to be able to investigate nearly arbitrary contact geometries and spatial blade vibrations The functionality of the two mentioned damper types has been studied in detail under different working conditions of the assembly The advantages and disadvantages of both damper types are pointed out and strategies are presented to improve the damper design In this context, the influence of mistuning effects is discussed in terms of statistical mistuning of the blades’ natural frequencies due to manufacturing tolerances as well as systematical mistuning due to a deliberate slight variation of the blade masses or geometries

54 citations