Wyniki wyszukiwania - Biblioteka Nauki

1

Influence of Damping on Transverse and Longitudinal Vibrations of T-type Frame

100%

Sochacki W. , Bold M.

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2017

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tom Vol. 41, No. 1

143--154

EN

In this paper, the problem of transverse and longitudinal damped vibration of T-type frame was formulated and solved. The vibration energy dissipation in the model occurs as a result of internal, constructional and external damping. Damping in adopted model is a result, of taken into account viscoelastic material of beams that modelled the system, motion resistance in frame supports and influence of medium surrounded the frame. Damped frequencies of vibrations and degree of amplitude decay were calculated. The study also presents eigenvalues of system vibration with respect to changes in damping coefficients and system geometry for selected rigidity of springs.

2

A semi-analytic approach to calculating the Strehl ratio for a circularly symmetric system.Part 2: dynamic wavefront

88%

Castaño-Fernandez A. B. , Martínez-Finkelshtein A. , Iskander D. R.

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tom Vol. 48, nr 2

211--223

EN

Close-form expression for the Strehl ratio calculated in the spatial frequency domain of the optical transfer function (SOTF) is considered for the case of time-varying dynamic optical system that has circular symmetry. Specifically, closed-form expressions for the temporally averaged SOTF are considered, which can be easily evaluated numerically (what we call a semi-analytic solution). As for the case of a static wavefront, described in Part 1 of this work, it is shown that the proposed methods are computationally more efficient than the commonly used approach based on the discrete Fourier transform.

3

Longitudinal vibrations of an elastically connected double-rod complex system. Part I, Free vibrations

63%

Oniszczuk Z.

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2006

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tom Vol. 22

291--296

4

Modelowanie i eksperymentalna identyfikacja parametrów hydraulicznego stabilizatora drgań wzdłużnych ładowarki łyżkowej

63%

Kosiara A.

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tom nr 2

207-212

PL

W pracy przedstawiono zagadnienia związane z modelowaniem pasywnych hydraulicznych stabilizatorów kątowych drgań wzdłużnych kołowych czołowych ładowarek łyżkowych. W szczególności przeanalizowano wpływ na wyniki obliczeń linearyzacji modelu stabilizatora. W pracy omówiono także eksperymentalną identyfikację wybranych parametrów modelu układu stabilizacji drgań.

EN

In article there are explain some problems connected with modelling of passive hydraulic longitudinal oscillation stabilizers in front wheeled loaders. Particularly, the influence on results of linearization of stabilizer's model was analyzed. Experimental identification of selected parameters of the model was also discussed.

5

Mechanical systems vibrating longitudinally with the transportation effect

51%

Buchacz A. , Żółkiewski S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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tom Vol. 21, nr 1

63-66

EN

Purpose: High work speeds of mechanisms, using materials with high flexibility, high precision of work, etc. are the cause of searching of the new ways of modelling. One of these ways is presented in this thesis. The main purpose of this thesis is the dynamical analysis with taking into consideration the interaction between main motion and local vibrations during the model is loaded by longitudinal forces. Design/methodology/approach: Derived equations of motion were made by classical methods, with generalized coordinates and generalized velocities assumed as orthogonal projections of individual coordinates and velocities of the rod and manipulators to axes of the global inertial frame. Findings: Mathematical model of the longitudinally vibrating systems in terms of plane motion can be put to use to derivation of the dynamical flexibility of these systems, and also those equations are the starting point to the analysis of complex systems, especially we can use those equations to derivation of the substitute dynamical flexibility of n-linked systems in transportation. Research limitations/implications: In the thesis were considered mechanical systems vibrating longitudinally in terms of rotation. Next problem of dynamical analysis is the analysis of systems in non-planar transportation and systems loaded by transversal forces. Practical implications: Results of this thesis can be put to use into machines and mechanisms in transportation such as: wind power plant, high speed turbines, rotors, manipulators and in aerodynamics issues, etc. Originality/value: Up to now there were analyzed beams and rods in a separate way, first main motion of the system and after that the local vibrations. The new approach of modelling were presented by authors of this thesis, a new modelling took into consideration the interaction between those two displacements. There was defined the transportation effect for models vibrating longitudinally in this thesis.

6

Wykorzystanie parametrów drgań wzdłużnych tulei cylindrowych w diagnostyce okrętowych tłokowych silników spalinowych

51%

Witkowski K.

Diagnostyka

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2005

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tom Vol. 35

137--144

PL

W artykule przedstawiono wyniki badań wstępnych dotyczących możliwości wykorzystania w diagnostyce okrętowych silników tłokowych drgań wzdłużnych tulei cylindrowej. Wyniki badań wykazały, że ten sygnał wibroakustyczny może być przydatny do wykrywania stanów przedzatarciowych układu tłok-cylinder.

EN

In the paper the preliminary research results at the possibilities at using cylinder liner longitudinal vibrations in marine diesel engine diagnostics has been presented. The research results have proven that these vibroacoustics signal can be useful to defect the prefrictional states of piston-cylinder liner system.