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Measurement and analysis of tram wheel vibration at riding on track
Pešek, Luděk ; Vaněk, František ; Cibulka, Jan ; Vaněk, P. ; Boháč, T.
In the contribution the design, realization and results of vibro-acoustic measurements on the riding tram wheel is presented. The operational tests were performed on the tram KT8D5 of DPMB Brno. The tram wheel with a special rubber padding design was equiped with add-on vibro-acoustic dampers. Efficiency of the add-on dampers was evaluated from comparison tests on the tram wheel with and without these dampers. Third octave and time-frequency analysis of the measured vibro signals is herein presented for a bow track passage. For analysis of operational vibration modes the FE model of the wheel with add-on dampers was developed and applied.
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Evaluation of vibrational eigenfrequencies and eigenmodes and loss factor for monoblock rail wheel
Pešek, Luděk ; Veselý, Jan
The aim of this research was evaluated experimentally eigenfrequencies, eigenmodes and loss factors for the monoblock rail wheel in two options: a) without acoustic damping disc, b) with acoustic damping disk. Excitation was realized by an electrodynamic vibrator with different levels of excitation and by hammer. The raill wheel was forced on a wheel set placed on a special frame. Frequency range of modal analysis was up to 6400Hz with step 0.25Hz. The measurement and analysis was performed for all identifiable eigenfrequencies with emphasis on eigenmodes having from two up seven node radials without node cirles. Pro determination of eigenfrequencies and loss factors corresponding eigenmodes the modal analysis was carried out for all options of the damping disk.
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Design, development and realization of vibration measurement on riding metro wheel with and without add-on damper
Pešek, Luděk ; Vaněk, František ; Vaněk, Petr ; Cibulka, Jan
The aim of this research was design, developement and realization of vibration measurement (acceleration) of the riding metro wheel with and without add-on damper. The radiotelemetric method with four measurement channels was used for the operational measurement of vibration and noise. The solution was devided into four steps a) design and devolopement, laboratory tests and production of modified radiotelemtric equipment for measurement on the tram wheel; b) installation of the sensors and radiotelemetric equipment; c) realization of vibration operational measurement; d) measured data processing. In the report there is described a methodology of measurement and dynamic analysis used for comparision of the wheel with and withoud add-on dampers. The different riding regimes and tracks, i.e. direct, bow , were analysed. The third octave spectra nd amplitude time-frequency characteristics of accelerations and acoustic pressure were evaluated from the digital recorded time signals.
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Design, development and realization of vibration measurement on riding tram wheel with and without add-on damper
Pešek, Luděk ; Veselý, Jan ; Vaněk, František ; Cibulka, Jan ; Bula, Vítězslav
The aim of this research was design, developement and realization of vibration measurement (acceleration) of the riding wheel with and without add-on damper. The solution was devided into four steps a) design and devolopement, laboratory tests and production of modified radiotelemtric equipment for measurement on the tram wheel; b) installation of the sensors and radiotelemetric equipment; c) realization of vibration measurement of the carriage KT8D5; d) measured data processing. In the report there is described a methodology of measurement and dynamic analysis used for comparision of composed rim-rubber-disk wheel with and withoud add-on dampers. The different riding regimes and tracks, i.e. direct, bow and cross, were analysed.
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Vibration cylindrical shells containing flowing fluid
Zolotarev, Igor
The natural frequencies of the free vibration of a circular cylindrical shell containing flowing inviscid fluid are studied. The numerical results obtained by use ANSYS numerical package are analyzed for frequency-modal properties of two different numerical models and compared with results of the analytical calculations. Application different FEM models that are created with using fluid-structure-interaction elements (FSI) and without it are analyzed too.
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Dynamic analysis of turbine blade M4
Hendrych, Pavel ; Pešek, Luděk ; Vaněk, František
This contribution is aimed at the numerical dynamic analysis of steam turbine low-pressure blade M4 both in steady state and under rotation. The verification of the free-free numerical model based on the modal analysis was carried out. The numerical model was developed as a three-dimensional finite element model. The Cambell diagram was calculated with respect to stress stiffening and spin softening effects.
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