Národní úložiště šedé literatury Nalezeno 19 záznamů.  1 - 10další  přejít na záznam: Hledání trvalo 0.00 vteřin. 
Applications of blade vibration measurements in the laboratory of rotational laser vibrometry
Maturkanič, Dušan ; Procházka, Pavel ; Hodboď, Robert ; Mekhalfia, Mohammed Lamine ; Voronova, Evgeniya
The Laboratory of Rotational Laser Vibrometry was established at the Institute of Thermomechanics AS CR, v.v.i. in 2015 and the first experiments were started the following year. The measurements are intended for the research of vibration of rotating blades. The paper includes a summary of measurement results using a special turbine model and their consequences in theoretical research, as well as measurements with a real compressor of aircraft engine and comparison with computational analysis. The paper also describes the complex system for measurement and analysis.
Identification of the blade tip possition and measurement techniques using the BTT method
Maturkanič, Dušan ; Procházka, Pavel ; Hodboď, Robert ; Mekhalfia, Mohammed Lamine
This paper describes the existing practice in identifying and defining the position of the blade tips and the relevant technique for measuring their vibration during rotation. In connection with the effort to precisely define the position of the vibrating blade, the paper also analysed the possibilities of unambiguous determination of its position. This work creates a parallel branch to signal processing in the complex system of precision measurement and analysis of blade vibration, which was mentioned in previous papers.
Analytické postupy řešení kmitání lopatek pro použití u metody Blade Tip Timing - teoretický popis metody
Maturkanič, Dušan ; Procházka, Pavel ; Mekhalfia, Mohammed Lamine
Práce je zaměřena na analytický přístup k řešení problematiky kmitání lopatek turbíny a kompresoru metodou Blade Tip Timing. Ve zprávě je navržena nová metoda, pro niž byly stanoveny podmínky řešení. Ověření metody bylo provedeno prostřednictvím simulace, kdy byla vyhodnocena spolehlivost, u které byla zadávána správná vstupní data a výpočet probíhal po dostatečně dlouhou dobu, zatímco na základě záměrně zkreslených vstupních dat byla ověřována její přesnost. Součástí zprávy je také vazba výsledků výpočtu frekvence kolísajících otáček, získaných deterministickou metodou, která byla popsána v předchozích pracích, a s nimiž lze dosáhnout přesnějšího výpočtu frekvence a amplitudy kmitání lopatek v reálných podmínkách.\n\n
Vibration mode shape extraction of bladed disk
Mekhalfia, Mohammed Lamine ; Procházka, Pavel ; Tchawou Tchuisseu, Eder Batista ; Maturkanič, Dušan ; Hodboď, Robert
This research paper deals with the experimental protocol followed to visualize the vibration mode shape of an aero-engine bladed disk. This study is based on a comparison between the numerical results obtained through Finite element methods (FEM) using ANSYS software and experimentally using the laser Doppler vibrometer. Therefore the bladed disk was transformed into a 3D virtual environment and structural analysis was performed. The results demonstrate a match between the numerical and the experimental one, this match offers the possibility for using the model for future studies.
Two-way fluid structure interaction study of aero-engine compressor blade vibration under air excitation
Mekhalfia, Mohammed Lamine ; Procházka, Pavel ; Tchawou Tchuisseu, Eder Batista ; Maturkanič, Dušan ; Hodboď, Robert
In this paper, we provide a numerical method via FEM software (ANSYS) using two-way Fluid-Structure Interaction (FSI) solver to estimate the blade’s vibration where the force used to excitation is a continuous air jet. This will help to provide data to diagnostic blade condition and health monitoring and a bridge toward a precise study of the blade’s dynamic under rotation and the estimation of blade’s displacement to define the amplitude and the frequency that occurs under different types of excitation which is a pillar for the process of machine condition and health monitoring.
Numerical estimation of blade displacement due to air excitation
Mekhalfia, Mohammed Lamine ; Procházka, Pavel ; Tchawou Tchuisseu, Eder Batista ; Hodboď, Robert ; Maturkanič, Dušan
For the last few years, vibration measurement has taken an intense interest from research activities. For this reason, this article considers, besides vibration measurements, the impact of air forced excitation on blade motion, displacement and vibration through both simulation analysis and The Transformation of mathematical analysis that explain the interaction between fluid (Air) and the structure (Blade) into numerical setup along with FEM analysis through ANSYS Software. 3D Blade was created to meet the same characteristics of the real blade to enable real environment criteria for the simulation.
Dynamics of a magnetically excited blade: theoretical and experimental analysis
Tchawou Tchuisseu, Eder Batista ; Procházka, Pavel ; Mekhalfia, Mohammed Lamine ; Hodboď, Robert ; Maturkanič, Dušan
This work dealt with the theoretical and experimental analysis of a static blade subjected to a magnetic excitation. The theoretical analysis combines the modeling and design of the blade via ANSYS in whih the modal analysis is done. Both methods showed qualitative agreement of the results.
Accuracy of the analytical methods developed for blade tip-timing analysis
Maturkanič, Dušan ; Procházka, Pavel ; Kozánek, Jan
Within the research of methods for precision solution of rotor blade vibration based on the philosophy of Blade Tip-Timing at the Institute of Thermomechanics AS CR, v.v.i., the effort was concentrated on the decomposition of measured data. This paper describes the accuracy of analytical methods taking into consideration the errors of the measured sensors or the influence of the measurement conditions on the results.
Dependence of signal strangth on the radial distance and different types of magnets
Procházka, Pavel ; Voronova, Evgeniya ; Maturkanič, Dušan
The paper describes dependence of signal strength on the radial distance between the sensor and the measured object and dependence of signal strength on the different types of magnets. The measurements were performed in the laboratory of the rotational laser vibrometry originated at the Institute of Thermomechanics AS CR, v.v.i.
A simple algorithm for probes positioning in BTT systems
Tchawou Tchuisseu, Eder Batista ; Procházka, Pavel ; Maturkanič, Dušan
The Blade Tip Timing (BTT), a non-contact method for measuring the blade tip displacement through the time of arrival, is studied in this article. This work proposes a simple algorithm based on the minimization of the coherence and the condition number of the sensingmatrix for defining the best probe positioning in the case of synchronous and asynchronous vibrations.

Národní úložiště šedé literatury : Nalezeno 19 záznamů.   1 - 10další  přejít na záznam:
Chcete být upozorněni, pokud se objeví nové záznamy odpovídající tomuto dotazu?
Přihlásit se k odběru RSS.