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Tytuł:
Analysis of the single stage cycloidal gearbox with lobe defects. Fault diagnosis attempts using coherence function and Morris minimum-bandwidth wavelets
Autorzy:
Król, Roman
Powiązania:
https://bibliotekanauki.pl/articles/27309893.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
cycloidal gearbox
frequency analysis
coherence
wavelets
multibody dynamics
przekładnia cykloidalna
analiza częstotliwości
dynamika wieloczłonowa
Opis:
In this article, the frequency characteristics of the forces and torques in the various cycloidal gearbox designs were investigated. The aim of the article is the search for frequency patterns that could be used in the formulation of a fault diagnosis methodology. Numerical analysis was performed in the cycloidal gearbox without defects as well as in cycloidal gearboxes with lobe defects or with removed lobes. The results of the numerical analysis were obtained in the multibody dynamics model of the cycloidal gearbox, implemented in Fortran and using the 2nd-order Runge-Kutta method for the integration of the motion equations. The used model is planar and uses Hunt and Crossley’s nonlinear contact modelling algorithm, which was modified using the Heaviside function and backlash to fit cycloidal gearbox model convergence demands. In the analysis of fault diagnosis methods, the coherence function and Morris minimum-bandwidth wavelets were used. It is difficult to find a unique pattern in the results to use in the fault diagnosis because of the random characteristics of the torques at the input and output shafts. Based on obtained results, a promising, low-vibration cycloidal gearbox design with removed 7 lobes of the single wheel was studied using the FFT algorithm.
Źródło:
Archive of Mechanical Engineering; 2023, LXX, 3; 409--431
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deep learning-based CNC milling tool wear stage estimation with multi-signal analysis
Autorzy:
Karabacak, Yunus Emre
Powiązania:
https://bibliotekanauki.pl/articles/27312777.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
wear stage estimation
milling
convolutional neural network
time-frequency analysis
Opis:
CNC milling machines are frequently used in the manufacturing of mechanical parts in the industry. One of the most important components of milling machines is the cutting tool. Monitoring the cutting tool wear is important for the reliability, continuity, and quality of production. Monitoring the tool and detecting the stage of wear are difficult processes. In this work, the convolutional neural network (CNN), which is a deep learning method in which the features are extracted by an inner process, was performed to detect the wear stages of the milling tool. These stages that define the total lifespan of the tool are known as initial wear (IW), steady-state wear (SSW), and accelerated wear (AW). Short Time Fourier Transform (STFT) was applied to signals, and signal spectrograms were used to train CNN models with different complex architectures. Vibration signals, acoustic emission signals, and motor current signals from The Nasa Ames Milling Dataset were used to obtain the spectrograms. Pre-trained CNNs (GoogleNet, AlexNet, ResNet-50, and EfficientNet-B0) detected the tool wear stage with varying accuracies. It has been seen that the time duration of model training increases as the size of the dataset grows and the network architecture becomes more complex. The recommended method has also been tested on the 2010 PHM Data Challenge Dataset. CNN shows promise for condition monitoring of milling operations and detecting tool wear stage.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 3; art. no. 168082
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Generative modelling of vibration signals in machine maintenance
Autorzy:
Puchalski, Andrzej Adam
Komorska, Iwona
Powiązania:
https://bibliotekanauki.pl/articles/28086927.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
time-frequency analysis
condition monitoring
anomalies detection
deep generative models
variational autoencoder
data distribution
Opis:
The exponential development of technologies for the acquisition, collection, and processing of data from real-world objects is creating new perspectives in the field of machine maintenance. The Industrial Internet of Things is the source of a huge collection of measurement data. The performance of classification or regression algorithms needs to take into account the random nature of the process being modelled and any incomplete observability, especially in terms of failure states. The article highlights the practical possibilities of using generative artificial intelligence and deep machine learning systems to create synthetic measurement observations in monitoring the vibrations of rotating machinery to improve unbalanced databases. Variational AutoencoderVAE generative models with latent variables in the form of high-level input features of time-frequency spectra were studied. The mapping and generation algorithm was optimised and its effectiveness was tested in the practical solution of the task of diagnosing the three operating states of a demonstration gearbox.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 4; art. no. 173488
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Methodology for the Composite Tire Numerical Simulation Based on the Frequency Response Analysis
Autorzy:
Karpenko, Mykola
Skačkauskas, Paulius
Prentkovskis, Olegas
Powiązania:
https://bibliotekanauki.pl/articles/24200834.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
tire
composite
finite elements metod
frequency analysis
numerical simulation
optimization
Opis:
Reliability and maintenance analysis in transport focus on the main objective of accident and incident investigations that benefit to better understanding of the causes of accidents and prevention of them in the future. The conducted research presents theoretical and experimental research on composite pneumatic tire used in transport engineering. The approach of the numerical simulation sequence which is offered in this research facilitates engineers in efficient determination of the dynamic properties and behaviour of vehicle tire at design stage. The tire materials have been tested by employing piezoelectric micro-vibration tests and frequency analyses. The Finite Element Method used for numerical simulation in combination with experimental measurements based on optimization by material frequency response, was applied in modelling tire material behaviour avoiding problems of composite structure modelling. The obtained results indicate that the offered methodology can be used in numerical simulation of composite tire investigation and considering material viscos-elastic properties.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 2; art. no. 163289
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Time-frequency Representation -enhanced Transfer Learning for Tool Condition Monitoring during milling of Inconel 718
Autorzy:
Zhou, Yuqing
Sun, Wei
Ye, Canyang
Peng, Bihui
Fang, Xu
Lin, Canyu
Wang, Gonghai
Kumar, Anil
Sun, Weifang
Powiązania:
https://bibliotekanauki.pl/articles/24200823.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
tool condition monitoring
time-frequency analysis
Markov Transition Field
transfer learning
Opis:
Accurate tool condition monitoring (TCM) is important for the development and upgrading of the manufacturing industry. Recently, machine-learning (ML) models have been widely used in the field of TCM with many favorable results. Nevertheless, in the actual industrial scenario, only a few samples are available for model training due to the cost of experiments, which significantly affects the performance of ML models. A time-series dimension expansion and transfer learning (TL) method is developed to boost the performance of TCM for small samples. First, a time-frequency Markov transition field (TFMTF) is proposed to encode the cutting force signal in the cutting process to two-dimensional images. Then, a modified TL network is established to learn and classify tool conditions under small samples. The performance of the proposed TFMTF-TL method is demonstrated by the benchmark PHM 2010 TCM dataset. The results show the proposed method effectively obtains superior classification accuracies for small samples and outperforms other four benchmark methods.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 2; art. no. 165926
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of modelling and simulation to evaluate the theta method used in diagnostics of automotive shock absorbers
Autorzy:
Lozia, Zbigniew
Powiązania:
https://bibliotekanauki.pl/articles/2124764.pdf
Data publikacji:
2022
Wydawca:
Sieć Badawcza Łukasiewicz. Przemysłowy Instytut Motoryzacji
Tematy:
frequency domain analysis
quarter car model
theta method
suspension damping
automotive diagnostics
Opis:
The dynamic properties of the car's suspension largely depend on the damping that results from the state of the shock absorbers. Their technical condition is essential for vehicle occupants’ comfort and traffic safety. It changes with the time and intensity of use of the vehicle. Therefore, adequate methods of non-destructive (diagnostic) testing of suspension damping have been sought for many years. The on-vehicle tests are particularly useful thanks to their low cost and short test duration time. The newest method is the ‘theta’ method which is the subject of the presented article. Notation ‘theta’ usually means relative damping (damping ratio) in the vibrating system. The paper asses four variants of the method. Two versions come from modal analysis and are also known as the ‘peak-picking method’ or ‘half-power method’. Two other versions are described in cited patent documentations. Three linear ‘quarter car' models with their description in the frequency domain were used to assess mentioned variants of the ‘theta’ method. Calculations were made for two typical datasets corresponding to the front and rear suspension system of a medium-class motor car. This provided grounds for general qualitative and (within a limited scope) quantitative assessment of the usefulness of individual variants of the method under analysis and for comparisons between them. The paper is to help in choosing the variant of the ‘theta’ method that would most likely find the application and that might be recommended to manufacturers and would-be purchasers of diagnostic suspension testers. The author has also highlighted the importance of possible further research.
Źródło:
Archiwum Motoryzacji; 2022, 96, 2; 5--30
1234-754X
2084-476X
Pojawia się w:
Archiwum Motoryzacji
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crack growth diagnostic of ball bearing using vibration analysis
Autorzy:
Belaidi, S.
Lecheb, S.
Chellil, A.
Mechakra, H.
Safi, B.
Kebir, H.
Powiązania:
https://bibliotekanauki.pl/articles/2174182.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
łożysko kulkowe
drgania
pękanie
zmęczenie
ball bearing
vibration analysis
frequency
cracking
diagnosis
fatigue life
Opis:
It is known that supported ball bearings have great effects on the vibrations of the gear transmission system, above in all the presence of local faults as well as the crack growths. For this purpose, this paper focuses on shock and vibration crack growth diagnostic of ball bearing using vibration analysis. Our work is devoted first to a study the static behaviour of the ball bearing by determining the stress, strain and displacement, then its dynamic behaviour by determining the first four natural frequencies. Secondly, a dynamic analysis study of the bearing was carried with defects as a function of crack size and location. The obtained results clearly show that the natural frequencies decrease in a non-linear way with the growth of the length of the crack, on the other hand the stress increases with the presence of the singular points of the crack. Finally, this residual decrease in natural frequencies can be used as an indicator of the state of failure, as well as a parameter used for the diagnosis and screening, and to highlight the fatigue life of the bearing.
Źródło:
International Journal of Applied Mechanics and Engineering; 2022, 27, 1; 35--45
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design and analysis of cementless hip-joint system using functionally graded material
Autorzy:
Asiri, Saeed
Powiązania:
https://bibliotekanauki.pl/articles/2065758.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
functionally graded material
cementless hip-joint system
natural frequency
harmonic response
fatigue analysis
finite element analysis
modal analysis
odpowiedź harmoniczna
analiza zmęczeniowa
analiza elementów skończonych
analiza modalna
Opis:
Functionally Graded Materials (FGM) are extensively employed for hip plant component material due to their certain properties in a specific design to achieve the requirements of the hip-joint system. Nevertheless, if there are similar properties, it doesn’t necessarily indicate that the knee plant is efficiently and effectively working. Therefore, it is important to develop an ideal design of functionally graded material femoral components that can be used for a long period. A new ideal design of femoral prosthesis can be introduced using functionally graded fiber polymer (FGFP) which will reduce the stress shielding and the corresponding stresses present over the interface. Herein, modal analysis of the complete hip plant part is carried out, which is the main factor and to date, very few research studies have been found on it. Moreover, this enhances the life of hip replacement, and the modal, harmonic, and fatigue analysis determines the pre-loading failure phenomena due to the vibrational response of the hip. This study deals with the cementless hip plant applying the finite element analysis (FEA) model in which geometry is studied, and the femoral bone model is based in a 3D scan.
Źródło:
Archive of Mechanical Engineering; 2022, LXIX, 1; 129--146
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
EMD-based time-frequency analysis methods of non-stationary audio signals
Autorzy:
Lewandowski, Marcin
Grodzicka, Salomea
Powiązania:
https://bibliotekanauki.pl/articles/2202413.pdf
Data publikacji:
2022
Wydawca:
Politechnika Poznańska. Instytut Mechaniki Stosowanej
Tematy:
empirical mode decomposition
non-stationary audio data
time-frequency analysis
empiryczna metoda dekompozycji
niestacjonarne dane dźwiękowe
analiza czasowo-częstotliwościowa
Opis:
To ensure that any time series data is appropriately interpreted, it should be analyzed with proper signal processing tools. The most common analysis methods are kernel-based transforms, which use base functions and their modifications to represent time series data. This work discusses an analysis of audio data and two of those transforms - the Fourier transform and the wavelet transform based on a priori assumptions about the signal's linearity and stationarity. In audio engineering, these assumptions are invalid because the statistical parameters of most audio signals change with time and cannot be treated as an output of the LTI system. That is why recent approaches involve decomposition of a signal into different modes in a data-dependent and adaptive way, which may provide advantages over kernel-based transforms. Examples of such methods include empirical mode decomposition (EMD), ensemble EMD (EEMD), variational mode decomposition (VMD), or singular spectrum analysis (SSA). Simulations were performed with speech signal for kernel-based and data-dependent decomposition methods, which revealed that evaluated decomposition methods are promising approaches to analyzing non-stationary audio data.
Źródło:
Vibrations in Physical Systems; 2022, 33, 2; art. no. 2022215
0860-6897
Pojawia się w:
Vibrations in Physical Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of sand p–y curves by predicting both monopile lateral response and OWT natural frequency
Autorzy:
Amel, Douifi
Djillali, Amar Bouzid
Subhamoy, Bhattacharya
Nasreddine, Amoura
Powiązania:
https://bibliotekanauki.pl/articles/2073761.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
FE analysis
p–y curve
Winkler model
cohesionless soil
monopile
offshore wind turbine
natural frequency
soil–monopile stiffness
Opis:
Extending the use of the p–y curves included in the regulation codes API and DNV to design large-diameter monopiles supporting offshore wind turbines (OWTs) was unsuccessful as it resulted in an inaccurate estimation of the monopile behavior. This had prompted many investigators to propose formulations to enhance the performances of Winkler model. In this paper, two case studies are considered. A case consisting of an OWT at Horns Rev (Denmark) supported by a monopile in a sandy soil was studied first. Taking the FEA using ABAQUS as reference, results of WILDOWER 1.0 (a Winkler computer code) using the recently proposed p–y curves giving design parameters were plotted and evaluated. In order to see the ability of proposed p–y curves to predict the monopile head movements, and consequently the first natural frequency (1st NF), a second case study consisting of a monopile supporting an OWT at North Hoyle (UK) was selected. The monopile head stiffness in terms of lateral, rocking, and cross-coupling stiffness coefficients, necessary for the 1st NF, were computed using both ABAQUS and WILDPOWER 1.0. Comparisons with the measured 1st NF showed that with the exception of one p–y model, none of other proposed Winkler methods is able to predict accurately this parameter.
Źródło:
Studia Geotechnica et Mechanica; 2022, 44, 1; 66--81
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Importance of seismic wave frequency in FEM-based dynamic stress and displacement calculations of the earth slope
Autorzy:
Fuławka, Krzysztof
Kwietniak, Anna
Lay, Vera
Jaśkiewicz-Proć, Izabela
Powiązania:
https://bibliotekanauki.pl/articles/2073762.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
slope stability
numerical analysis
seismic load
frequency analysis
Opis:
Reliable assessment of earthen dams' stability and tailing storage facilities widely used in the mining industry is challenging, particularly under seismic load conditions. In this paper, we propose to take into account the effect of the dominant frequency of seismic load on the stability assessment of tailing/earthen dams. The calculations are performed by finite element modelling (FEM) with the Mohr–Coulomb failure criteria. To separate the frequency content from other dynamic parameters describing the seismic wave, synthetic waveforms with identical amplitude and attenuation characteristics, but differing spectral characteristics have been used. The analysis has been performed for three different slope angles and two scenarios of seismic wave propagation. Consequently, the changes of total displacement and shear stresses depending on the frequencies have been determined and clearly show that lower frequencies cause higher stress levels and displacement. Finally, the response surface methodology has been applied to determine how different parameters affect the slope stability under dynamic load conditions. Overall, this study is a first step to improve the existing methods to assess slope stability when considering seismic load.
Źródło:
Studia Geotechnica et Mechanica; 2022, 44, 1; 82--96
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inter-harmonic parameter identification method based on transform with local maximum spectrum
Autorzy:
Sun, Lin
Song, Jing
Jin, Yan
Powiązania:
https://bibliotekanauki.pl/articles/2042793.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
inter-harmonic
parameter identification
power system
synchrosqueezed transform
time-frequency analysis
Opis:
In order to improve the detection accuracy of harmonics/inter-harmonics in power systems, a new method of harmonic/inter-harmonic detection based on synchrosqueezed transform and the Hilbert operator based on local spectrum maximum is proposed. Firstly, the spectrum of inter-harmonic signals is obtained through short-time Fourier transform, and the local maximum value of the spectrum in the frequency direction is detected. Then, based on the maximum frequency of the spectrum, a new frequency redistribution operator and synchronous extraction operator are constructed. It combines the operators with ridge detection for the decomposition of harmonic/inter-harmonic signals, so as to obtain a series of intrinsic mode function (IMF) components. Finally, the instantaneous amplitude and frequency of the IMF components is obtained by using the Hilbert operator. Meanwhile, according to the instantaneous frequency mutation point in the spectrum, the starting and ending time of transient harmonics/inter-harmonics is located accurately. Based on a low signal-to-noise ratio (SNR), the wavelet packet method (WP), Hilbert Marginal Spectrum method (HMS), synchrosqueezing wavelet transform method (SST), the Hybrid SST method (HSST), enhanced empirical wavelet transform (EEWT) and the proposed method are used to identify the harmonic/inter-harmonic parameters, respectively. The experimental results show that the proposed LMSST method can effectively separate the steady-state and transient harmonic/inter-harmonic signals, and has higher detection accuracy and better noise robustness.
Źródło:
Archives of Electrical Engineering; 2022, 71, 1; 189-209
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigations on an influence of the material properties on vibrations of active rocker-bogie suspension
Autorzy:
Sokół, Krzysztof
Pierzgalski, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/2173528.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
frequency analysis
suspension
rover
mobile platform
computational mechanics
analiza częstotliwości
zawieszenie
łazik
platforma mobilna
mechanika obliczeniowa
Opis:
Unmanned vehicles are often used in everyday life, mostly by rescue teams or scientists exploring new terrains. In those constructions, the suspension has constant dimensions, which leads to many disadvantages and limits the application area. The solution to these problems can be creating a six-wheeled mobile platform that can dynamically change the wheelbase in relation to the area of action or terrain inclination angle. The active change in location of the center of gravity gives a possibility to access sloppy obstacles not available with classical suspensions. The main scope of this study is to investigate the influence of material properties on vibration frequency at different lengths of suspension members. The obtained results will allow finding the optimum material for producing a prototype unit.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 1; e138239, 1--7
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monitoring of helicopter swash-plate wear using the FAM-C diagnosis method
Autorzy:
Gębura, Andrzej
Kowalczyk, Henryk
Tokarski, Tomasz
Handzel, Kacper
Klimaszewski, Sławomir Jerzy
Zgrzywa, Franciszek
Powiązania:
https://bibliotekanauki.pl/articles/2096175.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
frequency analysis
blade tip timing
bearing wear
gear wear
alternator
frequency modulation
power transmission
characteristic pattern
helicopter swash-plate
analiza częstotliwości
metoda wirującego obserwatora
zużycie łożyska tocznego
zużycie przekładni
modulacja częstotliwości
transmisja mocy
śmigłowiec
Opis:
Helicopter rotor dynamics (blade vibrations, ground resonance, influence of forward speed, etc.) play an important role in the wear and tear of the transmission system and power unit. Particularly fast wear of these components is to be expected in military helicopters in combat conditions, where the flight dynamics parameters are often exceeded. The FAM-C method developed at the Air Force Institute of Technology in Poland has been used to assess and monitor this wear. This method can be used to monitor damage to helicopter propulsion and transmission, where other "classical" methods are less effective due to a very complicated system of forces, variable as to the direction of amplitude and frequency, causing vibrations in closely spaced kinematic pairs. For this reason, vibroacoustic and thermal effects are created around these kinematic pairs, which interfere with each other. In a helicopter, the propulsion unit, including the power transmission unit, is at the same time the carrier unit. This has forced designers to construct a propulsion system with a much greater number of joints and bearing supports. This article presents the possibilities of the FAM-C method for monitoring of swash-plate main bearing wear. The swash-plates are not formally part of the helicopter's propulsion unit but are used to direct the thrust vector of the blades i.e., they direct the helicopter's power vector. Since during this process their components are observable by the FAM-C method, the authors found it necessary to include issues related to their diagnosis in this study. In the FAM-C method, the signal from the AC generator during the normal operation of the helicopter is processed. Analysis of this signal allows simultaneous monitoring of multiple engine and transmission components simultaneously. It does not require any separate sensors for this purpose - one "full-time" alternator or tachometer generator is - with proper collection and processing of the output voltage signal - the source of a whole range of diagnostic information. Thus, one generator is an observer of the technical condition of many elements of the power unit simultaneously. What's more, the signal can be collected from any place in the electrical network, which makes it possible to install the measuring system in safe locations, even while the power train is running. Some examples of diagnostic symptoms leading to wear detection are described. Research based on analysis of these findings with the use of the FAM-C method is described in the paper. In the FAM-C method, signal from the AC generator used in routine operation of the helicopter is processed. Signal analysis enables simultaneous monitoring of several engine and transmission elements. Some examples of diagnostic symptoms used to detect wear are described in the paper.
Źródło:
Diagnostyka; 2022, 23, 1; 1--12
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of the Change in the Tin Concentration in Bronzes to the Basic Components of the Sound of Bells
Autorzy:
Cekus, Dawid
Nadolski, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/2049724.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high-tin bronze
components of the sound of bell
frequency analysis
mechanical properties
velocity of sound
Opis:
The subject of the study was to determine the impact of changes in mechanical properties of high-tin bronzes on the basic components of the sound of a bell. Change in the tin concentration in the range of about 7.5 to 20 parts wt. in a casting alloy significantly affects the mechanical properties of the alloy such as Young’s modulus or hardness. The free vibrations of bells were obtained with the help of the finite element method. In the numerical analyses the mechanical properties of standard alloys were adopted. The obtained natural frequencies of the bell made of a bronze with different tin concentration in copper were compared with the acoustic properties of a real bell casted on the basis of the same ribs. A significant effect of the increase in the alloying share of tin on the obtained results was stated. In addition, the acoustic analysis of aluminum bronze C95500 have been performed. Based on the obtained results, authors stated that this material can replace the commonly used high tin bronze C91300 for the unit production of bells.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 2; 531-535
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
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