Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Haddar, M." wg kryterium: Autor


Tytuł:
Mode of failure for reinforced concrete beams with GFRP bars
Autorzy:
Masmoudi, A.
Ouezdou, M. B.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/279428.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
crack propagation
flexural failure
concrete
GFRP bars
stress distribution
Opis:
Crack propagation in concrete structures is a very complicated process. An experimental method to predict the stress distribution of a cracked GFRP reinforced concrete flexural beam is presented. The beam subjected to four-point bending is internally reinforced with unidirectional GFRP bars. The aim of this investigation is to study the flexural performance of reinforced concrete members strengthened using GFRP bars. For the flexural tests performed on reinforced concrete beams strengthened with GFRP bars, the ultimate load of the beams strengthened with GFRP was reasonably increased. The mode of failure for beams reinforced with GFRP sections is slightly different compared with the traditional beam. The GFRP reinforced concrete beams fail either by concrete crushing at the compression zone or rupture of the GFRP reinforcement.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 4; 1137-1146
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability analysis and dynamic behaviour of a flexible asymmetric rotor supported by active magnetic bearings
Autorzy:
Attia Hili, M.
Bouaziz, S.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280401.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
asymmetric rotor
finite element
Floquet’s theory
dynamic coefficients
stability
Opis:
The objective of this work is to show the influence of dynamic characteristics of Active Magnetic Bearings (AMBs) on the stability and dynamic response of an asymmetric and unbalanced rotor. Indeed, AMBs have been successfully applied in several industrial machinery facilities. Their main advantages are the contactless working principle, frictionless suspension and operation in very high speeds. Firstly, the AMBs dynamic support parameters have been obtained through electromagnetic theory. Then, a generalized system equations of motion have been derived using the finite element method. The motion of a rotor the shaft cross-section of which is asymmetric is generally governed by ordinary differential equations with periodic coefficients. Floquet’s theory is used to investigate the stability of this system of equations. Finally, numerical simulation results are presented and discussed.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 3; 751-763
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of geometry and impedance variation on the acoustic performance of a porous material lined duct
Autorzy:
Masmoudi, A.
Makni, A.
Taktak, M.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/281635.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
cylindrical duct
discontinuity effect
transmission
reflection
acoustic attenuation
Opis:
In this paper, the effect of geometry and impedance on the acoustic behavior of wall and lined cylindrical ducts is investigated using a numerical model which enables one to compute the reflection and the transmission coefficients of such ducts using the multimodal scattering matrix. From this matrix, the acoustic power attenuation is deduced. By using these tools, the effect of duct diameter increase and duct diameter decrease of the wall or lined duct section is studied. The numerical results are obtained for two configurations of wall and lined ducts. Numerical coefficients of transmission and reflection as well as the acoustic power attenuation show the relative influence of each type of variation.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 2; 679-694
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical characterization of an axisymmetric lined duct with flow using the multimodal scattering matrix
Numeryczna charakteryzacja wyściełanego przewodu osiowo-symetrycznego z przepływem za pomocą wielomodalnej macierzy rozpraszania
Autorzy:
Taktak, M.
Majdoub, M. A.
Haddar, M.
Bentahar, M.
Powiązania:
https://bibliotekanauki.pl/articles/281218.pdf
Data publikacji:
2013
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
lined duct
scattering matrix
mean flow
Opis:
In this paper, the development of a numerical method to compute the multimodal scattering matrix of a lined duct in the presence of flow is presented. This method is based on the use of the convected Helmholtz equation and the addition of modal pressures at duct boundaries as additional degrees of freedom of the system. The boundary effects at the inlet and outlet of the finite waveguide are neglected. The choice of this matrix is justified by the fact that it represents an intrinsic characterization of a duct system. The validation of the proposed finite element is done by a comparison with the analytical formulation for simple cases of ducts. Then, the numerical coefficients of the scattering matrix of a lined duct and its acoustic power attenuation are computed for several flow velocities to evaluate the flow effect.
W pracy zaprezentowano numeryczną metodę wyznaczania macierzy rozpraszania dla wyściełanego przewodu z uwzględnieniem wewnętrznego przepływu czynnika. Metodę oparto na zastosowaniu równania konwekcji Helmholtza z wprowadzeniem ciśnień modalnych na brzegach jako dodatkowych stopni swobody układu. Efekty brzegowe na wlocie i wylocie przewodu falowego o skończonej długości pominięto. Wybór macierzy rozpraszania uzasadniono faktem, że reprezentuje ona wewnętrzną charakterystykę analizowanego modelu. Zaproponowany element skończony zweryfikowano poprzez porównanie z istniejącymi rozwiązaniami analitycznymi dla prostych przypadków konfiguracji przewodu. Następnie numerycznie obliczono wartości elementów macierzy rozpraszania oraz współczynniki tłumienia akustycznego dla kilku prędkości przepływu w celu określenia, jak dalece wpływa on na badany układ.
Źródło:
Journal of Theoretical and Applied Mechanics; 2013, 51, 2; 313-325
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical Modelling of the Acoustic Pressure Inside an Axisymmetric Lined Flow Duct
Autorzy:
Taktak, M.
Majdoub, M. A.
Bentahar, M.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/177750.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
lined duct
mean flow
finite element method
axisymmetric duct
Opis:
Numerical methods are mostly used to predict the acoustic pressure inside duct systems. In this paper, the development of a numerical method based on the convected Helmholtz equation to compute the acoustic pressure inside an axisymmetric duct is presented. A validation of the proposed method was done by a comparison with the analytical formulation for simple cases of hard wall and lined ducts. The effect of the flow on the acoustic pressure inside these ducts was then evaluated by computing this field with different Mach numbers.
Źródło:
Archives of Acoustics; 2012, 37, 2; 151-160
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Guided wave propagation in thermal media through the semi analytical finite element method
Autorzy:
Bouchoucha, F.
Chaabane, S.
Ichchou, M. N.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/281275.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
semi analytical finite element
thermal media
dispersion
velocity
Opis:
In this paper, the issue of the estimation of wave propagation characteristics in thermal media is dealt with. A formulation, named the Thermal Semi Analytical Finite Element, based on the semi analytical finite element approach coupled with the thermal effect is offered. Temperature variations affect the mechanical properties of the waveguide. The question of dispersion curves and group velocities is studied. This study is expected to be of use in the sensitivity analysis of guided waves for wave propagation in thermal environment. Comparisons between numerical and analytical results are given to show the effectiveness of the proposed approach.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 1; 285-293
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vibration analysis of three-layered nanobeams based on nonlocal elasticity theory
Autorzy:
Kammoun, N.
Jrad, H.
Bouaziz, S.
Soula, M.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280463.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
beams theories
nonlocal elasticity theory
vibration analysis
GDQ method
Opis:
In this paper, the first investigation on free vibration analysis of three-layered nanobeams with the shear effect incorporated in the mid-layer based on the nonlocal theory and both Euler Bernoulli and Timoshenko beams theories is presented. Hamilton’s formulation is applied to derive governing equations and edge conditions. In order to solve differential equations of motions and to determine natural frequencies of the proposed three-layered nanobeams with different boundary conditions, the generalized differential quadrature (GDQM) is used. The effect of the nanoscale parameter on the natural frequencies and deflection modes shapes of the three layered-nanobeams is discussed. It appears that the nonlocal effect is important for the natural frequencies of the nanobeams. The results can be pertinent to the design and application of MEMS and NEMS.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 4; 1299-1312
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of viscoelastic and porous materials on sound transmission of multilayer systems
Autorzy:
Felhi, H.
Trabelsi, H.
Taktak, M.
Chaabane, M.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280164.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
porous material
multilayer system
transmission loss
transfer matrix
Opis:
Multilayer structures allow obtaining good performance in acoustic insulation to eliminate unwanted noise in the medium and high frequencies in many applications such as building and transport industry. In this paper, the sound transmission of multilayer systems is studied using the Transfer Matrix Method (TMM). The studied multi-layered panels include elastic, viscoelastic and porous materials. Several configurations of multilayer systems are studied, and their corresponding transmission loss T L is computed. Also, the effects of porous material characteristics are studied to evaluate the impact of each parameter.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 4; 961-976
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of the gear local damage and profile error of the gear on the drivetrain dynamic response
Autorzy:
Ghorbel, A.
Zghal, B.
Abdennadher, M.
Walha, L.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280233.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
dynamic behaviour
clutch
gear
brake disc
gear local damage
gear profile error
Opis:
The dynamic modeling of vibration of a drivetrain is used for increasing our information about vibration generating mechanisms, especially in the presence of some kind of gear faults. This paper describes a research work on the automotive driveline modeling, vibration analysis, and the effect of gear defects on the dynamic behavior of the system. Firstly, main drivetrain components including the engine, clutch, single stage spur gearbox and disc brake are modeled, respectively. The nonlinear dynamic model is simulated by a thirteen degrees of freedom (DOF) system and the nonlinear function is due to the dry friction path. Secondly, two types of defects are modeled and introduced into the spur gear system; local damage and profile error. Then, the nonlinear equations of motion are solved by the numerical Runge Kutta method and a comparative study of the dynamic behavior of the system in healthy and defected cases is discussed for each fault type. The influence of the defects on the vibration response is presented in the time and frequency domain. Finally, analysis of the two defects together is presented.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 3; 765-779
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modal analysis of gearbox transmission system in bucket wheel excavator
Autorzy:
Karray, M.
Feki, N.
Khabou, M. T.
Chaari, F.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280984.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
spiral bevel gear
helical planetary gear
bucket wheel excavator
modal properties
Opis:
Planetary gears are widely used in modern machines as ones of the most effective forms of power transmission. In this paper, a special configuration of a gearbox composed of one stage spiral bevel gear and a two stage helical planetary gear used in a bucket wheel excavator gearbox is presented to investigate its modal properties. A lumped-parameter model is formulated to obtain equations of motion and the eigenvalue problem is solved. The modes are presented in low-frequency and high-frequency bands. Distributions of modal kinetic and strain energies are studied.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 1; 253-264
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inverse method for a one-stage spur gear diagnosis
Autorzy:
Akrout, A.
Tounsi, D.
Taktak, M.
Abbes, M. S.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/949292.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Independent Component Analysis (ICA)
source identification
gear mechanism
geometrical defects
Opis:
In this paper, a source separation approach based on the Blind Source Separation (BSS) is presented. In fact, the Independent Component Analysis (ICA), which is the main technique of BSS, consists in extracting different source signals from several observed mixtures. This inverse method is very useful in many fields such as telecommunication, signal processing and biomedicine. It is also very attractive for diagnosis of mechanical systems such as rotating machines. Generally, dynamic responses of a given mechanical system (displacements, accelerations and speeds) measured through sensors are used as inputs for the identification of internal defaults. In this study, the ICA concept is applied to the diagnosis of a one-stage gear mechanism in which two types of defects (the eccentricity error and the localized tooth defect)are introduced. The finite element method allows determination of the signals corresponding to the acceleration in some locations of the system, and those signals may be used also in the ICA algorithm. Hence, the vibratory signatures of each defect can be identified by the ICA concept. Thus, a good agreement is obtained by comparing the expected default signatures to those achieved by the developed inverse method.
Źródło:
Journal of Theoretical and Applied Mechanics; 2015, 53, 3; 617-628
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic behavior of a rotor supported by angular ball bearings
Autorzy:
Abbes, M. S.
Hentati, T.
Maatar, M.
Fakhfakh, T.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/327818.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
łożysko kulkowe skośne
wirnik
analiza dynamiczna
angular ball bearing
rotor
dynamic analysis
bearing interaction
Opis:
The wide range and large scale usage of rolling bearings indicates their necessity and vital contribution to the performance of modern industries. In this paper, a non linear model, predicting mechanical behavior of the loaded angular ball bearing, have been developed. The dynamic behavior of a rotor supported by two angular ball bearings is analyzed. The finite element method is used and the rotor is decritizied on beam elements. A mathematical modal taking account different sources of non linearity: the Hertzian contact force and the action of all balls on the bearings inner races, is developed. The Newmark algorithm coupled with Newton Raphson iterative method is used to solve the non linear differential equation iteratively.
Źródło:
Diagnostyka; 2009, 3(51); 3-8
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vibro-acoustic analysis of laminated double glazing using the force identification method
Autorzy:
Ben Jdidia, M
Akrout, A
Tounsi, D
Fakhfakh, T.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/949211.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
fluid-structure interaction
thin-film laminated plate
ICA
excitation force
Kurtosis
Opis:
This paper presents a procedure for identifying wave forms and excitation frequencies of some forces applied on a given complex fluid-structure coupled system by using only its vibro-acoustic response. The considered concept is called the Independent Component Analysis (ICA) which is based on the Blind Source Separation (BSS). In this work, the ICA method is exploited in order to determine the excitation force applied to a thin-film laminated double glazing system enclosing a thin fluid cavity and limited by an elastic joint. The dynamic response of the studied fluid-structure coupled system is determined by finite element discretization and minimization of the homogenized energy functional of the coupled problem. This response will serve as the input for the ICA algorithm in order to extract the applied excitation.
Źródło:
Journal of Theoretical and Applied Mechanics; 2014, 52, 4; 895-904
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic response of a spur gear system with uncertain parameters
Autorzy:
Guerine, A.
Hami, A. E.
Walha, L.
Fakhfakh, T.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/280323.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
uncertainty
spur gear system
polynomial chaos approach
gear parameters
Opis:
In this paper, we propose a new approach for taking into account uncertainties based on the projection on polynomial chaos. The new approach is used to determine the dynamic response of a spur gear system with uncertainty associated to gear system parameters. The simulation results are obtained by the polynomial chaos approach for dynamic analysis under uncertainty. The proposed approach is an efficient probabilistic tool for uncertainty propagation. It has been found to be an interesting alternative to the parametric studies. The polynomial chaos results are compared with Monte Carlo simulations.
Źródło:
Journal of Theoretical and Applied Mechanics; 2016, 54, 3; 1039-1049
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Porous material effect on gearbox vibration and acoustic behavior
Autorzy:
Letaief, M. R.
Walha, L.
Taktak, M.
Chaari, F.
Haddar, M.
Powiązania:
https://bibliotekanauki.pl/articles/281269.pdf
Data publikacji:
2017
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
porous material
gearbox
vibro-acoustic behavior
Opis:
In this paper, we define a resolution method to study the effect of a porous material on vibro-acoustic behavior of a geared transmission. A porous plate is coupled with the gearbox housing cover. The developed model depends on the gearbox characteristic and poroelastic parameters of the porous material. To study the acoustic effect of the housing cover, the acoustic transmission loss is computed by simulating numerically the elastic-porous coupled plate model, and the numerical implementation is performed by directly programming the mixed displacement-pressure formulation. To study the vibration effect, the bearing displacement is computed using a two-stage gear system dynamical model and used as the gearbox cover excitation. Numerical implementation is performed by direct programming of the Leclaire formulation.
Źródło:
Journal of Theoretical and Applied Mechanics; 2017, 55, 4; 1381-1395
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies