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The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Fri, 09 Aug 2024 00:05:27 GMT2024-08-09T00:05:27ZBleustein-Gulyaev waves in a finite piezoelectric material loaded with a viscoelastic fluid
http://hdl.handle.net/10985/23164
Bleustein-Gulyaev waves in a finite piezoelectric material loaded with a viscoelastic fluid
EL BAROUDI, Adil; LE POMMELLEC, Jean Yves
A generalized analytical approach for the propagation of Bleustein–Gulyaev wave in a piezoelectric material loaded on its surface with a viscoelastic fluid is established in this paper. The Bleustein–Gulyaev waveguide surface is subjected to various glycerol concentrations. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. Exact dispersion equation is obtained in the cases of both electrically short circuit and open circuit by solving the equilibrium equations of piezoelectric materials and the Stokes equation of viscoelastic fluid. The effect on the phase velocity and attenuation for several frequencies is highlighted. The influence of key parameters such as substrate thickness and fluid thickness is also studied. These investigations can serve as benchmark solution in design of Bleustein–Gulyaev wave sensors.
Fri, 11 Dec 2020 00:00:00 GMThttp://hdl.handle.net/10985/231642020-12-11T00:00:00ZEL BAROUDI, AdilLE POMMELLEC, Jean YvesA generalized analytical approach for the propagation of Bleustein–Gulyaev wave in a piezoelectric material loaded on its surface with a viscoelastic fluid is established in this paper. The Bleustein–Gulyaev waveguide surface is subjected to various glycerol concentrations. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. Exact dispersion equation is obtained in the cases of both electrically short circuit and open circuit by solving the equilibrium equations of piezoelectric materials and the Stokes equation of viscoelastic fluid. The effect on the phase velocity and attenuation for several frequencies is highlighted. The influence of key parameters such as substrate thickness and fluid thickness is also studied. These investigations can serve as benchmark solution in design of Bleustein–Gulyaev wave sensors.Free vibration investigation of submerged thin circular plate
http://hdl.handle.net/10985/23241
Free vibration investigation of submerged thin circular plate
YANG, Xi; EL BAROUDI, Adil; LE POMMELLEC, Jean Yves
Free vibration of coupled system including clamped-free thin circular plate with hole submerged in three dimensional cylindrical container filled with inviscid, irrotational and compressible fluid is investigated in the present work. Numerical approach based on the finite element method (FEM) is performed using the Comsol Multiphysics software, in order to analyze qualitatively the vibration characteristics of the plate. Plate modeling is based on Kirchhoff-Love plate theory. Velocity potential is deployed to describe the fluid motion since the small oscillations induced by the plate vibration is considered. Bernoulli's equation together with potential theory are applied to get the fluid pressure on the free surface of the plate. To prove the reliability of the present numerical solution, a comparison is made with the results in the literature, which shows a very good agreement. Then, different parameters effect including fluid density, fluid height, free surface wave, hole radius and hole eccentricity on the natural frequencies of the coupled system is discussed in detail. Some three-dimensional mode shapes of the submerged plate are illustrated. Furthermore, the obtain results can serve as benchmark solutions for the vibration control, parameter identification and damage detection of plate.
Fri, 20 Mar 2020 00:00:00 GMThttp://hdl.handle.net/10985/232412020-03-20T00:00:00ZYANG, XiEL BAROUDI, AdilLE POMMELLEC, Jean YvesFree vibration of coupled system including clamped-free thin circular plate with hole submerged in three dimensional cylindrical container filled with inviscid, irrotational and compressible fluid is investigated in the present work. Numerical approach based on the finite element method (FEM) is performed using the Comsol Multiphysics software, in order to analyze qualitatively the vibration characteristics of the plate. Plate modeling is based on Kirchhoff-Love plate theory. Velocity potential is deployed to describe the fluid motion since the small oscillations induced by the plate vibration is considered. Bernoulli's equation together with potential theory are applied to get the fluid pressure on the free surface of the plate. To prove the reliability of the present numerical solution, a comparison is made with the results in the literature, which shows a very good agreement. Then, different parameters effect including fluid density, fluid height, free surface wave, hole radius and hole eccentricity on the natural frequencies of the coupled system is discussed in detail. Some three-dimensional mode shapes of the submerged plate are illustrated. Furthermore, the obtain results can serve as benchmark solutions for the vibration control, parameter identification and damage detection of plate.Correlation between the toroidal modes of an elastic sphere and the viscosity of liquids
http://hdl.handle.net/10985/23167
Correlation between the toroidal modes of an elastic sphere and the viscosity of liquids
LE POMMELLEC, Jean Yves; EL BAROUDI, Adil
Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate materials and mechanical properties. An analytical approach has been developed in this paper to accurately predict toroidal vibrations of an elastic nanosphere in water–glycerol mixture. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. The influence of key parameters such as glycerol mass fraction, sphere radius, and angular mode number are studied. We demonstrate that the sphere radius plays a significant role on the quality factor. Results also highlight three behavior zones: viscous fluid, transition, and elastic solid. In addition, these investigations can serve as benchmark solution in design of liquid sensors.
Fri, 26 Mar 2021 00:00:00 GMThttp://hdl.handle.net/10985/231672021-03-26T00:00:00ZLE POMMELLEC, Jean YvesEL BAROUDI, AdilVibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate materials and mechanical properties. An analytical approach has been developed in this paper to accurately predict toroidal vibrations of an elastic nanosphere in water–glycerol mixture. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. The influence of key parameters such as glycerol mass fraction, sphere radius, and angular mode number are studied. We demonstrate that the sphere radius plays a significant role on the quality factor. Results also highlight three behavior zones: viscous fluid, transition, and elastic solid. In addition, these investigations can serve as benchmark solution in design of liquid sensors.Analytical approach for predicting vibration characteristics of an embedded elastic sphere in complex fluid
http://hdl.handle.net/10985/23242
Analytical approach for predicting vibration characteristics of an embedded elastic sphere in complex fluid
YANG, Xi; EL BAROUDI, Adil; LE POMMELLEC, Jean Yves
Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing, and also to investigate the materials mechanical properties. The fluid medium surrounding the nanostructure is typically modeled as a Newtonian fluid. A novel approach based on the exact theory has been developed in this paper, to accurately predict the various vibration scenarios of an elastic sphere, in a compressible viscous fluid. Then the analysis is extended to a viscoelastic medium using the Maxwell fluid model. To demonstrate the accuracy of the present approach, a comparison is made with the published theoretical results in the literature in some particular cases, which shows a very good agreement. The effects of fluid compressibility and viscoelasticity are discussed in details and we demonstrate that the fluid compressibility plays a signi cant role in the vibration modes of an elastic sphere. Results also show that the different vibration modes of a sphere
triggers a viscoelastic response in water-glycerol mixtures similar to that of literature. In addition, the obtained results can serve as benchmark solution in design of liquid sensors.
Tue, 11 Feb 2020 00:00:00 GMThttp://hdl.handle.net/10985/232422020-02-11T00:00:00ZYANG, XiEL BAROUDI, AdilLE POMMELLEC, Jean YvesVibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing, and also to investigate the materials mechanical properties. The fluid medium surrounding the nanostructure is typically modeled as a Newtonian fluid. A novel approach based on the exact theory has been developed in this paper, to accurately predict the various vibration scenarios of an elastic sphere, in a compressible viscous fluid. Then the analysis is extended to a viscoelastic medium using the Maxwell fluid model. To demonstrate the accuracy of the present approach, a comparison is made with the published theoretical results in the literature in some particular cases, which shows a very good agreement. The effects of fluid compressibility and viscoelasticity are discussed in details and we demonstrate that the fluid compressibility plays a signi cant role in the vibration modes of an elastic sphere. Results also show that the different vibration modes of a sphere
triggers a viscoelastic response in water-glycerol mixtures similar to that of literature. In addition, the obtained results can serve as benchmark solution in design of liquid sensors.Love waves propagation in layered viscoelastic waveguides characterized by a Zener model
http://hdl.handle.net/10985/24882
Love waves propagation in layered viscoelastic waveguides characterized by a Zener model
EL BAROUDI, Adil; LE POMMELLEC, Jean Yves; COUANET, Vincent
This paper describes a theory of surface Love waves propagating in lossy waveguides consisting of a viscoelastic layer deposited on a semi-infinite elastic substrate. The Zener model to describe the viscoelastic behavior of a medium is used. This simple model captures both the relaxation and retardation. A new form of the unsteady momentum equation for viscoelastic waveguides has been established. By using appropriate boundary conditions, an analytical expression for the complex dispersion equation of Love waves has been deduced. The influence of the loss factor and the ratio of shear moduli of the surface layer on the dispersion curves of Love waves velocity and attenuation is analyzed numerically. The numerical solutions show the dependence of the velocity change and the wave attenuation in terms of the loss factor and the ratio of shear moduli. The obtained results show that the change in the ratio of shear moduli can represent a hardening or softening effect of the surface layer. These effects depend on the loss factor value of the surface layer. In addition, these results are novel, fundamental and can be applied in the characterization of the viscoelastic properties of soft biomaterials and tissues, in nondestructive testing of materials, in geophysics and seismology. Thus, the obtained complex dispersion equation can be very useful to interpret the experimental measurements of Love waves properties in viscoelastic waveguides.
Mon, 26 Feb 2024 00:00:00 GMThttp://hdl.handle.net/10985/248822024-02-26T00:00:00ZEL BAROUDI, AdilLE POMMELLEC, Jean YvesCOUANET, VincentThis paper describes a theory of surface Love waves propagating in lossy waveguides consisting of a viscoelastic layer deposited on a semi-infinite elastic substrate. The Zener model to describe the viscoelastic behavior of a medium is used. This simple model captures both the relaxation and retardation. A new form of the unsteady momentum equation for viscoelastic waveguides has been established. By using appropriate boundary conditions, an analytical expression for the complex dispersion equation of Love waves has been deduced. The influence of the loss factor and the ratio of shear moduli of the surface layer on the dispersion curves of Love waves velocity and attenuation is analyzed numerically. The numerical solutions show the dependence of the velocity change and the wave attenuation in terms of the loss factor and the ratio of shear moduli. The obtained results show that the change in the ratio of shear moduli can represent a hardening or softening effect of the surface layer. These effects depend on the loss factor value of the surface layer. In addition, these results are novel, fundamental and can be applied in the characterization of the viscoelastic properties of soft biomaterials and tissues, in nondestructive testing of materials, in geophysics and seismology. Thus, the obtained complex dispersion equation can be very useful to interpret the experimental measurements of Love waves properties in viscoelastic waveguides.