Majid Ghadiri - Academia.edu (original) (raw)

Papers by Majid Ghadiri

Transportation Research Record: Journal of the Transportation Research Board

The purpose of this study was to obtain the shape and material of a rubber sinusoidal rumble stri... more The purpose of this study was to obtain the shape and material of a rubber sinusoidal rumble strip that reduces the noise produced outside the vehicle and does not affect the sound and vibration performance inside the vehicle. Considering the role of rubber rumble strips in reducing the noise created outside the car and also the vibration and sound produced inside the car, software simulation and field study were used to achieve the desired results. Car performance modeling has been done in Simulink software in the form of signal response of wheels and car body to bumps. By the field tests, the grooved and raised rumble strips commonly used on road surfaces, as well as the prefabricated sinusoidal rumble strips produced of crush rubber with dimensions taken from the simulation test, were tested. For 100 km/h speed, conventional grooved strips and sinusoidal strips with wavelengths of 35 cm and amplitudes of 0.6 cm and 1 cm have yielded the highest values of vibration amplitude. For ...

Applied Mathematical Modelling, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Journal of Solid Mechanics, 2017

The nanostructures under rotation have high promising future to be used in nano-machines, nano-mo... more The nanostructures under rotation have high promising future to be used in nano-machines, nano-motors and nano-turbines. They are also one of the topics of interests and it is new in designing of rotating nano-systems. In this paper, the scale-dependent vibration analysis of a nanoplate with consideration of the axial force due to the rotation has been investigated. The governing equation and boundary conditions are derived using the Hamilton’s principle based on nonlocal elasticity theory. The boundary conditions of the nanoplate are considered as free-free in y direction and two clamped-free (cantilever plate) and clamped-simply (propped cantilever) in x direction. The equations have been solved using differential quadrature method to determine natural frequencies of the rotating nanoplate. For validation, in special cases, it has been shown that the obtained results coincide with literatures. The effects of the nonlocal parameter, aspect ratio, hub radius, angular velocity and di...

This paper investigates the effect of a non-ideal support on free vibration of an Euler-Bernoulli... more This paper investigates the effect of a non-ideal support on free vibration of an Euler-Bernoulli composite beam carrying a mass-spring-damper system under an axial force. The beam simply supported boundary conditions and it is assumed that one of its supports is non-ideal. Therefore, it has a small non-zero deflection and a small non-zero moment. The governing equations of the problem constitute a coupled system including a PDE and an ODE. To solve the problem, the Galerkin method is employed in the displacement field in conjunction with the average acceleration method in the time domain. The effect of a non-ideal support of composite beam, under axial force on natural frequencies and mode shapes of the system, is studied in details. For the validation of the performed solution and the obtained results, in a special case, the fundamental frequency was compared with those cited in the literature. The obtained results show that with increasing the perturbation parameter, the fundamen...

Journal of Solid Mechanics, 2021

This paper represented a numerical technique for discovering the vibrational behavior of a two-di... more This paper represented a numerical technique for discovering the vibrational behavior of a two-directional FGM (2-FGM) nanobeam exposed to thermal load for the first time. Mechanical attributes of two-directional FGM (2-FGM) nanobeam are changed along the thickness and length directions of nanobeam. The nonlocal Eringen parameter is taken into the nonlocal elasticity theory (NET). Uniform temperature rise (UTR), linear temperature rise (LTR), non-linear temperature rise (NLTR) and sinusoidal temperature rise (STR) during the thickness and length directions of nanobeam is analyzed. Third-order shear deformation theory (TSDT) is used to derive the governing equations of motion and associated boundary conditions of the two-directional FGM (2-FGM) nanobeam via Hamilton’s principle. The differential quadrature method (DQM) is employed to achieve the natural frequency of two-directional FGM (2-FGM) nanobeam. A parametric study is led to assess the efficacy of coefficients of two-direction...

Journal of Solid Mechanics, 2019

In this research, the effect of rotation on the free vibration is investigated for the size-depen... more In this research, the effect of rotation on the free vibration is investigated for the size-dependent cylindrical functionally graded (FG) nanoshell by means of the modified couple stress theory (MCST). MCST is applied to make the design and the analysis of nano actuators and nano sensors more reliable. Here the equations of motion and boundary conditions are derived using minimum potential energy principle and first-order shear deformation theory (FSDT). The formulation consists of the Coriolis, centrifugal and initial hoop tension effects due to the rotation. The accuracy of the presented model is verified with literatures. The novelty of this study is the consideration of the rotation effects along with the satisfaction of various boundary conditions. Generalized differential quadrature method (GDQM) is employed to discretize the equations of motion. Then the investigation has been made into the influence of some factors such as the material length scale parameter, angular veloci...

This paper represented a numerical technique for discovering the vibrational behavior of a two-di... more This paper represented a numerical technique for discovering the vibrational behavior of a two-directional FGM (2-FGM) Nano beam exposed to thermal load for the first time. Mechanical attributes of two-directional FGM (2-FGM) Nano beam are changed along the thickness and length directions of nanobeam. The nonlocal Eringen parameter is taken into the nonlocal elasticity theory (NET). Uniform temperature rise (UTR), linear temperature rise (LTR), non-linear temperature rise (NLTR) and sinusoidal temperature rise (STR) during the thickness and length directions of Nano beam is analyzed. Third-order shear deformation theory (TSDT) is used to derive the governing equations of motion and associated boundary conditions of the two-directional FGM (2FGM) Nano beam via Hamilton’s principle. The differential quadrature method (DQM) is employed to achieve the natural frequency of two-directional FGM (2-FGM) Nano beam. A parametric study is led to assess the efficacy of coefficients of twodirect...

Steel and Composite Structures, 2017

In this paper, Coriolis effect on vibration behavior of a rotating rectangular plate made of func... more In this paper, Coriolis effect on vibration behavior of a rotating rectangular plate made of functionally graded (FG) materials under thermal loading has been investigated. The material properties of the FG plate are supposed to get changed in parallel with the thickness of the plate and the thermal properties of the material are assumed to be thermo-elastic. In this research, the effect of hub size, rotating speed and setting angle are considered. Governing equation of motion and the associated boundary conditions are obtained by Hamilton's principle. Generalized differential quadrature method (GDQM) is used to solve the governing differential equation with respect to cantilever boundary condition. The results were successfully verified with the published literatures. These results can be useful for designing rotary systems such as turbine blades. In this work, Coriolis and thermal effects are considered for the first time and GDQM method has been used in solving the equations ...

Acta Biomaterialia, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Mechanics Based Design of Structures and Machines, 2019

Knowing the size-dependent parameters is essential in continuum modeling of micro/nanostructures.... more Knowing the size-dependent parameters is essential in continuum modeling of micro/nanostructures. In this paper, nonlocal and material length scale parameters are calibrated by comparing the natural frequencies obtained from MD simulation and nonlocal strain gradient theory. Elastic modulus of each CNT is also calculated by MD and used in the shell model. The effects of size-dependent parameters on the natural frequency and their dependency on geometry and chirality of CNTs are also investigated. It is found that in the calibration of continuum results with MD outputs, the nonlocal parameter has the dominant effect in comparison with material length scale parameter..

Journal of Intelligent Material Systems and Structures, 2018

In this article, the free vibration of a rotating two-directional functionally graded porous magn... more In this article, the free vibration of a rotating two-directional functionally graded porous magnetoelastic nanosize circular plate is analytically studied. The presented model incorporates effects of the small-scale parameter and external magnetic loading. In contrast to the previous works, the material properties of the circular nanoplate are considered to be functionally graded in both thickness and radial directions. In addition, the magnetic actuation is also taken into account in the analysis. By using Hamilton’s principle and employing the modified couple stress theory, the governing equations and boundary conditions are derived based on the first-order shear deformation theory. The derived equations are solved by using the differential quadrature method. The validity of the present analysis is confirmed by comparing the obtained results with the results existed in the literature. A detailed parametric study is conducted to highlight the influences of the boundary conditions ...

Mechanical Systems and Signal Processing, 2019

The study of the instability created by the pull-in voltage on electrostatic NEMS/MEMS devices ha... more The study of the instability created by the pull-in voltage on electrostatic NEMS/MEMS devices have been studied by many researchers during the recent years. In the present study, considering the effects of Casimir force and fringing field, for the first time the pull-in instability of a Magnetorheological elastomer (MRE) sandwich cantilever MEMS actuator with conductive skins is investigated. The governing equations and the related boundary conditions are obtained through variational principle based on the Euler-Bernoulli beam theory. The obtained equations are solved using the generalized differential quadrature (GDQ) method. The MREs are smart materials which, by applying the magnetic field on them, their shear modulus can be changed and it's possible to control the stiffness of structures which use these materials as nuclei. By applying different magnetic fields, the results show a decrease in the deflection of the movable electrode and this causes the electrode to become unstable at higher voltages, in other words, as the magnetic field increases the pull-in voltage also increases. Using sandwich structures with MRE core to create cantilever MEMS actuator, the pull-in voltage control is created for this tool.

Applied Mathematics and Mechanics, 2014

The antiplane stress analysis of two anisotropic finite wedges with arbitrary radii and apex angl... more The antiplane stress analysis of two anisotropic finite wedges with arbitrary radii and apex angles that are bonded together along a common edge is investigated. The wedge radial boundaries can be subjected to displacement-displacement boundary conditions, and the circular boundary of the wedge is free from any traction. The new finite complex transforms are employed to solve the problem. These finite complex transforms have complex analogies to both kinds of standard finite Mellin transforms. The traction free condition on the crack faces is expressed as a singular integral equation by using the exact analytical method. The explicit terms for the strength of singularity are extracted, showing the dependence of the order of the stress singularity on the wedge angle, material constants, and boundary conditions. A numerical method is used for solving the resultant singular integral equations. The displacement boundary condition may be a general term of the Taylor series expansion for the displacement prescribed on the radial edge of the wedge. Thus, the analysis of every kind of displacement boundary conditions can be obtained by the achieved results from the foregoing general displacement boundary condition. The obtained stress intensity factors (SIFs) at the crack tips are plotted and compared with those obtained by the finite element analysis (FEA).

Journal of Vibration and Control, 2016

This study investigates the small-scale effect on the flapwise bending vibrations of a rotating n... more This study investigates the small-scale effect on the flapwise bending vibrations of a rotating nanoplate that can be the basis of nano-turbine design. The nanoplate is modeled as classical plate theory (CPT) with boundary conditions as the cantilever and propped cantilever. The axial forces are also included in the model as the true spatial variation due to the rotation. Hamilton’s principle is used to derive the governing equation and boundary conditions for the classic plate based on Eringen’s nonlocal elasticity theory and the differential quadrature method is employed to solve the governing equations. The effect of the small-scale parameter, nondimensional angular velocity, nondimensional hub radius, setting angle and different boundary conditions in the first four nondimensional frequencies is discussed. Due to considering rotating effects, results of this study are applicable in nanomachines such as nanomotors and nano-turbines and other nanostructures.

Journal of Solid Mechanics, 2020

In this paper, vibration analysis of rotary tapered axially functionally graded (AFG) Timoshenko ... more In this paper, vibration analysis of rotary tapered axially functionally graded (AFG) Timoshenko nanobeam is investigated in a thermal environment based on nonlocal theory. The governing equations of motion and the related boundary conditions are derived by means of Hamilton’s principle based on the first order shear deformation theory of beams. The solution method is considered using generalized differential quadrature element (GDQE) method. The accuracy of results are validated by other results reported in other references. The effect of various parameters such as AFG index, rate of cross section change, angular velocity, size effect and boundary conditions on natural frequencies are discussed comprehensively. The results show that with increasing angular velocity, non-dimensional frequency is increased and it depends on size effect parameter. Also, in the zero angular velocity, it can be seen with increasing AFG index, the frequencies are reducing, but in non-zero angular velocit...

International Journal of Mechanical Sciences

Journal of Intelligent Material Systems and Structures

In this article, a first-order shear deformable model is expanded based on the nonlocal strain gr... more In this article, a first-order shear deformable model is expanded based on the nonlocal strain gradient theory to vibration analysis of smart nanostructures under different boundary conditions. The governing equations of motion of rotating magneto-viscoelastic functionally graded cylindrical nanoshell in the magnetic field and corresponding boundary conditions are obtained using Hamilton’s principle. To discretize the equations of motion, the generalized differential quadrature method is applied. The aim of this work is to investigate the effects of the temperature changes, nonlocal parameter, material length scale, viscoelastic coefficient, various boundary conditions, and the rotational speed of this smart structure on natural frequencies of rotating cylindrical nanoshell made of magneto-viscoelastic functionally graded material.

Mechanics of Advanced Materials and Structures

Applied Mathematical Modelling

Mechanics of Advanced Materials and Structures

Transportation Research Record: Journal of the Transportation Research Board

The purpose of this study was to obtain the shape and material of a rubber sinusoidal rumble stri... more The purpose of this study was to obtain the shape and material of a rubber sinusoidal rumble strip that reduces the noise produced outside the vehicle and does not affect the sound and vibration performance inside the vehicle. Considering the role of rubber rumble strips in reducing the noise created outside the car and also the vibration and sound produced inside the car, software simulation and field study were used to achieve the desired results. Car performance modeling has been done in Simulink software in the form of signal response of wheels and car body to bumps. By the field tests, the grooved and raised rumble strips commonly used on road surfaces, as well as the prefabricated sinusoidal rumble strips produced of crush rubber with dimensions taken from the simulation test, were tested. For 100 km/h speed, conventional grooved strips and sinusoidal strips with wavelengths of 35 cm and amplitudes of 0.6 cm and 1 cm have yielded the highest values of vibration amplitude. For ...

Applied Mathematical Modelling, 2021

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Journal of Solid Mechanics, 2017

The nanostructures under rotation have high promising future to be used in nano-machines, nano-mo... more The nanostructures under rotation have high promising future to be used in nano-machines, nano-motors and nano-turbines. They are also one of the topics of interests and it is new in designing of rotating nano-systems. In this paper, the scale-dependent vibration analysis of a nanoplate with consideration of the axial force due to the rotation has been investigated. The governing equation and boundary conditions are derived using the Hamilton’s principle based on nonlocal elasticity theory. The boundary conditions of the nanoplate are considered as free-free in y direction and two clamped-free (cantilever plate) and clamped-simply (propped cantilever) in x direction. The equations have been solved using differential quadrature method to determine natural frequencies of the rotating nanoplate. For validation, in special cases, it has been shown that the obtained results coincide with literatures. The effects of the nonlocal parameter, aspect ratio, hub radius, angular velocity and di...

This paper investigates the effect of a non-ideal support on free vibration of an Euler-Bernoulli... more This paper investigates the effect of a non-ideal support on free vibration of an Euler-Bernoulli composite beam carrying a mass-spring-damper system under an axial force. The beam simply supported boundary conditions and it is assumed that one of its supports is non-ideal. Therefore, it has a small non-zero deflection and a small non-zero moment. The governing equations of the problem constitute a coupled system including a PDE and an ODE. To solve the problem, the Galerkin method is employed in the displacement field in conjunction with the average acceleration method in the time domain. The effect of a non-ideal support of composite beam, under axial force on natural frequencies and mode shapes of the system, is studied in details. For the validation of the performed solution and the obtained results, in a special case, the fundamental frequency was compared with those cited in the literature. The obtained results show that with increasing the perturbation parameter, the fundamen...

Journal of Solid Mechanics, 2021

This paper represented a numerical technique for discovering the vibrational behavior of a two-di... more This paper represented a numerical technique for discovering the vibrational behavior of a two-directional FGM (2-FGM) nanobeam exposed to thermal load for the first time. Mechanical attributes of two-directional FGM (2-FGM) nanobeam are changed along the thickness and length directions of nanobeam. The nonlocal Eringen parameter is taken into the nonlocal elasticity theory (NET). Uniform temperature rise (UTR), linear temperature rise (LTR), non-linear temperature rise (NLTR) and sinusoidal temperature rise (STR) during the thickness and length directions of nanobeam is analyzed. Third-order shear deformation theory (TSDT) is used to derive the governing equations of motion and associated boundary conditions of the two-directional FGM (2-FGM) nanobeam via Hamilton’s principle. The differential quadrature method (DQM) is employed to achieve the natural frequency of two-directional FGM (2-FGM) nanobeam. A parametric study is led to assess the efficacy of coefficients of two-direction...

Journal of Solid Mechanics, 2019

In this research, the effect of rotation on the free vibration is investigated for the size-depen... more In this research, the effect of rotation on the free vibration is investigated for the size-dependent cylindrical functionally graded (FG) nanoshell by means of the modified couple stress theory (MCST). MCST is applied to make the design and the analysis of nano actuators and nano sensors more reliable. Here the equations of motion and boundary conditions are derived using minimum potential energy principle and first-order shear deformation theory (FSDT). The formulation consists of the Coriolis, centrifugal and initial hoop tension effects due to the rotation. The accuracy of the presented model is verified with literatures. The novelty of this study is the consideration of the rotation effects along with the satisfaction of various boundary conditions. Generalized differential quadrature method (GDQM) is employed to discretize the equations of motion. Then the investigation has been made into the influence of some factors such as the material length scale parameter, angular veloci...

This paper represented a numerical technique for discovering the vibrational behavior of a two-di... more This paper represented a numerical technique for discovering the vibrational behavior of a two-directional FGM (2-FGM) Nano beam exposed to thermal load for the first time. Mechanical attributes of two-directional FGM (2-FGM) Nano beam are changed along the thickness and length directions of nanobeam. The nonlocal Eringen parameter is taken into the nonlocal elasticity theory (NET). Uniform temperature rise (UTR), linear temperature rise (LTR), non-linear temperature rise (NLTR) and sinusoidal temperature rise (STR) during the thickness and length directions of Nano beam is analyzed. Third-order shear deformation theory (TSDT) is used to derive the governing equations of motion and associated boundary conditions of the two-directional FGM (2FGM) Nano beam via Hamilton’s principle. The differential quadrature method (DQM) is employed to achieve the natural frequency of two-directional FGM (2-FGM) Nano beam. A parametric study is led to assess the efficacy of coefficients of twodirect...

Steel and Composite Structures, 2017

In this paper, Coriolis effect on vibration behavior of a rotating rectangular plate made of func... more In this paper, Coriolis effect on vibration behavior of a rotating rectangular plate made of functionally graded (FG) materials under thermal loading has been investigated. The material properties of the FG plate are supposed to get changed in parallel with the thickness of the plate and the thermal properties of the material are assumed to be thermo-elastic. In this research, the effect of hub size, rotating speed and setting angle are considered. Governing equation of motion and the associated boundary conditions are obtained by Hamilton's principle. Generalized differential quadrature method (GDQM) is used to solve the governing differential equation with respect to cantilever boundary condition. The results were successfully verified with the published literatures. These results can be useful for designing rotary systems such as turbine blades. In this work, Coriolis and thermal effects are considered for the first time and GDQM method has been used in solving the equations ...

Acta Biomaterialia, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Mechanics Based Design of Structures and Machines, 2019

Knowing the size-dependent parameters is essential in continuum modeling of micro/nanostructures.... more Knowing the size-dependent parameters is essential in continuum modeling of micro/nanostructures. In this paper, nonlocal and material length scale parameters are calibrated by comparing the natural frequencies obtained from MD simulation and nonlocal strain gradient theory. Elastic modulus of each CNT is also calculated by MD and used in the shell model. The effects of size-dependent parameters on the natural frequency and their dependency on geometry and chirality of CNTs are also investigated. It is found that in the calibration of continuum results with MD outputs, the nonlocal parameter has the dominant effect in comparison with material length scale parameter..

Journal of Intelligent Material Systems and Structures, 2018

In this article, the free vibration of a rotating two-directional functionally graded porous magn... more In this article, the free vibration of a rotating two-directional functionally graded porous magnetoelastic nanosize circular plate is analytically studied. The presented model incorporates effects of the small-scale parameter and external magnetic loading. In contrast to the previous works, the material properties of the circular nanoplate are considered to be functionally graded in both thickness and radial directions. In addition, the magnetic actuation is also taken into account in the analysis. By using Hamilton’s principle and employing the modified couple stress theory, the governing equations and boundary conditions are derived based on the first-order shear deformation theory. The derived equations are solved by using the differential quadrature method. The validity of the present analysis is confirmed by comparing the obtained results with the results existed in the literature. A detailed parametric study is conducted to highlight the influences of the boundary conditions ...

Mechanical Systems and Signal Processing, 2019

The study of the instability created by the pull-in voltage on electrostatic NEMS/MEMS devices ha... more The study of the instability created by the pull-in voltage on electrostatic NEMS/MEMS devices have been studied by many researchers during the recent years. In the present study, considering the effects of Casimir force and fringing field, for the first time the pull-in instability of a Magnetorheological elastomer (MRE) sandwich cantilever MEMS actuator with conductive skins is investigated. The governing equations and the related boundary conditions are obtained through variational principle based on the Euler-Bernoulli beam theory. The obtained equations are solved using the generalized differential quadrature (GDQ) method. The MREs are smart materials which, by applying the magnetic field on them, their shear modulus can be changed and it's possible to control the stiffness of structures which use these materials as nuclei. By applying different magnetic fields, the results show a decrease in the deflection of the movable electrode and this causes the electrode to become unstable at higher voltages, in other words, as the magnetic field increases the pull-in voltage also increases. Using sandwich structures with MRE core to create cantilever MEMS actuator, the pull-in voltage control is created for this tool.

Applied Mathematics and Mechanics, 2014

The antiplane stress analysis of two anisotropic finite wedges with arbitrary radii and apex angl... more The antiplane stress analysis of two anisotropic finite wedges with arbitrary radii and apex angles that are bonded together along a common edge is investigated. The wedge radial boundaries can be subjected to displacement-displacement boundary conditions, and the circular boundary of the wedge is free from any traction. The new finite complex transforms are employed to solve the problem. These finite complex transforms have complex analogies to both kinds of standard finite Mellin transforms. The traction free condition on the crack faces is expressed as a singular integral equation by using the exact analytical method. The explicit terms for the strength of singularity are extracted, showing the dependence of the order of the stress singularity on the wedge angle, material constants, and boundary conditions. A numerical method is used for solving the resultant singular integral equations. The displacement boundary condition may be a general term of the Taylor series expansion for the displacement prescribed on the radial edge of the wedge. Thus, the analysis of every kind of displacement boundary conditions can be obtained by the achieved results from the foregoing general displacement boundary condition. The obtained stress intensity factors (SIFs) at the crack tips are plotted and compared with those obtained by the finite element analysis (FEA).

Journal of Vibration and Control, 2016

This study investigates the small-scale effect on the flapwise bending vibrations of a rotating n... more This study investigates the small-scale effect on the flapwise bending vibrations of a rotating nanoplate that can be the basis of nano-turbine design. The nanoplate is modeled as classical plate theory (CPT) with boundary conditions as the cantilever and propped cantilever. The axial forces are also included in the model as the true spatial variation due to the rotation. Hamilton’s principle is used to derive the governing equation and boundary conditions for the classic plate based on Eringen’s nonlocal elasticity theory and the differential quadrature method is employed to solve the governing equations. The effect of the small-scale parameter, nondimensional angular velocity, nondimensional hub radius, setting angle and different boundary conditions in the first four nondimensional frequencies is discussed. Due to considering rotating effects, results of this study are applicable in nanomachines such as nanomotors and nano-turbines and other nanostructures.

Journal of Solid Mechanics, 2020

In this paper, vibration analysis of rotary tapered axially functionally graded (AFG) Timoshenko ... more In this paper, vibration analysis of rotary tapered axially functionally graded (AFG) Timoshenko nanobeam is investigated in a thermal environment based on nonlocal theory. The governing equations of motion and the related boundary conditions are derived by means of Hamilton’s principle based on the first order shear deformation theory of beams. The solution method is considered using generalized differential quadrature element (GDQE) method. The accuracy of results are validated by other results reported in other references. The effect of various parameters such as AFG index, rate of cross section change, angular velocity, size effect and boundary conditions on natural frequencies are discussed comprehensively. The results show that with increasing angular velocity, non-dimensional frequency is increased and it depends on size effect parameter. Also, in the zero angular velocity, it can be seen with increasing AFG index, the frequencies are reducing, but in non-zero angular velocit...

International Journal of Mechanical Sciences

Journal of Intelligent Material Systems and Structures

In this article, a first-order shear deformable model is expanded based on the nonlocal strain gr... more In this article, a first-order shear deformable model is expanded based on the nonlocal strain gradient theory to vibration analysis of smart nanostructures under different boundary conditions. The governing equations of motion of rotating magneto-viscoelastic functionally graded cylindrical nanoshell in the magnetic field and corresponding boundary conditions are obtained using Hamilton’s principle. To discretize the equations of motion, the generalized differential quadrature method is applied. The aim of this work is to investigate the effects of the temperature changes, nonlocal parameter, material length scale, viscoelastic coefficient, various boundary conditions, and the rotational speed of this smart structure on natural frequencies of rotating cylindrical nanoshell made of magneto-viscoelastic functionally graded material.

Mechanics of Advanced Materials and Structures

Applied Mathematical Modelling

Mechanics of Advanced Materials and Structures