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Öğe Active control of quarter-car and bridge vibrations using the sliding mode control(Gazi Univ, Fac Engineering Architecture, 2022) Eroglu, Mustafa; Koc, Mehmet Akif; Kozan, Recep; Esen, IsmailPurpose: The aim of this study is to model the active suspension system using conventional PID and sliding mode control, which is a robust control method, in order to increase the road holding and passenger comfort (Figure A). Theory and Methods: The equations of motion of the 3-degree-of-freedom quarter-car and bridge model examined in this study were obtained by the Lagrangian method. A total of 7 second-order differential equations were obtained, including 3 equations of motion of the car and 4 equations of motion of the bridge beam. These equations are reduced to 14 first-order differential equations with the help of state space forms. Then, the Runge-Kutta method was used to solve these equations. The dynamic responses of the quarter car while passing over the bridge were analyzed with the commercial analysis program MATLAB. Results: As a result of the study, it was understood that the displacement and acceleration values of the passenger seat take their maximum values at the critical speeds of the car-bridge and car-road system. In addition, it is understood that the dynamic responses acting on the car change at some speed value of the car according to the profile of the road. Conclusion: In this study, the vertical displacement and acceleration of the passenger seat were controlled using conventional PID and sliding mode control. In addition, the dynamic interaction between the any flexible foundation and the multi-degree-of-freedom car model can be examined in more detail by using the controllers and solution method used in this study.Öğe Application of magnetic field to reduce the forced response of steel bridges to high speed train(Pergamon-Elsevier Science Ltd, 2023) Eroglu, Mustafa; Koc, Mehmet Akif; Esen, IsmailThis paper uses a train-track-bridge interaction system to assess the dynamic performance of railway bridges exposed to a high-speed train and magnetic field. A 24 degrees of freedom 3D train model and thin steel bridge beam are considered. In the interaction of train and bridge, a new six-parameter track system consisting of rail, sleeper, and ballast is modeled. The governing equations of the bridge, track and train motions are derived based on the Lagrange method. The Lorentz force induced by the directed magnetic field in the axial direction is obtained by Maxwell's equation. Using state-space forms, the second-order equations of motion are transformed into first -order differential equations, which are then solved using the Runge-Kutta method. Studies using parametric data are done to show how the suggested approach may be used to investigate the dynamic interaction of the entire system. The magnetic field intensities and moving train speed on the interaction of the railway bridge system were investigated and analyzed for the first time in the literature. Depending on the speed of the vehicle, when the dimensionless magnetic field is Hmx=30, it can be seen that the train body's vertical displacement falls by around 50%. The obtained results are helpful for the design of railway bridges and the safe and comfortable ride of high-speed trains over flexible structures.Öğe Artificial neural network application for modeling the rail rolling process(Pergamon-Elsevier Science Ltd, 2014) Altinkaya, Huseyin; Orak, Ilhami M.; Esen, IsmailRail rolling process is one of the most complicated hot rolling processes. Evaluating the effects of parametric values on this complex process is only possible through modeling. In this study, the production parameters of different types of rails in the rail rolling processes were modeled with an artificial neural network (ANN), and it was aimed to obtain optimum parameter values for a different type of rail. For this purpose, the data from the Rail and Profile Rolling Mill in Kardemir Iron & Steel Works Co. (Karabuk, Turkey) were used. BD1, BD2, and Tandem are three main parts of the rolling mill, and in order to obtain the force values of the 49 kg/m rail in each pass for the BD1 and BD2 sections, the force and torque values for the Tandem section, parameter values of 60, 54, 46, and 33 kg/m type rails were used. Comparing the results obtained from the ANN model and the actual field data demonstrated that force and torque values were obtained with acceptable error rates. The results of the present study demonstrated that ANN is an effective and reliable method to acquire data required for producing a new rail, and concerning the rail production process, it provides a productive way for accurate and fast decision making. (C) 2014 Elsevier Ltd. All rights reserved.Öğe The Casimir, Van der Waals, and electrostatic forces' effects on the response of magneto-electro-elastic nanosensor/switch beams under thermal environment(Taylor & Francis Inc, 2024) Oezmen, Ramazan; Esen, IsmailThis study investigates the impact of Casimir, Van der Waals, and electrostatic forces on nanomechanical switches' thermomechanical and free vibration behavior. The analysis is conducted using a novel higher-order beam theory and the nonlocal strain gradient elasticity. The motion equations of the nanosensor/switch beam are derived using Hamilton's principle and solved using Navier's method for general boundary conditions. The nanoswitch is composed of electroelastic barium-titanate (BaTiO3) and magnetostrictive cobalt-ferrite (CoFe2O4) materials, which are modeled using a power-law approach to account for functionally graded material property variations across the beam's thickness. The impact of different parameters, such as Casimir, Vander Waals, electrostatic forces, and variations in material composition, size parameters, and gap distance, on a nanoswitch system's bucking and free vibration is comprehensively examined. With the intermolecular and electrostatic forces, the temperature dependency of barium-titanate and cobalt-ferrite nanoswitch materials, which have not been extensively studied in any previous research, is considered in the modeling of free vibration, and the buckling behavior of a nanoswitch for the first time. This research represents the first comprehensive analysis of these factors. Considering the investigated parameters, the study's findings can provide helpful insights into developing micro/nano-electromechanical systems, including switches, sensors, and actuators.Öğe Characterization and corrosion behavior of composites reinforced with ZK60, AlN, and SiC particles(Elsevier - Division Reed Elsevier India Pvt Ltd, 2023) Sager, Abdulmuaen; Esen, Ismail; Ahlatci, Hayrettin; Turen, YunusIn this paper, microstructure, mechanical, immersion and potentiodynamic corrosion behaviours of extruded ZK60 matrix composites reinforced with forty-five lm 15% silicon carbide (SiC) particles and aluminium nitride nanoparticle (AIN) (0.2-0.5% 760 nm) were investigated. The SiC and AlN mixtures, which are the reinforcing elements of the composites, were first mixed with magnesium powder as the main alloy, then pressed under a pressure of 450 MPa and sintered at 420 degrees C. Second, the sintered compacts are placed in the ZK60 alloy matrix at the semi-solid melting temperature, and the melt is mixed mechanically. After the melts are mixed for 30 min and a homogeneous mixture is obtained, the mixtures are poured into metal moulds and composite samples are produced. After homogenization for 24 h at 400 degrees C, the composite samples were extruded at 300 degrees C with an extrusion ratio of 16:1 and a piston speed of 0.3 mm/s. Then, microstructure characterization of all composite samples was performed and potentiodynamic and immersion corrosion behaviours were analyzed in 3.5% NaCl solution. It was seen that the corrosion resistance increased depending on the percentages of SiC and AlN reinforcement elements in the matrix. As a result, it was seen that the potentiodynamic corrosion resistance of rein-forced ZK60 + 15% SiC (ZK60SiC15), ZK60 + 15% SiC + 02AIN (ZK60SiC15AlN0.2) and ZK60 + 15% SiC + 0.5% AIN (ZK60SiC15AlN0.5) compounds increased by 1.6, 1.8 and 3.5 times compared to the unre-inforced ZK60 alloy. The immersion corrosion rates were calculated as 2090.73, 1748.19, 1479.84 and 1397.79 (mg/year) for the unreinforced ZK60, ZK60SiC15, ZK60SiC15AlN0.2 and ZK60SiC15AlN0.5 rein-forcements, respectively. As a result of the SEM and elemental spectrum response analysis of the corro-sion surfaces, the presence of a layer rich in Si-O elements on the surface of the AlN + SiC reinforced composites enhanced corrosion resistance. Additionally, the formation of the Mg2Si intermetallics in the structure of the SiC reinforced composites improved corrosion resistance, according to the XRD results.(c) 2023 Karabuk University. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Creep modelling of polypropylenes using artificial neural networks trained with Bee algorithms(Pergamon-Elsevier Science Ltd, 2015) Dugenci, Muharrem; Aydemir, Alpay; Esen, Ismail; Aydin, Mehmet EminPolymeric materials, being capable of high mouldability, usability of long lifetime up to 50 years and availability at low cost properties compared to metallic materials, are in demand but finite element-based design engineers have limited means in terms of the limited material data and mathematical models. In particular, in the analysis of products with complex geometry, the stresses and strains of various amounts formed in the product should be known and evaluated in terms of a precise design of the product to fulfil life expectancy. Due to time and cost constraints, experimental data cannot be available for all cases required in analysis, therefore, finite element method-based simulations are commonly used by design engineers. This is also computationally expensive and requires a simpler and more precise way to complete the design more realistically. In this study, the whole creep behaviour of polypropylene for all stresses were obtained with 10% accuracy errors by artificial neural networks trained using existing experimental test results of the materials for a particular working range. The artificial neural network model was trained with traditional as well as heuristic based methods. It is demonstrated that heuristically trained ANN models have provided much accurate and precise results, which are in line with 10% accuracy of experimental data. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Dry Wear Behaviour of the New ZK60/AlN/SiC Particle Reinforced Composites(Mdpi, 2022) Sager, Abdulmuaen; Esen, Ismail; Ahlatci, Hayrettin; Turen, YunusThis study deals with the microstructure, mechanical, and wear properties of the extruded ZK60 matrix composites strengthened with 45 mu m, 15% silicon carbide particle (SiC) and 760 nm, 0.2-0.5% aluminium nitride (AlN) nanoparticle reinforcements. First, the reinforcement elements of the composites, SiC and AlN mixtures were prepared in master-magnesium powder, and compacts were formed under 450 MPa pressure and then sintered. Second, the compacted reinforcing elements were placed into the ZK60 alloy matrix at the semi-solid melt temperature, and the melt was mixed by mechanical mixing. After the melts were mixed for 30 min and a homogeneous mixture was formed, the mixtures were poured into metal moulds and composite samples were obtained. After being homogenized for 24 h at 400 degrees C, the alloys were extruded with a 16:1 deformation ratio at 310 degrees C and a ram speed of 0.3 mm/s to create final composite samples. After microstructure characterization and hardness analysis, the dry friction behavior of all composite samples was investigated. Depending on the percentage ratios of SIC and AlN reinforcement elements in the matrix, it was seen that the compressive strength and hardness of the composites increased, and the friction coefficient decreased. While the wear rate of the unreinforced ZK60 alloy was 3.89 x 10(-5) g/m, this value decreased by 26.2 percent to 2.87 x 10(-5) g/m in the 0.5% AlN + 15% SiC reinforced ZK 60 alloy.Öğe Dynamic analysis of FG nanobeam reinforced by carbon nanotubes and resting on elastic foundation under moving load(Taylor & Francis Inc, 2023) Abdelrahman, Alaa A.; Esen, Ismail; Daikh, Ahmed Amin; Eltaher, Mohamed A.In the context of nonclassical continuum mechanics, the nonlocal strain gradient theory is employed to develop a nonclassical size dependent model to investigate the dynamic behavior of a CNTs reinforced composite beam resting on two parameters elastic foundations under a moving load. The governing dynamic equations of motion are derived based on third-order shear deformation theory using Hamilton's principle. An analytical solution methodology is developed using Navier's procedure is developed to derive the analytical solution for the equations of motion. The developed methodology is checked and compared. Parametric studies are conducted to demonstrate the applicability of the developed procedure to investigate the dynamic behavior of CNTs beams under moving load. Effects of the elastic foundation parameters, volume fraction, CNTs configuration, the nonclassical parameters, and the moving load velocity parameter on the dynamic behavior of CNTs beams under moving load are investigated and analyzed. The obtained results are supportive for design and manufacturing of composite CNTs beams.Öğe Dynamic analysis of functionally graded (FG) nonlocal strain gradient nanobeams under thermo-magnetic fields and moving load(Techno-Press, 2022) Alazwari, Mashhour A.; Esen, Ismail; Abdelrahman, Alaa A.; Abdraboh, Azza M.; Eltaher, Mohamed A.Dynamic behavior of temperature-dependent Reddy functionally graded (RFG) nanobeam subjected to thermomagnetic effects under the action of moving point load is carried out in the present work. Both symmetric and sigmoid functionally graded material distributions throughout the beam thickness are considered. To consider the significance of strain stress gradient field, a material length scale parameter (LSP) is introduced while the significance of nonlocal elastic stress field is considered by introducing a nonlocal parameter (NP). In the framework of the nonlocal strain gradient theory (NSGT), the dynamic equations of motion are derived through Hamilton's principle. Navier approach is employed to solve the resulting equations of motion of the functionally graded (FG) nanoscale beam. The developed model is verified and compared with the available previous results and good agreement is observed. Effects of through-thickness variation of FG material distribution, beam aspect ratio, temperature variation, and magnetic field as well as the size-dependent parameters on the dynamic behavior are investigated. Introduction of the magnetic effect creates a hardening effect; therefore, higher values of natural frequencies are obtained while smaller values of the transverse deflections are produced. The obtained results can be useful as reference solutions for future dynamic and control analysis of FG nanobeams reinforced nanocomposites under thermomagnetic effects.Öğe Dynamic analysis of gun barrel vibrations due to effect of an unbalanced projectile considering 2-D transverse displacements of barrel tip using a 3-D element technique(Latin Amer J Solids Structures, 2018) Koc, Mehmet Akif; Esen, Ismail; Cay, YusufIn this paper, dynamic analysis of two different weapon systems (35 mm Anti-Aircraft Barrel (AAB) and 120 mm Grooved Tank Barrel (GTB)) under the effect of statically unbalanced projectile has been performed with a new 12 DOF 3-D element technique using Finite Element Method (FEM). The muzzle deviations, which negatively affect the barrel shooting accuracy at firing, are calculated in a time dependent manner using Newmark beta algorithm with high accuracy at both axes (yand z) considering the Coriolis centripedal and centrifugal forces. The effect of such fundamental physical parameters as shift from rotating center and angular velocity belonging to the unbalanced projectile on barrel dynamics are analyzed with this new and affective FEM. As a result, it was found out that 1% of a millimeter shift from projectile belonging to a weapon system leads to excessive vibration on both axes and compromises the shooting accuracy of the barrel.Öğe Dynamic analysis of high-speed train moving on perforated Timoshenko and Euler-Bernoulli beams(Springer Heidelberg, 2022) Koc, Mehmet Akif; Eroglu, Mustafa; Esen, IsmailThis study investigates the numerical simulation of the interaction between a high-speed train and perforated beams. The perforated bridge beam is modeled according to Timoshenko and Euler-Bernoulli beam theories with a uniform cross-section area. The high-speed dynamic model has been considered a 10-DOF multibody system. The equation of motion perforated bridge beam and high-speed train is obtained by Hamilton's principle. Then, some parameters of the perforated beam, such as different aspect ratios, the filling ratio, and the number of holes along the cross-section area, have been investigated. The frequency variation of the Timoshenko perforated beam has been evaluated according to the nondimensional parameter presented in the study, considering different filling and aspect ratios properties. Then, the mass comparison of the perforated beam with a fully solid beam has been conducted as a dynamical and statical comparison. With this method, the dynamic responses of perforated beams will be examined for the first time compared to the fully solid bridges used in previous studies in the literature. Per length mass of the perforated beam is less than the fully solid beam by the ratios of %41.51 and %30.07 in terms of dynamic and static behavior. Consequently, it has been observed that the perforated beam affects both bridge dynamic and high-speed train's dynamic.Öğe Dynamic analysis of nanoscale Timoshenko CNTs based on doublet mechanics under moving load(Springer Heidelberg, 2021) Eltaher, M. A.; Abdelrahman, Alaa A.; Esen, IsmailThe novelty of this article is to investigate the dynamic behavior and response of armchair and zigzag carbon nanotubes (CNTs) under the dynamic moving load using a bottom to up modeling nano-mechanics theory. CNTs are modeled as a Timoshenko beam structure with shear deformation effect, and the size influence of CNTs imposed using the doublet mechanics theory. Hamiltonian principle is used to derive the modified equation of motion and nonclassical boundary conditions of CNTs under moving loads. Analytical Navier method solution for simply supported CNTs beam and Newmark time integration method are developed to predict the response of the structure in time-domain. The proposed model is verified and proved with previously published works for free vibration. Parametric analysis is performed to illustrate the influence of doublet length scale, structures of CNTs, load velocities, and mass of the load on the dynamic responses of CNTs. The proposed model is useful in designing and analyzing of MEMS/NEMS, nano-sensor, and nano-actuator manufactured from CNTs.Öğe Dynamic Behavior and Force Analysis of the Full Vehicle Model using Newmark Average Acceleration Method(Eos Assoc, 2020) Yildirim, Engin; Esen, IsmailIn this study, the dynamic interaction between road and vehicle is modeled. For this purpose, a full vehicle model with eight degrees of freedom is considered. The equations of motion of the whole system are derived by the D'Alambert method and numerical solutions are obtained by the Newmark average acceleration method. Due to varying road roughness, the forces affecting the driver and the vehicle-components are analyzed in detail. Also, vertical and rotational displacements, velocities, and accelerations are examined, and results graphs are given. Two different pre-defined road profiles, created as non-random road excitation, and five different vehicle speeds are presented and analyzed.Öğe Dynamic response of a 120 mm smoothbore tank barrel during horizontal and inclined firing positions(Latin Amer J Solids Structures, 2015) Esen, Ismail; Koc, Mehmet AkifIn this study, the dynamic interaction between a 120 mm smoothbore tank barrel modeled as an Euler-Bernoulli cantilever beam and an accelerating projectile during firing is presented. The interaction was modelled using a new FEM approach that took into account the projectile's inertia, Coriolis, and centripetal forces and the horizontal and inclined positions of the barrel. The mass, exit velocity and acceleration effects of the projectile on the dynamics of the barrel were investigated. The effects of the projectile's inertia, and Coriolis and centripetal forces were evaluated as well. Furthermore, the tip displacements at different firing angles were determined by transferring the mass, stiffness and damping matrices of the barrel with the addition of the instantaneous property matrices of the projectile from a local coordinate to the global Cartesian coordinate with the aid of transformation matrices. Finally, the barrel vibrations caused by the successive firings were evaluated under different firing scenarios. To demonstrate the validity of the current study, comparisons were made with the results of previous studies and a good agreement was achieved. By using the method recommended in this study, it is possible to determine the accurate dynamic behavior of any barrel with sufficient sensitivity, without any costly or time-consuming tests being necessary.Öğe Dynamic response of a functionally graded Timoshenko beam on two-parameter elastic foundations due to a variable velocity moving mass(Pergamon-Elsevier Science Ltd, 2019) Esen, IsmailIn this study, a modified finite element method (FEM) that can be used to analyse the transverse vibrations of a Timoshenko beam, made of functionally graded materials (FGMs), on a two-parameter foundation and subjected to a variable-velocity moving mass is presented. First, the motion equations of the FGM beam exposed to a moving mass are obtained by combining the mass interaction equations with the beam equations obtained using the first-order shear deformation theory (FSDT). Secondly, to obtain the equation of motion of the beam, mass and foundations, the rigidity of the two-parameter foundations, the Winkler and shear, then combined with the motion equations of the beam and mass using the Hamilton principle. The response of the system is investigated considering the effects of inertia and variable velocity of the moving mass, parameters of the foundations and material constituents of the FGM beam. The changes on the dynamic behaviour of the FGM Timoshenko beam, which are affected by the frequency variation of the considered system are highlighted.Öğe Dynamic Response of an Overhead Crane Beam Due to a Moving Mass Using Moving Finite Element Approximation(Trans Tech Publications Ltd, 2011) Gerdemeli, Ismail; Esen, Ismail; Ozer, DeryaIn this study, dynamic behaviour of a beam system of an overhead crane is investigated. A MATLAB code is developed for numerical analyses. The moving mass on the beam is modelled as a moving finite element to include inertial effects of mass. Dynamic response of the beam is obtained depending on the mass ratio between load and beam mass. Besides, a variety of mass velocities are considered. Analysis are carried out considering mass ratio (mass of the load/mass of the beam m/M) as 0.1, 0.2, 0.4, 0.6, 0.8 and 1 and mass velocities as 1, 2, 4, 8, and 12.5 m/s. Dynamic response of the beam depends on velocity and mass of moving load. As the position of the moving mass in the span changes, it alters the natural frequency of the beam system. Generally, if the mass velocity increases, maximum beam deflection occurs far from the beam midpoint. For some values of the velocity, the maximum response may occur before the beam midpoint. At very high speeds, the maximum beam deflection occurs near the beam endpoint. At very slow speeds, the maximum beam deflection occurs near the midpoint because the system reduces to a quasi-static solution. At the same mass ratio, load velocity increases, with the increment of the beam deflection. Both mass velocity and mass ratio affects the dynamic response of the beam but the effect of velocity is greater than the mass ratio.Öğe Dynamic response of embedded Timoshenko CNTs exposed to magnetic and thermal fields subjected to moving load based on doublet mechanics(Springer Heidelberg, 2023) Ozmen, Ramazan; Esen, IsmailThis paper uses the nanomechanical theory to examine the dynamic behaviour and response of embedded zigzag and armchair carbon nanotubes (CNTs) under moving load in thermal and magnetic fields. The nanoscale size effect of CNTs is imposed using the doublet mechanics theory. The CNTs modelled as a Timoshenko beam structure with shear stress effects. The modified motion and non-classical boundary condition equations of embedded CNTs under moving load and subjected to thermal and magnetic loads are obtained using Hamilton's principle. Navier's analytical solution and Newmark's time integration methods are imposed to obtain the time domain responses of simply supported CNTs. The computational accuracy of the proposed model has been validated and proven by previously published studies for free and forced responses. In the parametric analyses, the influence of the doublet length scale parameter (DMP), armchair and zigzag structures of CNTs, moving load's velocity, magnetic field's intensity, temperature rise, and the stiffnesses of two-parameter Pasternak foundation on dynamic responses of CNTs are considered. It is obtained that the DMP significantly affects CNTs' free and forced vibration under a moving load. The DMP increase reduces system stiffness, lowering the dimensionless frequency and increasing the dynamic amplification factor. Also, the DMP has a greater influence at higher vibration modes and beam aspect ratios. The proposed modelling is helpful for the analysis, design, and remote control of MEMS/NEMS as nano-transport systems, nanosensors, and nano-actuators manufactured from CNTs.Öğe Dynamic response of FG porous nanobeams subjected thermal and magnetic fields under moving load(Techno-Press, 2022) Esen, Ismail; Alazwari, Mashhour A.; Eltaher, Mohamed A.; Abdelrahman, Alaa A.The free and live load-forced vibration behaviour of porous functionally graded (PFG) higher order nanobeams in the thermal and magnetic fields is investigated comprehensively through this work in the framework of nonlocal strain gradient theory (NLSGT). The porosity effects on the dynamic behaviour of FG nanobeams is investigated using four different porosity distribution models. These models are exploited; uniform, symmetrical, condensed upward, and condensed downward distributions. The material characteristics gradation in the thickness direction is estimated using the power-law. The magnetic field effect is incorporated using Maxwell's equations. The third order shear deformation beam theory is adopted to incorporate the shear deformation effect. The Hamilton principle is adopted to derive the coupled thermomagnetic dynamic equations of motion of the whole system and the associated boundary conditions. Navier method is used to derive the analytical solution of the governing equations. The developed methodology is verified and compared with the available results in the literature and good agreement is observed. Parametric studies are conducted to show effects of porosity parameter; porosity distribution, temperature rise, magnetic field intensity, material gradation index, non-classical parameters, and the applied moving load velocity on the vibration behavior of nanobeams. It has been showed that all the analyzed conditions have significant effects on the dynamic behavior of the nanobeams. Additionally, it has been observed that the negative effects of moving load, porosity and thermal load on the nanobeam dynamics can be reduced by the effect of the force induced from the directed magnetic field or can be kept within certain desired design limits by controlling the intensity of the magnetic field.Öğe Dynamic response of functional graded Timoshenko beams in a thermal environment subjected to an accelerating load(Elsevier, 2019) Esen, IsmailIn this study, an improved finite element method is presented which can be used to analyse the transverse and axial vibrations of the functionally graded material (FGM) beams in a thermal environment and exposed to a mass moving at variable speed. The motion equations of the FGM beam were obtained using first order shear deformation theory (FSDT). In these equations, the interaction terms of the mass inertia are derived from the exact differential of the displacement functions of the beam relative to the mass contact point. For various temperature loads (homogeneous, linear and non-linear), thermal stresses are converted to mechanical stresses and then the thermal rigidity matrix is combined with the stiffness matrix of the beam. After verification of the method, the novel findings of the interaction of the moving mass with the FGM beam in different ceramic and metallic compositions are presented for uniform, linear and non-linear thermal loads and the variable speed of the mass.Öğe Dynamic response of nonlocal strain gradient FG nanobeam reinforced by carbon nanotubes under moving point load(Springer Heidelberg, 2021) Esen, Ismail; Daikh, Ahmed Amin; Eltaher, Mohamed A.In this study, the dynamic behavior of composite beams reinforced by carbon nanotubes (CNTs) exposed to a mass moving is investigated. By considering the external potential energy due to the applied moving mass, the equations of motion of the CNT-reinforced beam are obtained using Hamilton's principle by combining Reddy's third-order shear deformation theory and nonlocal strain gradient theory. Three types of aligned CNT-reinforced beams are considered, namely uniformly distributed CNT beams (UD-CNT) and functionally graded CNT beams type ? (FG?-CNT), and type X (FGX-CNT). Navier's procedure is applied to obtain the closed-form solutions of simply supported CNT-reinforced beams. Verification of the present solution with previous works is presented. A detailed parametric analysis is carried out to highlight the impact of moving load velocity, nonlocal parameter, material scale parameter, total volume fraction and CNTs distribution patterns on the midspan deflections of CNTs-reinforced composite beams. The proposed model is useful in the designing and analyzing of MEMS/NEMS, nanosensor, and nanoactuator manufactured from CNTs.
