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Article
Publication date: 16 October 2024

Mehdi Ranjbar-Roeintan, Sajad Ahmadian and Ali Soleymani

The study aims to predict a low-velocity impact on a plate reinforced with carbon nanotubes (CNTs) using machine learning models.

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Abstract

Purpose

The study aims to predict a low-velocity impact on a plate reinforced with carbon nanotubes (CNTs) using machine learning models.

Design/methodology/approach

The first-order shear deformation plate theory (FSDT) is used to express the plate displacements filed. The Hertz nonlinear contact law is used to predict the contact between impactor and plate. Using the energy method and Hamilton’s principle, the motion equations are extracted. The six main parameters considered as inputs to machine learning models are CNTs percentage, impactor radius, plate thickness, plate length and width, CNTs distribution profile and impactor initial velocity. These input parameters are used to predict two impact targets including contact force and contact time.

Findings

As the values of the targets are continuous, the machine learning task is considered a regression problem. Therefore, this study uses different regression models to predict the targets. These regression models include linear regression, stochastic gradient descent regressor, Bayesian regression, partial least squares regression, Gaussian process regression, multilayer perceptron regressor, support vector regression and decision tree regression. To validate the effectiveness of the regression models, experiments are designed based on different evaluation metrics. The results of the experiments demonstrate that the machine learning models achieve promising performance in predicting the contact force and contact time based on the input parameters.

Originality/value

Due to the volume of high numerical calculations of impact mechanics to reach the response, the targets of the impact problem are predicted using a variety of machine learning methods.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 14 December 2020

Raed Salman Saeed Alhusseini, Ali Sadik Gafer Qanber, Bashar Dheyaa Hussein Al-Kasob, Manar Hamid Jasim and Mehdi Ranjbar

This paper aims to present the potential of using aligned single-layer graphene sheets to reinforce the methyl methacrylate cantilever beam in low-velocity impact problem.

53

Abstract

Purpose

This paper aims to present the potential of using aligned single-layer graphene sheets to reinforce the methyl methacrylate cantilever beam in low-velocity impact problem.

Design/methodology/approach

The Halpin–Tsai law is applied to compute the mechanical properties of isotropic polymer beam reinforced by aligned graphene sheet. Using both longitudinal and lateral displacements in composite beam, all components of the stress and strain fields are written. The equations of motion are derived by applying energy method, generalized Lagrange equations and Ritz method.

Findings

The analytical formulation accuracy is corroborated by comparing the present results with those available in the literature. Numerical examples indicate that the contact duration is decreased with increasing of graphene volume fraction, whereas the values of peak contact force, shear strain and shear stress at peak contact force tend to be vice versa. Also, among the results, shear stress at the peak contact force has the most effect with graphene volume fraction changes.

Originality/value

This research fulfils an identified need to investigate how graphene-reinforced beam behavior subjected to low-velocity impact can be enabled.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 20 May 2020

Ali Sadik Gafer Qanber, Raed Salman Saeed Alhusseini, Bashar Dheyaa Hussein Al-Kasob, Manar Hamid Jasim and Mehdi Ranjbar

The main objective of this article is to develop a theoretical formulation for predicting the response of CNTs reinforced beam under multiple impactors with general boundary…

72

Abstract

Purpose

The main objective of this article is to develop a theoretical formulation for predicting the response of CNTs reinforced beam under multiple impactors with general boundary conditions, using first-order shear deformation beam theory.

Design/methodology/approach

The rule of mixtures is implemented to derive the material properties of the beam. The nonlinear Hertz contact law is applied for simulation between impactors and the surface of the beam. A combination of approaches includes energy method, Ritz method and generalized Lagrange equations are used to extract the matrix form of equations of motion. The time-domain solution is obtained using implementing the well-known Runge Kutta 4th order method.

Findings

After examining the accuracy of the present method, the effects of the number of impactors include one impactor, and three impactors in various CNTs volume fraction are studied for CNTs reinforced beam with clamped-clamped, clamped-free and simply supported boundary conditions under the low-velocity impact. The most important finding of this article is that contact force and beam indentation at the middle of the beam in the case of one impactor are greater than those reported in the case of three impactors.

Originality/value

This article fulfills an identified need to study how CNTs reinforced beam behaviour with general boundary conditions under multiple low-velocity impacts can be enabled.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 1
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 5 October 2021

Mohammed Salih Hassan, Haideer Taleb Shomran, Abbas Allawi Abbas, Bashar Dheyaa Hussein Al-Kasob, Manar Hamid Jasim and Mehdi Ranjbar

The purpose of this paper is to investigate the effect of graphene platelets (GPLs) on the low-speed contact between a mass and surface of a multi-layer polymer beam.

91

Abstract

Purpose

The purpose of this paper is to investigate the effect of graphene platelets (GPLs) on the low-speed contact between a mass and surface of a multi-layer polymer beam.

Design/methodology/approach

This problem is primarily organized by first-order shear deformation beam theory and nonlinear Hertz rule. GPLs are distributed along the beam thickness direction. The Halpin–Tsai micromechanics model is applied for computing the effective Young’s modulus of the GPLs/polymer composites. In the formulation process, the principle of conservation of energy is first used and the histories of results are extracted using the separation of variables and Runge–Kutta method.

Findings

In comparing the responses with the available data, a good agreement is observed. The effects of the weight fraction and distribution pattern on the impact response of polymer beam reinforced with GPLs are studied. Results show that contact force is increased, contact time and beam recess are decreased with increasing of weight fraction of GPLs. Also, among the different distribution patterns, the contact force depended on value of GPLs at the point of contact.

Originality/value

The effects of GPLs addition on the multi-layer polymer beam has a novelty in impact problems.

Details

Pigment & Resin Technology, vol. 51 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 24 June 2020

Manar Hamid Jasim, Ali Mohammad Ali Al-Araji, Bashar Dheyaa Hussein Al-Kasob and Mehdi Ranjbar

In the article, analytical model of first-order shear deformation (FSDT) beams made of jute–epoxy is presented to study the low-velocity impact response.

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Abstract

Purpose

In the article, analytical model of first-order shear deformation (FSDT) beams made of jute–epoxy is presented to study the low-velocity impact response.

Design/methodology/approach

The nonlinear Hertz contact law is applied to identify the contact between projectile and beam. The energy method, Lagrange's equations and Ritz method are applied to derive the nonlinear governing equation of the beam and impactor-associated boundary condition. The motion equations are then solved simultaneously by the Runge–Kutta fourth-order method.

Findings

Also, a comparison is performed to validate the model predictions. The contact force and beam indentation histories of the jute–epoxy simply supported beam under spherical impactor with different radius and initial velocity are investigated in detail. It is found that in response to impactor radius increase, the utilization of the contact force law has resulted in a same increasing trend of peak contact force, impact duration and beam indentation, while in response to impactor initial velocity increase, the maximum contact force and beam indentation increase while impact time has vice versa trend.

Originality/value

This paper fulfills an identified need to study how jute–epoxy beam behavior with simply supported boundary conditions under low-velocity impact can be enabled.

Details

International Journal of Structural Integrity, vol. 12 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 18 February 2025

Shapour Ebrahimi, Saeed Feli and Mehdi Ranjbar-Roeintan

The purpose of this paper is to use three-dimensional printers to fabricate functionally graded porous (FGP) beams, carry out impact loading and provide innovative equations.

2

Abstract

Purpose

The purpose of this paper is to use three-dimensional printers to fabricate functionally graded porous (FGP) beams, carry out impact loading and provide innovative equations.

Design/methodology/approach

In this study, using the three-dimensional printer, polylactic acid beams containing internal holes with distribution two-dimensional FGP beams of type X are fabricated. A simple tensile test and also a drop-weight impact test are performed to determine the mechanical and low-velocity impact properties of the beams. Inverse-tangent shear–strain function theory, together with the energy method, is used to derive the motion equations of low-velocity impact on the beam. A range of impact energies from 1.5 to 12 J and holes with diameters of 2 and 3 mm are used in the drop-weight impact testing machine.

Findings

As the hole diameter enlarges, there is a decrease in contact force and energy absorption levels. The larger hole diameter results in an extended contact duration, increased maximum impactor displacement, and a higher remaining impactor velocity. The innovative linear equations with a maximum error of 5.18% and nonlinear equations with a maximum error of 0.01% provide an acceptable result for the maximum contact force. For predicting the absorbed energy, the linear equation with a maximum error of 90.69% does provide an unacceptable result, and the nonlinear equation with a maximum error of 4.51% provides a reasonable result.

Originality/value

The originality of this research is in fabricating FGP beams with a three-dimensional printer to conduct impact tests and generate creative equations.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 6 June 2023

Mehdi Ranjbar-Roeintan

This article focuses on the low-velocity impact (LVI) output of carbon nanotubes (CNTs)’ reinforcement circular plates, considering agglomeration size effect and clumping of CNTs’…

42

Abstract

Purpose

This article focuses on the low-velocity impact (LVI) output of carbon nanotubes (CNTs)’ reinforcement circular plates, considering agglomeration size effect and clumping of CNTs’ inner side of the agglomerations.

Design/methodology/approach

A representative volume element (RVE) is used to determine the nanocomposite properties reinforced with agglomerated CNTs with random orientation. First-order shear deformation theory (FSDT) is used to obtain the motion equations of LVI analysis. These equations are handled by developing a Ritz method and Lagrangian mechanics. To extract the mass and stiffness matrices, terms with second and higher degrees are ignored.

Findings

Formulation validation is performed by providing various examples, including comparisons with other research and ABAQUS FE code. The effects of agglomeration size, clumping of CNTs’ inner side of the agglomerations, CNT volume fraction and impact location on the responses of impact load, projectile displacement and plate deflection are analytically studied. These achievements illuminate how the influence of agglomeration size is very small on the impact response. Also, the influence of clumping of CNTs’ inner side of the agglomerations is significant, and as it increases, the displacement values and impact time increase, and the impact force decreases.

Originality/value

In this article, to avoid additional calculations, the parameters of the mass matrix and the stiffness coefficients are linearized to obtain the equations of motion of the impact on the circular plate.

Details

Multidiscipline Modeling in Materials and Structures, vol. 19 no. 5
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 24 July 2023

Mehdi Ranjbar-Roeintan

The purpose of this study is to investigate the strain rate effect on the problem of low-velocity impact (LVI) on a beam, including silicon nitride and stainless steel materials.

73

Abstract

Purpose

The purpose of this study is to investigate the strain rate effect on the problem of low-velocity impact (LVI) on a beam, including silicon nitride and stainless steel materials.

Design/methodology/approach

Based on the nonlinear Hertz impact mechanism, the energies related to the impactor and the beam are written, and motion equations are derived using the Lagrangian mechanics and Ritz method. The strain rate term is represented as a damping matrix in the equations of motion. In the issue of LVI on the silicon nitride and stainless steel beam, the effect of internal viscous damping coefficient in simply–simply and clamped–free boundary conditions are studied. Also, the influence of the volume fraction index in the range between zero and one and greater than one on the impact response is investigated.

Findings

The results make it clear that the strain rate parameter had little effect on the response in LVI. Also, an increase in the volume fraction index has led to a decrease in the contact force and an increase in the rebound velocity of the impactor.

Originality/value

The effect of strain rate on LVI is theoretically studied in this paper, while in most of the papers, this effect is investigated experimentally and numerically.

Details

World Journal of Engineering, vol. 21 no. 5
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 12 April 2023

Mehdi Ranjbar-Roeintan

The purpose of this article is to investigate the porosity-dependent impact study of a plate with Winkler–Pasternak elastic foundations reinforced with agglomerated carbon…

72

Abstract

Purpose

The purpose of this article is to investigate the porosity-dependent impact study of a plate with Winkler–Pasternak elastic foundations reinforced with agglomerated carbon nanotubes (CNTs).

Design/methodology/approach

Based on the first-order shear deformation plate theory, the strain energy related to elastic foundations is added to system strain energy. Using separation of variables and Lagrangian generalized equations, the nonlinear and time-dependent motion equations are extracted.

Findings

Verification examples are fulfilled to prove the precision and effectiveness of the presented model. The impact outputs illustrate the effects of various distribution of CNTs porosity functions along the plate thickness direction, Winkler–Pasternak elastic foundations and different boundary conditions on the Hertz contact law, the plate center displacement, impactor displacement and impactor velocity.

Originality/value

This paper investigates the effect of Winkler–Pasternak elastic foundations on the functionally graded porous plate reinforced with agglomerated CNTs under impact loading.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 8
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 3 October 2023

Mohammad Hadi Moradi and Mehdi Ranjbar-Roeintan

The purpose of this research is to extract the natural frequencies of a circular plate containing a central hole reinforced with boron nitride nanotubes (BNNTs) and containing…

47

Abstract

Purpose

The purpose of this research is to extract the natural frequencies of a circular plate containing a central hole reinforced with boron nitride nanotubes (BNNTs) and containing piezoelectric layers.

Design/methodology/approach

A unit cell shall be taken into account for the simulation of BNNT's volume fraction. A rectangular micromechanical model is used to obtain the mechanical properties of unit cell of piezoelectric fiber-reinforced composite (PFRC). The three-dimensional (3D) elasticity method is presented to provide the relationship between displacements and stresses. The one-dimensional differential quadrature method (1D-DQM) and the state-space methodology are combined to create the semi-analytical technique. The state-space approach is utilized to implement an analytical resolution in the thickness direction, and 1D-DQM is used to implement an approximation solution in the radial direction. The composite consists of a polyvinylidene fluoride (PVDF) matrix and BNNTs as reinforcement.

Findings

A study on the PFRC is carried, likewise, the coefficients of its properties are obtained using a micro-electromechanical model known as the rectangular model. To implement the DQM, the plate was radially divided into sample points, each with eight state variables. The boundary situation and DQM are used to discretize the state-space equations, and the top and bottom application surface conditions are used to determine the natural frequencies of the plate. The model's convergence is assessed. Additionally, the dimensionless frequency is compared to earlier works and ABAQUS simulation in order to validate the model. Finally, the effects of the thickness, lateral wavenumber, boundary conditions and BNNT volume fraction on the annular plate's free vibration are investigated. The important achievements are that increasing the volume fraction of BNNTs increases the natural frequency.

Originality/value

The micromechanical “XY rectangle” model in PFRC along with the three-dimensional elasticity model is used in this literature to assess how the piezoelectric capabilities of BNNTs affect the free vibration of polymer-based composite annular plates under various boundary conditions.

Details

International Journal of Structural Integrity, vol. 14 no. 6
Type: Research Article
ISSN: 1757-9864

Keywords

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