Fa
  • Ph.D. (1990)

    Mechanical Engineering - Solid Design

    , Manchester, England

  • M.Sc. (1986)

    Mechanical Engineering - Solid Design

    , Manchester, England

  • B.Sc. (1979)

    mechanical engineering

    , Tabriz University,

  • Analysis and design of thin-walled structures and pressure vessels
  • Stress analysis

    Contact

    Curriculum Vitae (CV)

    On the free vibrations of joined grid-stiffened composite conical-cylindrical shells

    M Zarei, GH Rahimi, M Hemmatnezhad
    Journal PaperThin-Walled Structures , Volume 161 , 2021 April 1, {Pages 107465 }

    Abstract

    The present study aims to investigate the vibrational characteristics of joined stiffened conical-cylindrical composite shells using experimental, numerical and analytical techniques. The stiffness contribution of the shells and helical stiffeners have been superimposed by means of a smeared approach in order to calculate the total stiffness coefficients of the whole structure. The governing equations have been derived according to Donnell’s shallow thin shell theory and then solved using power series technique. Applying boundary conditions along with continuity conditions at the interface section of the shell segments, the natural frequencies and mode shapes of the grid-stiffened joined conical-cylindrical shells are obtained through an

    A meshless collocation method based on radial basis functions for free and forced vibration analysis of functionally graded plates using FSDT

    Shahram Hosseini, Gholamhossein Rahimi, Yavar Anani
    Journal PaperEngineering Analysis with Boundary Elements , Volume 125 , 2021 April 1, {Pages 168-177 }

    Abstract

    The current study presents a meshless collocation method based on radial basis functions (MC-RBF) to analyze the free and forced vibration of functionally graded plates. We used the first-order shear deformation plate theory for the displacements and strains. The governing equations are discretized via the MC-RBF method to obtain the natural frequencies. We suggested a new algorithm (modified LOOCV) to acquire the shape parameters of the radial basis function in the free and forced vibration problems. The discretized equations are converted to reduced equations via the proposed transformation matrix. The run-time of this method is significantly lower than the other methods. In particular, the accuracy of the proposed algorithm is acceptable

    Nonlinear Bending Analysis of Hyperelastic Plates Using FSDT and Meshless Collocation Method Based on Radial Basis Function

    Shahram Hosseini, Gholamhossein Rahimi
    Journal PaperInternational Journal of Applied Mechanics , 2021 February 16, {Pages }

    Abstract

    The current paper investigates the nonlinear bending analysis of a hyperelastic plate via neo-Hookean strain energy function. The first-order shear deformation plate theory is used for the formulation of the field variables. Also, nonlinear Lagrangian strains are considered via the right Cauchy-Green tensor. The governing equations and nonlinear boundary conditions are derived using Euler-Lagrange relations. The meshless collocation method based on radial basis function is used to discretize the governing equations of the hyperelastic plate. Square and circular plates are studied to evaluate the accuracy of the meshless collocation method based on thin-plate spline (TPS) and multiquadric (MQ) and logarithmic thin-plate spline (LTPS) radial

    Global buckling load calculation of the of sandwich conical shells with lattice cores subjected to axial compression loading using a novel smeared method

    Gholamhossein Rahimi, Mehdi Zarei
    Journal PaperJournal of Science and Technology of Composites , 2021 January 29, {Pages }

    Abstract

    In the present paper, an analytical model was presented according to a novel smeared stiffener approach in order to predict the global buckling load of composite sandwich conical shells with lattice core subjected to axial compression loading. The sandwich panel was made up of two skins and a lattice core. A smeared method was developed to approximate the lattice core with an equivalent composite shell. First, using the forces and moments analyses of a unit cell, the stiffness contribution due to the lattice were determined and then superimposed with those of the inner and outer skins in order to obtain the stiffness parameters of the whole panel. The governing equations were extracted according to the classical shell theory of Donnell type

    The Role of Earthworms (Eisenia fetida) on the Bioavailability of Contaminated Soil with Heavy Metals

    Gh Rahimi, F Noroozi Goldareh
    Journal PaperJWSS-Isfahan University of Technology , Volume 24 , Issue 4, 2021 February 10, {Pages 211-222 }

    Abstract

    Earthworms are soil organisms commonly used in environmental studies and biological toxicology. Therefore, the present study aimed to investigate the role of Eisenia Fetida earthworms on the bioavailability of zinc and copper in the contaminated soils. This study was carried out on a contaminated soil sampled from the Ahangaran mine 26 kilometers far from the city of Malair and its surrounding areas. In this experiment, 12 earthworms with the average weight of 0.3-0.6 g were selected for each soil sample. The worms were exposed to a metal contaminated soil for 42 days. After the test time, Zinc (Zn) and Cupper (Cu) concentrations were measured in different fractions of the soil. The results showed that cow manure, carrot pulp and vermicompo

    On the buckling resistance of grid-stiffened composite conical shells under compression

    M Zarei, GH Rahimi, M Hemmatnezhad
    Journal PaperEngineering Structures , Volume 237 , 2021 June 15, {Pages 112213 }

    Abstract

    In this paper, an analytical approach has been employed to investigate the global buckling behavior of grid-stiffened composite conical shells with cross stiffeners, on the basis of the first-order shear deformation theory (FSDT). First, the equivalent stiffness parameters of the stiffening structure have been derived through smearing the forces and moments on a typical unit cell taking the shear effects into consideration. Then, superimposing this stiffness contribution with those of the skin, the equivalent stiffness associated with the whole structure is determined. The power series method has been used to solve the equations governing the global buckling of the grid-stiffened composite conical shells. The obtained analytical results hav

    The Influence of Variable Shell Thickness On the Vibrational Behavior of Composite Sandwich Conical Shells with Geodesic Lattice Cores

    M Zarei, GH Rahimi, M Hemmatnezhad
    Journal Paper , , {Pages }

    Abstract

    Buckling characteristics of sandwich conical shells with variable skin thickness

    M Zarei, GH Rahimi
    Journal Paper , , {Pages }

    Abstract

    Nonlinear analysis of hyperelastic plates using first-order shear deformation plate theory and a meshless method

    S Hosseini, GH Rahimi, Y Anani
    Journal Paper , , {Pages }

    Abstract

    Nonlinear bending analysis of multi-layer hyperelastic silicon-rubber plates using meshless based on radial basis functions

    S Hosseini, G Rahimi
    Journal Paper , , {Pages }

    Abstract

    A meshless collocation method on nonlinear analysis of functionally graded hyperelastic plates using radial basis function

    S Hosseini, G Rahimi, D Shahgholian‐Ghahfarokhi
    Journal Paper , , {Pages }

    Abstract

    Free vibrational characteristics of grid-stiffened truncated composite conical shells

    M Zarei, GH Rahimi, M Hemmatnezhad
    Journal PaperAerospace Science and Technology , 2020 January 22, {Pages 105717 }

    Abstract

    In this paper, the free vibrational behavior of composite conical shells stiffened by bevel stiffeners is investigated using experimental, analytical and numerical techniques. The smeared method is employed to superimpose the stiffness contribution of the stiffeners with those of shell in order to obtain the equivalent stiffness parameters of the whole structure. Due to the specific geometry of the conical shell, the whole structure is converted to a conical shell with variable stiffness and thickness. The stiffeners are considered to be of beam-type which support shear load and bending moments in addition to the axial loads. The geodesic path is applied to the stiffeners. The governing equations have been derived based on the first-order s

    Integrity assessment of functionally graded pipe produced by centrifugal casting subjected to internal pressure: experimental investigation

    Aref Mehditabar, Gholam H Rahimi, Seyed Ebrahim Vahdat
    Journal PaperArchive of Applied Mechanics , 2020 March 21, {Pages 14-Jan }

    Abstract

    Precise prediction of collapse pressure is a key role in structural integrity assessment of piping systems. The present study uses an functionally graded (FG) pipe fabricated through horizontal centrifugal casting technique to empirically investigate its mechanical responses under hydrostatic pressure test. The evolutions of deformations correspond to the external surface of the FG pipe in the axial and hoop directions recorded by strain gauges and data acquisition during pressurization are outlined. Moreover, finite element simulation using user subroutine USDFLD implemented into the commercial software ABAQUS is applied to numerically study the tested FG pipe under similar environmental and loading conditions used in the experimental proc

    Effect of Heat Treatment on the Characterizations of Functionally Graded Al/Al 2 Cu Fabricated by Horizontal Centrifugal Casting

    Aref Mehditabar, Gholam H Rahimi, Mariusz Krol, Seyed Ebrahim Vahdat
    Journal PaperInternational Journal of Metalcasting , 2020 January 6, {Pages 15-Jan }

    Abstract

    In the present paper, in situ centrifugal casting as an advanced material processing method is proposed to fabricate Al–26 wt% Cu–7wt% Si FG pipe with the density of 3.5 g/cm 3 and with the wear resistance of 1.85064? 10− 16 m 3/mN. The casting mould is preheated to approximately 200 C to avoid chilling effects, segregation, porosity and compensation of the shrinkage of the alloy during the casting. Variations of the Al 2 Cu-based content are investigated by the field emission scanning electron microscopy (FESEM) in conjunction with image analyser software (MATLAB code). The microstructure results show that the Al 2 Cu content smoothly decreases from the outer layer containing 44.4 vol% to inner layer containing 37.8 vol% due to the d

    Cyclic elastoplastic responses of thick-walled FG pipe behaves as a power law function considering damage evolution

    A Mehditabar, GH Rahimi
    Journal PaperMechanics Based Design of Structures and Machines , 2020 May 19, {Pages 19-Jan }

    Abstract

    The present article is devoted to the cyclic responses of functionally graded (FG) pipe incorporating continuum damage mechanics parameters under thermomechanical loadings. The thermal, mechanical, the coefficients of Chaboche nonlinear kinematic hardening model, and damage parameters are considered to be varied continuously in the radial direction with power-law function, instead of being constant. The implicit backward Euler integration scheme along with return mapping algorithm implemented within user-defined material subroutine (UMAT) in the ABAQUS finite element (FE) software obtain the numerical solutions. The accuracy of the numerical algorithm in predicting the cyclic responses of metals is validated through comparing with experimen

    Experimental buckling analysis of composite sandwich plates with lozenge core using the vibration correlation technique (VCT)

    Milad Aghaei-Ruzbahani, Davoud Shahgholian-Ghahfarokhi, GH Rahimi
    Journal PaperModares Mechanical Engineering , Volume 20 , Issue 5, 2020 May 10, {Pages 0-0 }

    Abstract

    This open-access journal is published under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License which permits Share (copy and redistribute the material in any medium or format) and Adapt (remix, transform, and build upon the material) under the Attribution-NonCommercial terms.

    Investigation of debonding growth between composite skins and corrugated foam-composite core in sandwich panels under bending loading

    Hossein Malekinejad Bahabadi, Amin Farrokhabadi, Gholam Hossein Rahimi
    Journal PaperEngineering Fracture Mechanics , 2020 March 10, {Pages 106987 }

    Abstract

    This study investigates experimentally and numerically the resistance to separation between composite skins and different complex geometries of the corrugated core filled with PVC foam. To this purpose, three different geometries including simple foam core without any corrugated composite, longitudinal trapezoid, and square cores are considered and manufactured as waved (corrugated) composite core. In each specimen, an artificial pre-crack is located between the skin and core and then the effect of the skin's thickness and the core shaped on the debonding growth are examined for the first time. Three-point bending tests are carried out using ENS (End Notch Shear) fixture. Furthermore, the nonlinear response due to separation initiation and

    A sensitivity study of the free vibration of composite sandwich cylindrical shells with grid cores

    Davoud Shahgholian-Ghahfarokhi, Gholamhossein Rahimi
    Journal PaperIranian Journal of Science and Technology, Transactions of Mechanical Engineering , Volume 44 , Issue 1, 2020 March , {Pages 149-162 }

    Abstract

    In this paper, a sensitivity study of the free vibration of composite sandwich cylindrical shells with grid cores is performed by using Taguchi method. Six parameters such as stiffeners’ number, layers’ number of inner and outer skins, stiffener thickness, outer and inner skin thicknesses, boundary condition and outer and inner skin ply stacking sequences are considered. To do so, five levels are selected for each parameter. The orthogonal array is selected while longitudinal, circumferential and orthogonal grid cores are considered for the core configuration. A detailed finite element analysis is also used to calculate the natural frequency of composite sandwich cylindrical shells with grid cores. Finally, the effects of the paramet

    Cytoprotective effects of antioxidant supplementation on mesenchymal stem cell therapy

    Mohammad Panahi, Bahareh Rahimi, Golbarg Rahimi, Teck Yew Low, Neda Saraygord‐Afshari, Effat Alizadeh
    Journal PaperJournal of Cellular Physiology , 2020 April 2, {Pages }

    Abstract

    Mesenchymal stem cells (MSCs) are earmarked as perfect candidates?for cell therapy and tissue engineering due to their capacity to differentiate into different cell types. However, their potential for application in regenerative medicine declines when the levels of the reactive oxygen and nitrogen species (RONS) increase from the physiological levels, a phenomenon which is at least inevitable in ex vivo cultures and air‐exposed damaged tissues. Increased levels of RONS can alter the patterns of osteogenic and adipogenic differentiation and inhibit proliferation, as well. Besides, oxidative stress enhances senescence and cell death, thus lowering the success rates of the MSC engraftment. Hence, in this review, we have selected some repres

    Stability analysis of a mixed convection flow over a moving plate with non-uniform thickness

    SV Subhashini, S Lenin Sindhu, K Vajravelu
    Journal PaperArchive of Applied Mechanics , 2020 July 1, {Pages 11-Jan }

    Abstract

    This paper focuses on the effects of the boundary wall thickness and the velocity power index parameters on a steady 2D mixed convection flow along a vertical semi-infinite moving plate with non-uniform thickness. The effects of diffusion on the velocity, temperature and concentration fields with power-law temperature and concentration distributions at the plate surface are also analyzed. A shooting technique is adopted to obtain dual solutions for the system of nonlinear coupled ordinary differential equations. The significant impacts on the boundary layer development along the boundary surface have been noticed due to the non-flatness of the moving surface. It is noted that the velocity, temperature and concentration profiles admit dual

    Current Teaching

    • Ph.D.

      Theory of Plate and Shells

    Teaching History

    • MS.c.

      Continuum Mechanics I

    • 2019
      Ahmadi, Mohammad
      Numerical and experimental study of buckling load of sandwich plates with composite surfaces and corrugated core by VCT
    • 2019
      Abaspour, Ali
    • 2019
      Aghilidehnavi, Amirhossein
    • 2019
      NIKSIRAT, MIRMEYSAM
    • 2020
      Alizadeh bi panah, Ehsan
    • 2018
      Heidari, Moslem
      investigating energy harvesting from horizental and vertical movements of waves by using NES concept
    • 2018
      Dadashi, Amin
    • 2019
      HAJBAGHERI FOROUSHANI, MOHAMMAD HASSAN
    • 2020
      MemarMaher, Behnam

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