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Non-Newtonian fluid flow in an axisymmetric channel with porous wall

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Propulsion and Power Research 2013年第4期2卷 254-262页

作者： m.hosseini Z.Sheikholeslami D.D.Ganji Department of mechanical Engineering Islamic Azad UniversityQaemshahr BranchQaemshahrMazandaranIran Department of Civil Engineering University of MazandaranBabolsarIran Department of mechanical Engineering Babol University of TechnologyBabolIran

In the present article Optimal Homotopy Asymptotic method(OHAm)is used to obtain the solutions of momentum and heat transfer equations of non-Newtonian fluid flow in an axisymmetric channel with porous wall for turbine cooling *** method is used for validity of this analytical method and excellent agreement is observed between the solutions obtained from OHAm and numerical *** to this validity,effects of some other parameters are *** results show that Nusselt number increases with increase of Reynolds number,Prandtl number and power law index.

关键词： Non-Newtonian fluid Axisymmetric channel Porous media Optimal Homotopy Asymptotic method(OHAm) Heat transfer

Analytical investigation of laminar flow through expanding or contracting gaps with porous walls

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Propulsion and Power Research 2014年第4期3卷 222-229页

作者： m.Jafaryar F.Farkhadnia E.mohammadian m.hosseini A.m.Khazaee Department of mechanical Engineering Mazandaran Insitute of TechnologyBabol Iran Department of mechanical Engineering Mechanics GroupRamsar BranchIslamic Azad UniversityRcmsarIran Deparment of mechanical Engineering Islamic Azad UniversityQaemshahr BranchQaemshahrMazandaranIran Department of mechanical Engineering Babol University of TechnologyBabolIran

Laminar,isothermal,incompressible and viscous flow in a rectangular domain bounded by two moving porous walls,w hich enable the fuid to enter or exit during successive expansions or contractions is investigated analytically using optimal homotopy asymptotic method(OHAm).OHAm is a powerful method for solving nonlinear problems without depending to the small *** concept of this method is briefly introduced,and it's application for this problem is ***,the results are compared with numerical results and the validity of these methods is *** this verification,we analyze the effects of some physical applicable parameters to show the efficiency of OHAm for this type of *** results are presented to investigate the influence of the non-dimensional wall dilation rate(a)and pemeation Reynolds number(Re)on the velocity,normal pressure distribution and wall shear *** present problem for slowly expanding or contracting walls with weak permeability is a simple model for the transport of biological fuids through contracting or expanding vessels.

关键词： Optimal homotopy asymptotic method(OHAm) Viscous flow Permeation Reynolds number Non-dimensional wall dilation rate Laminar flow Permeable channel

碱性溶液中分子氧在多晶银上的多步还原(英文)

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催化学报 2010年第5期31卷 541-546页

作者： m.JAFARIAN F.GOBAL m.G.mAHJANI m.hosseini ALIABAD Department of Chemistry K.N.Toosi University of Technology Department of Chemistry Sharif University of Technology

Oxygen reduction on a polycrystalline silver electrode was studied by cyclic voltammetry and electrochemical impedance *** reaction occurred by a two-electron *** steps in the mechanism were observed in the cyclic voltammograms recorded with different scan *** intermediates formed in the steps were detected by electrochemical impedance spectroscopy.

关键词：银氧减小周期的 voltammetry 电气化学的阻抗光谱学

Soliton and other solutions to the (1+2)-dimensional chiral nonlinear Schrodinger equation

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Communications in Theoretical Physics 2020年第12期72卷 99-104页

作者： K hosseini m mirzazadeh Department of mathematics Rasht BranchIslamic Azad UniversityRashtIran Department of Engineering Sciences Faculty of Technology and EngineeringEast of GuilanUniversity of GuilanUniversity of GuilanP.C.44891-63157 Rudsar-VajargahIran

The(1+2)-dimensional chiral nonlinear Schr?dinger equation(2D-CNLSE)as a nonlinear evolution equation is considered and studied in a detailed *** this end,a complex transform is firstly adopted to arrive at the real and imaginary parts of the model,and then,the modified Jacobi elliptic expansion method is formally utilized to derive soliton and other solutions of the *** exact solutions presented in this paper can be classified as topological and nontopological solitons as well as Jacobi elliptic function solutions.

关键词： modified Jacobi elliptic expansion method (1+2)-dimensional chiral nonlinear Schrodinger equation topological and nontopological solitons Jacobi elliptic function solutions

Thermo-magnetic analysis of thick-walled spherical pressure vessels made of functionally graded materials

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Applied mathematics and mechanics(English Edition) 2019年第6期40卷 751-766页

作者： m. A. NEmATOLLAHI A. DINI m. hosseini Department of Biosystems Engineering College of AgricultureShiraz UniversityShiraz 71441-65186Iran Department of mechanical Engineering Ferdowsi University of MashhadMashhad 91775-1111Iran Department of mechanical Engineering Sirjan University of TechnologySirjan 78137-33385Iran

This study presents an analytical solution of thermal and mechanical displacements, strains, and stresses for a thick-walled rotating spherical pressure vessel made of functionally graded materials (FGms). The pressure vessel is subject to axisymmetric mechanical and thermal loadings within a uniform magnetic field. The material properties of the FGm are considered as the power-law distribution along the thickness. Navier’s equation, which is a second-order ordinary differential equation, is derived from the mechanical equilibrium equation with the consideration of the thermal stresses and the Lorentz force resulting from the magnetic field. The distributions of the displacement, strains, and stresses are determined by the exact solution to Navier’s equation. Numerical results clarify the influence of the thermal loading, magnetic field, non-homogeneity constant, internal pressure, and angular velocity on the magneto-thermo-elastic response of the functionally graded spherical vessel. It is observed that these parameters have remarkable effects on the distributions of radial displacement, radial and circumferential strains, and radial and circumferential stresses.

关键词： analytical solution magnetic field thermal loading rotating thick-walled spherical pressure vessel functionally graded material (FGm)

Static and dynamic responses of a microcantilever with a T-shaped tip mass to an electrostatic actuation

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Acta mechanica Sinica 2016年第6期32卷 1104-1122页

作者： B.Firouzi m.Zamanian S.A.A.hosseini Department of mechanical Engineering Faculty of Engineering Kharazmi University

In this study, nonlinear static and dynamic responses of a microcantilever with a T-shaped tip mass excited by electrostatic actuations are investigated. The electrostatic force is generated by applying an electric voltage between the horizontal part of T-shaped tip mass and an opposite electrode plate. The cantilever microbeam is modeled as an Euler-Bernoulli beam. The T-shaped tip mass is assumed to be a rigid body and the nonlinear effect of electrostatic force is considered. An equation of motion and its associated boundary conditions are derived by the aid of combining the Hamilton principle and Newton’s method. An exact solution is obtained for static deflection and mode shape of vibration around the static position. The differential equation of nonlinear vibration around the static position is discretized using the Galerkin method. The system mode shapes are used as its related comparison functions. The discretized equations are solved by the perturbation theory in the neighborhood of primary and subharmonic resonances. In addition, effects of mass inertia, mass moment of inertia as well as rotation of the T-shaped mass, which were ignored in previous works, are considered in the analysis. It is shown that by increasing the length of the horizontal part of the T-shaped mass, the amount of static deflection increases, natural frequency decreases and nonlinear shift of the resonance frequency increases. It is concluded that attaching an electrode plate with a T-shaped configuration to the end of the cantilever microbeam results in a configuration with larger pull-in voltage and smaller nonlinear shift of the resonance frequency compared to the configuration in which the electrode plate is directly attached to it.

关键词： mEmS Electrostatic Static deflection Natural frequency Pull-in voltage Perturbation theory T-shaped mass Primary and subharmonic resonances

Nonlinear beam formulation incorporating surface energy and size effect:application in nano-bridges

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Applied mathematics and mechanics(English Edition) 2016年第5期37卷 583-600页

作者： A.KOOCHI H.hosseini-TOUDESHKY m.ABADYAN Department of Aerospace Engineering Amirkabir University of TechnologyTehran 15875-4413Iran mechanical Engineering Group Shahrekord BranchIslamic Azad UniversityShahrekord ***Iran

A nonlinear beam formulation is presented based on the Gurtin-murdoch surface elasticity and the modified couple stress theory. The developed model theoretically takes into account coupled effects of the energy of surface layer and microstructures size- dependency. The mid-plane stretching of a beam is incorporated using von-Karman nonlinear strains. Hamilton＇s principle is used to determine the nonlinear governing equation of motion and the corresponding boundary conditions. As a case study, pull-in instability of an electromechanical nano-bridge structure is studied using the proposed formulation. The nonlinear governing equation is solved by the analytical reduced order method （ROm） as well as the numerical solution. Effects of various parameters including surface layer, size dependency, dispersion forces, and structural damping on the pull- in parameters of the nano-bridges are discussed. Comparison of the results with the literature reveals capability of the present model in demonstrating the impact of nano- scale phenomena on the pull-in threshold of the nano-bridges.

关键词： surface energy size effect nonlinear beam formulation electromechanicalnano-bridge pull-in instability

CFD modeling of a spouted bed with a porous draft tube

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Particuology 2010年第5期8卷 415-424页

作者： Salar Azizi Seyyed Hossein hosseini m.moraveji Goodarz Ahmadi Chemical Engineering Department Faculty of EngineeringArak University Department of Chemical Engineering Faculty of EngineeringIlam University Department of mechanical and Aeronautical Engineering Clarkson University

Spouted bed with a porous draft tube is used for drying of grains and chemical products and thermal disinfestations process. This work provides a computational fluid dynamics （CFD） simulation of binary mixtures of glass particles in a spouted bed with a porous draft tube. The simulation used the multi-fluid Eulerian-Eulerian approach based on kinetic theory of granular flows, incorporating a kinetic-frictional constitutive model for dense assemblies of particulate solids and Gidaspow＇s drag model for the interaction between gas and particles. Influences of solids mass fraction and inlet gas flow rate on pressure distribution, gas and particle velocities were studied. The modeling results were compared with the exper- imental work of Ishikura, Nagashima, and Ide （2003） for the flow condition along the axis of the spouted bed. Good agreement between the modeling results and experimental data was observed.

关键词： Spouted bedPorous dra tubeHydrodynamicsKinetictheoryCFD

Application of fuzzy logic for determining of coal mine mechanization

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Journal of Coal Science & Engineering(China) 2012年第3期18卷 225-231页

作者： hosseini S AA ATAEI m.hosseini S m AKHYANI m Department of mining Shahrood BranchIslamic Azad UniversityShahroodIran Faculty of mining Petroleum and GeophysicsShahrood University of TechnologyShahroodIran

The fundamental task of mining engineers is to produce more coal at a given level of labour input and material costs, for optimum quality and maximum efficiency. To achieve these goals, it is necessary to automate and mechanize mining operations. mechanization is an objective that can result in significant cost reduction and higher levels of profitability for underground mines. To analyze the potential of mechanization, some important factors such as seam inclination and thickness, geological disturbances, seam floor conditions and roof conditions should be considered. In this study we have used fuzzy logic, membership functions and created fuzzy rule-based methods and considered the ultimate objective： mechanization of mining. As a case study, the mechanization of the Tazare coal seams in Shahroud area of Iran was investigated. The results show a low potential for mechanization in most of the Tazare coal seams.

关键词： fuzzy logic mechanization coal seams productivity fuzzytech software