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Chinese Physics C 2017年第6期41卷 69-74页

作者： S. S. hosseini h. hassanabadi Physics Department Shahrood University of Technology Shahrood Iran

We consider the systematics of α-decay half-lives of super-heavy nuclei versus the decay energy and the total α-kinetic energy. We calculate the half-lives using the experimental Qα values. The computed half-lives are compared with the experimental data and with existing empirical estimates and are found to be in good agreement. Also, we obtain α-preformation factors from the ratio between theoretical and experimental results for some super- heavy nuclei and evaluate the standard deviation. The results indicate the acceptability of the approach.

关键词： alpha decay super heavy nuclei (ShN) half-life preformation factor

CFD-DEM simulation of a pseudo-two-dimensional spouted bed comprising coarse particles

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Particuology 2019年第2期17卷 171-180页

作者： B. Mahmoodi S.h. hosseini G. Ahmadi llam Gas Treating Company llam Iran Department of Chemical Engineering llam University llam 69315-516 Iran Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

In the present study, computational fluid dynamics (CFD) and the discrete element method (DEM) are used in conjunction with the Eulerian-Lagrangian method to simulate a pseudo-two-dimensional spouted bed comprising coarse 6-mm particles. The open-source OpenFOAM code is used to solve the governing equations. The predicted vertical particle velocity along the bed axis, particle velocity profiles in the radial directi on, power spectral den sity, time-averaged particle velocity vectors, bed pressure drop, and solid flow pattern are evaluated and compared with existing experimental data. Good agreement is found between the CFD-DEM results and the measured data. It is also shown that the present CFD-DEM model accurately predicts the particle flow pattern throughout the bed. It is found that the drag force, solid stresses, and gravity play important roles in the CFD-DEM simulation of a spouted bed comprising coarse particles.

关键词： CFD-DEM Pseudo-2D spouted bed hydrodynamics Coarse particles

Reproducing fling-step and forward directivity at near source site using of multi-objective particle swarm optimization and multi taper

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Earthquake Engineering and Engineering Vibration 2013年第4期12卷 529-540页

作者： A.Nicknam A.hosseini h.hamidi Jamnani M.A.Barkhordari School of Civil Engineering Iran University of Science & Technology

This paper presents a technique to reproduce compatible seismogran3s involving permanent displacen3ent effects at sites close to the fault source. A multi-objective evolutionary algorithm is used to minimize the differences between the response spectra and multi-tapered power spectral delsilies corresponding to the recorded and simulated wavelbrms. The multi-taper method is used to reduce the spectral leakage that is inherent in the Fourier rams formed form ofwavelbrms, ieading to a reduction of variance in power spectral amplitudes, thus permitting the calibration of the two sets of data. The technique is implemented using the 1998-Fandoqa （lran） earthquake data and the results are compared with the actual observed data. Additionally, a comparison is made with a SAR interfcrometry study leading to fair agreement with the reported dislocation along the main fault. The simulation procedure and results are discussed and assessed concluding that, although the technique may be associated with uncertainties, it can still be used to reproduce wavelbnns at near source sites that include permanent dislocation, and can be used for seismic pertbrmance evaluation of structures in the region under study.

关键词： near-fault simulation fling step directivity multi-taper multi-objective algorithm MO-PSO

Surface and thermal effects on vibration of embedded alumina nanobeams based on novel Timoshenko beam model

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Applied Mathematics and Mechanics(English Edition) 2014年第7期35卷 875-886页

作者： B.AMIRIAN R.hosseini-ARA h.MOOSAVI Department of Mechanical Engineering Isfahan University of TechnologyIsfahan 84156-83111 Iran Department of Mechanical Engineering Payame Noor University Tehran 19395-3697 Iran

This paper deals with the free vibration analysis of circular alumina （Al2O3） nanobeams in the presence of surface and thermal effects resting on a Pasternak foun- dation. The system of motion equations is derived using hamilton＇s principle under the assumptions of the classical Timoshenko beam theory. The effects of the transverse shear deformation and rotary inertia are also considered within the framework of the mentioned theory. The separation of variables approach is employed to discretize the governing equa- tions which are then solved by an analytical method to obtain the natural frequencies of the alumina nanobeams. The results show that the surface effects lead to an increase in the natural frequency of nanobeams as compared with the classical Timoshenko beam model. In addition, for nanobeams with large diameters, the surface effects may increase the natural frequencies by increasing the thermal effects. Moreover, with regard to the Pasternak elastic foundation, the natural frequencies are increased slightly. The results of the present model are compared with the literature, showing that the present model can capture correctly the surface effects in thermal vibration of nanobeams.

关键词： surface effect thermal environment alumina nanobeam Pasternak foun-dation Timoshenko beam model

Cu-(B4C)p metal matrix composites processed by accumulative rollbonding

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Progress in Natural Science:Materials International 2016年第6期26卷 613-620页

作者： S.Mansourzadeh M.hosseini E.Salahinejad A.h.Yaghtin Department of Materials Science and Engineering College of Chemical and Metallurgical EngineeringShiraz BranchIslamic Azad University Department of Materials Science and Engineering School of EngineeringShiraz University Faculty of Materials Science and Engineering K.N.Toosi University of Technology

In this study, Cu/B4C metal matrix composites were prepared by accumulative roll-bonding(ARB). The microstructure of the processed samples was characterized by TEM, SEM and optical microscopy. The microhardness, uniaxial tensile and four-point probe tests were carried out to evaluate the mechanical properties and electrical resistivity of the ARBed monolithic and composite samples. The results showed that the reinforcement distribution was improved by increasing ARB cycles, which was quantitatively confirmed by some models. Based on TEM observations, the formation of an ultrafine grained structure in the composite matrix was also approved. It was shown that with increasing ARB cycles, the microhardness and tensile strength of the monolithic Cu samples were enhanced up to the 3rd cycle and then saturated, but the microhardness and tensile strength of the composites showed an increasing trend to the last cycle. Apart from a substantial improvement in the mechanical properties of the Cu/B4C composites, a minor decrement in electrical conductivity was detected after six ARB cycles.

关键词： Electron microscopy Mechanical characterization Composites

Dirac oscillator in noncommutative space

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Chinese Physics C 2014年第6期38卷 23-29页

作者： h.hassanabadi S.S.hosseini S.Zarrinkamar Physics Department Shahrood University Shahrood Iran P. O. Box: ***-316 Shahrood Iran Department of Basic Sciences Garmsar Branch Islamic Azad University Garmsar Iran

We study the Dirac oscillator problem in the presence of the Aharonov-Bohm effect with the harmonic potential in commutative and noncommutative spaces in S-= V and S =-V symmetry limits. We calculate exact energy levels and the corresponding eigenfunctions by the Nikiforov-Uvarov （NU） method and report the impact of the spin and the magnetic flux on the problem. helpful numerical data is included.

关键词： Dirac oscillator Aharonov-Bohm effect harmonic potential noncommutative space Nikiforov-Uvarov(NU) method

Klein Gordon Oscillators in Commutative and Noncommutative Phase Space with Psudoharmonic Potential in the Presence and Absence Magnetic Field

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Communications in Theoretical Physics 2013年第7期60卷 9-18页

作者： h. hassanabadi S.S. hosseini Z. Molaee Physics Department Shahrood University of Technology Physics Department Semnan University

We study the Klein-Gordon oscillator in commutative, noncommutative space, and phase space with psudoharmonic potential under magnetic field hence the other choice is studying the Klein-Gordon equation oscillator in the absence of magnetic field. In this work, we obtain energy spectrum and wave function in different situations by NU method so we show our results in tables.

关键词：空间磁场振荡器相空间 Klein-Gordon方程克莱因可交换非交换波函数

Comparative analysis of different static mixers performance by CFD technique:An innovative mixer

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Chinese Journal of Chemical Engineering 2020年第3期28卷 672-684页

作者： M.M.haddadi S.h.hosseini D.Rashtchian Martin Olazar Chemical and Petroleum Engineering Department Sharif University of TechnologyTehranIran Department of Chemical Engineering.Ilam University llam 69315-516Iran Department of Chemical Engineering University of the Basque Country(UPV/EHU)Sarriena s/nLeioaSpain

The flow and mixing behavior of two miscible liquids has been studied in an innovative static mixer by using CFD,with Reynolds numbers ranging from 20 to *** performance of the new mixer is compared with those of Kenics,SMX,and Komax static *** pressure drop ratio(Z-factor),coefficient of variation(CoV),and extensional efficiency(α)features have been used to evaluate power consumption,distributive mixing,and dispersive mixing performances,respectively,in all *** model is firstly validated based on experimental data measured for the pressure drop ratio and the coefficient of *** results are consistent with measured data and those obtained by available correlations in the *** new mixer shows a superior mixing performance compared to the other mixers.

关键词： CFD New static mixer Coefficient of variation Pressure drop ratio

CFD modeling of immiscible liquids turbulent dispersion in Kenics static mixers: Focusing on droplet behavior

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Chinese Journal of Chemical Engineering 2020年第2期28卷 348-361页

作者： M.M.haddadi S.h.hosseini D.Rashtchian G.Ahmadi Chemical and Petroleum Engineering Department Sharif University of TechnologyTehranIran Department of Chemical Engineering Ilam UniversityIlam 69315–516Iran Department of Mechanical and Aeronautical Engineering Clarkson UniversityPotsdamNY 13699-5725USA

The present study is concerned with the computational fluid dynamics(CFD)simulation of turbulent dispersion of immiscible liquids,namely,water–silicone oil and water–benzene through Kenics static mixers using the Eulerian–Eulerian and Eulerian–Lagrangian approaches of the ANSYS Fluent 16.0 *** study the droplet size distribution(DSD),the Eulerian formulation incorporating a population balance model(PBM)was *** the Eulerian–Lagrangian approach,a discrete phase model(DPM)in conjunction with the Eulerian approach for continuous phase simulation was used to predict the residence time distribution(RTD)of *** both approaches,a shear stress transport(SST)k-ωturbulence model was *** validation purposes,the simulated results were compared with the experimental data and theoretical values for the Fanning friction factor,Sauter mean diameter and the mean residence *** reliability of the computational model was further assessed by comparing the results with the available empirical correlations for Fanning friction factor and Sauter mean *** addition,the influence of important geometrical and operational parameters,including the number of mixing elements and Weber number,was *** was found that the proposed models are capable of predicting the performance of the Kenics static mixer reasonably well.

关键词： CFD Liquid–liquid dispersion Kenics static mixer Eulerian–Eulerian approach Eulerian–Lagrangian approach