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Numerical simulation of a falling droplet surrounding by air under electric field using VOF method:A CFD study

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Chinese Journal of Chemical Engineering 2020年第12期28卷 2977-2984页

作者： Mirollah hosseini Hossein Arasteh Hamid Hassanzadeh Afrouzi Davood Toghraie Department of Mechanical Engineering Qaemshahr BranchIslamic Azad UniversityQaemshahrMazandaranIran Department of Mechanical Engineering Isfahan University of TechnologyIsfahanIran Babol Noshirvani University of Technology BabolIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

This is a numerical study of a falling droplet surrounding by air under the electric field modeled with finite volume method by means of *** VOF method has been employed to model the two-phase flow of the present *** capillary numbers are investigated to analyze the effects of electric field intensity on the falling droplet ***,the effects of electric potential on the heat transfer coefficient have been *** obtained results showed that by applying the electric field at a capillary number of 0.2 the droplet tends to retain its primitive shape as time goes by,with a subtle deformation to an oblate *** the electric field to a capillary number of 0.8 droplet deformation is almost insignificantwith time progressing;however,further enhancement in capillary number to 2 causes the droplet to deform as a prolate shape and higher values of this number intensify the prolate form deformation of the droplet and result in pinch-off ***,it is showed that as the electric potential augments the heat transfer coefficient increases in which for electric potential values higher than 2400 V the heat transfer coefficient enhances significantly.

关键词： Two-phase flow VOF method Falling droplet Electric field CFD study

Numerical Simulation of the Mechanical Properties of Sintered and Bonded Perforated Hollow Sphere Structures (PHSS)

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Journal of Materials Science & Technology 2010年第8期26卷 730-736页

作者： Andreas chsner Seyed Mohammad Hossein hosseini Markus Merkel Department of Applied Mechanics Technical University of Malaysia Centre for Mass and Mechanical Transport in Engineering Materials The University of Newcastle CallaghanNewSouth Wales 2308Australia Department of Mechanical Engineering University of Applied Sciences Aalen

This paper investigated the uniaxial mechanical properties of a new type of hollow sphere structures. For this new type, the sphere shell was perforated by several holes in order to open the inner sphere volume and surface. The mechanical properties, i.e. elastic properties and initial yield stress of perforated hollow sphere structures （PHSS） in a primitive cubic arrangement were numerically evaluated for different hole diameters and different joining techniques of the hollow spheres. The results are compared to classical configurations without perforation.

关键词： Mechanical properties Cellular material Porous structure Finite element method

Effect of Oxidizing Atmosphere on the Surface of Titanium Dental Implant Material

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Journal of Bionic Engineering 2019年第6期16卷 1052-1060页

作者： Mohammad Khodaei Akram Alizadeh Hamid Reza Madaah hosseini Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan 87717-65651Iran Department of Tissue Engineering School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekord 88157-13471Iran Department of Materials Science and Engineering Sharif University of TechnologyTehran 14588-89694Iran

Direct oxidation is a simple and effective method for titanium surface *** this research,a titanium sample was directly oxidized at the high temperature in two different atmospheres,air and pure oxygen,to obtain better atmosphere for titanium surface *** results of the Raman spectroscopy indicated that in both atmospheres,the rutile bioactive phase(TiO2)has been formed on the titanium *** results of X-ray diffraction(XRD)also revealed that the surface of oxygen-treated sample was composed of the rutile phase and titanium monoxide(TiO),while at the surface of the air-treated sample,the rutile phase and titanium dioxide had been ***,the results of Field Emission Scanning Electron Microscopy(FE-SEM)showed that by the surface treatment of titanium in both atmospheres,some micro-features including cracks thinner than 30 nm were formed on the *** of more apatite forming ability and fewer water contact angle and more L-929 cell attachment of the air-treated titanium,it seemed that air,in comparison to the pure oxygen,is more promising atmosphere for the direct oxidation of titanium and improving its biofunctionalization.

关键词： titanium implant surface treatment direct oxidation anatase rutile biomedical-materials

A generalized set of correlations for plus fraction characterization

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Petroleum Science 2012年第3期9卷 370-378页

作者： JAMIALAHMADI Mohamad ZANGENEH Hossein hosseini Seyed Sajad Petroleum Engineering Department Petroleum University of Technology Chemical & Petroleum Engineering Department Sharif University of Technology

The importance of accurate determination of the critical properties of plus fractions in prediction of phase behaviour of hydrocarbon mixtures by equations of state is well known in the petroleum industry. It has been stated in various papers （Elsharkawy, 2001） that using the plus fraction as a single group in equation of state calculations reduces the accuracy of the results. However in this work it has been shown that using the proper values of critical temperature and pressure for the plus fraction group can estimate the properties of hydrocarbon mixtures, and they are accurate enough to be used in reservoir engineering and enhanced oil recovery calculations. In this paper, a new method is proposed for calculating the critical properties of plus fractions of petroleum fluids. One can use this method either in predicting critical pressure and temperature of single carbon numbers （SCNs） after the splitting process or in predicting critical pressure and temperature of the plus fraction as a single group. A comparison study is performed against Riazi-Daubert correlation （Riazi and Daubert, 1987） and Sancet correlations （Sancet, 2007） for 25 oil samples taken from 14 fields from southwest Iran. The results indicate the superiority of the proposed method to the Riazi-Daubert and Sancet correlations.

关键词： Plus fraction critical properties correlation single carbon number bubble point calculations

Modeling of D-STATCOM in distribution systems load flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1532-1542页

作者： hosseini Mehdi SHAYANFAR Heidar Ali FOTUHI-FIRUZABAD Mahmud Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Technical Engineering of Babol University of Mazandaran Shariati Ave. 47144 P. O. Box 484 Babol Iran Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Department of Electrical Engineering Sharif University of Technology Azadi Ave. 11365-9363 Tehran Iran

This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.

关键词： Distribution system D-STATCOM Voltage compensation Load flow

Experimental Investigation and Semi-Active Control Design of A Magnetorheological Engine Mount

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Sound & Vibration 2019年第6期53卷 297-308页

作者： Seyed Salman hosseini Javad Marzbanrad School of Automotive Engineering Iran University of Science and TechnologyTehranIran Faculty at School of Automotive Engineering Iran University of Science and TechnologyTehranIran

In this paper;the dynamic characteristics of a semi-active magnetorheological fluid(MRF)engine mount are *** do so,the performance of the MRF engine mount is experimentally examined in higher frequencies(50~170 Hz)and the various amplitudes(0.01~0.2 mm).In such an examination,an MRF engine mount along with its magnetically biased is fabricated and successfully *** addition,the natural frequencies of the system are obtained by standard hammer modal *** modelling the behavior of the system,a mass-spring-damper model with tuned PID coefficients based on Pessen integral of absolute error method is *** parameters of such a model including mass,damping ratio,and stiffness are identified with the help of experimental modal tests and the recursive least square method(RLS).It is shown that using PID controller leads to reducing the vibration transmissibility in the resonance frequency(=93.45 Hz)with respect to the typical passive engine mount by a factor of 58%.The average of the vibration transmissibility decreasing is also 43%within frequency bandwidth(50~170 Hz).

关键词： Semi-active engine mount PID controller experimental data least square method magnetorheological fluid

Comparison of Antioxidant Status between Pilots and Non-flight Staff of the Army Force: Pilots May Need More Vitamin C

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Biomedical and Environmental Sciences 2014年第5期27卷 371-377页

作者： Elham Amiri Taleghani Gity Sotoudeh Kazem Amini mahboubeh Heidari Araghi Babak Mohammadi Haleh Sadrzadeh Yeganeh Department of Community Nutrition School of Nutritional Sciences and Dietetics Tehran University of Medical Sciences Department of Aerospace Medicine School of Aerospace Medicine Army University of Medical Sciences Department of Nutrition School of Health Yazd University of Medical Sciences

Objective To compare the blood antioxidant levels and dietary antioxidant intakes between pilots and non-flight staff of the Army Force in The Islamic Republic of Iran. Methods Thirty-seven helicopter pilots and 40 non-flight staff were included in this study. Their general characteristics were recorded and their weight, height, and waist circumference were measured. Their daily intake of energy and nutrients including antioxidants was assessed using a semi-quantitative food frequency questionnaire. Serum levels of total antioxidant capacity （TAC）, malondialdehyde （MDA）, and glutathione reductase （GR）, glutathione peroxidase （GPx）, superoxide dismutase （SOD）, and catalase （CAT） in red blood cells were also measured. Results The median erythrocytes SOD, serum MDA level and the mean serum level of TAC and erythrocytes GPx were significantly higher in pilots than in non-flight staff. The median vitamin C intake was significantly lower in pilots than in non-flight staff. The serum MDA levels were similar in non-flight staff and pilots when their vitamin C intake was 〈168 mg and significantly lower in non-flight staff than in pilots when their vitamin C intake was 〉168 mg. Conclusion The serum MDA level is lower in non-flight staff than in pilots when their vitamin C intake level is high, indicating that pilots need more vitamin C than non-flight staff.

关键词： Antioxidant status Pilots Army force

Land-use change and carbon stocks: A case study, Noor County, Iran

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Journal of Forestry Research 2013年第3期24卷 461-469页

作者： Niloufar Haghdoost Moslem Akbarinia Seyed Mohsen hosseini Department of Forestry Faculty of Natural Resources Tarbiat Modares UniversityNoor Mazandaran Iran. Postal code: 46417-76489 Department of Forestry Faculty of Natural Resources Tarbiat Modares UniversityNoor Mazandaran Iran

Land-use changes and land cover strongly influence carbon stock and distribution within ecosystems. Changing the land-use from natural forest to other land-uses has been more rapid in the past few decades than at any time in Iran＇s history. In this study, we investigated the effects of changing the land-use from natural forest to other land-uses on carbon stocks in northern Iran. We selected five sites for this study：（I） a natural forest, （II） an agricultural field and （III） plantations of three different species （Alnus subcordata .L, Acer velutinum .Boiss and Cu- pressus sempervirens）. We examined the effects of land-use changes on：（I） soil carbon stock （0-50 cm depth）, （II） biomass and carbon content of grassy vegetation and litter and （III） above- and below-ground biomass C in trees. Soil C stock was higher under A. velutinum and C. sempervirens whereas it was lower under A. subcordata and agricultural sites. Biomass and C content of grassy vegetation were significantly higher at A. veluti- num and C. sempervirens plantations. However, litter biomass and C content were significantly higher at the natural forest site. Natural forest had the highest amount of C content in above- and below-ground bio- mass. Total ecosystem C stocks declined following land-use changes.

关键词： biomass climate change mitigation Hyrcanian forests plan-tation soil organic carbon

A complex solution on the dynamic response of sandwich graphene-reinforced aluminum-based composite beams with copper face sheets under two moving constant loads on an elastic foundation

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International Journal of Mechanical System Dynamics 2023年第3期3卷 251-264页

作者： Mohammadreza Eghbali Seyed Amirhosein hosseini Department of Mechanical Engineering University of ZanjanZanjanIran Department of Industrial Mechanical and Aerospace EngineeringBuein Zahra Technical UniversityQazvinIran

An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functionally graded composite beam and a simply supported boundary ***'s higher-order shear deformation theory was utilized to derive the equations,which were solved in Laplace space and then converted into space–time using Laplace *** exact response of the GRAC sandwich beam was obtained by considering the displacement at the mid-span of the sandwich *** moving loads with different speed ratios were applied at a single point,and the effect of various parameters,including the spring constant,the speed ratio,the percentage of graphene,the moving load speed,and the distribution pattern,was *** study aimed to eliminate any overlap and improve the accuracy of the *** exact solving method presented has not been reported in other articles so ***,due to the difficulty of solving mathematical equations,this method is only applicable to simple boundary conditions.

关键词： GRAC beams moving load Laplace transform elastic foundation analytical solution aluminum-based