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Insight into heavy oil recovery of cyclic solvent injection (CSI) utilizing C_(3)H_(8)/CH_(4) and C_(3)H_(8)/CH_(4)/CO_(2)

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Petroleum 2018年第3期4卷 337-346页

作者： arash Ahadi Farshid Torabi Petroleum Systems Engineering University of ReginaSKS4S 0A2Canada

In this study,a sandpack model with porosity and permeability of 32.3%and 9.4 D,and a heavy crude oil with viscosity of 6430 mPa.s were used to represent a typical thin heavy oil ***,different ratios of C3H8 to CH4 stream were prepared and their performance on Cyclic Solvent Injection(CSI)method was examined to quantify the optimum solvent ***,CO2 was introduced to the optimum quantified CH4-C3H8 mixture to investigate the extent to which CSI behavior changes by partially replacement of CH4 with *** showed that ultimate oil recovery factor(RF)increased from 24.3%to 33.4%original oil in place(OOIP)when C3H8 concentration increased from 15 to 50 mol%in the CH4 *** tests with higher C3H8 concentration reached the maximum cyclic recovery with lower number of injection cycles-due to higher solubility of C3H8 compared with *** utilization factor(SUF)data also confirmed this as lesser volume of solvent with higher C3H8 concentration was required to produce *** observations showed that the produced foamy oil lasted longer with higher concentration of C3H8 in the solvent(5 min for 15%C3H8 e 85%CH4 case versus 180min for 50%C3H8 e 50%CH4 case).Upon addition of CO2 to the mixture,the solvent apparent solubility increased and foamy oil flow *** highest cyclic C3H8-CH4 apparent solubility of 0.175 ***/100 *** oil jumped to 0.53 ***/100 *** oil when 35%mole fraction of CO2 replaced *** highest ultimate oil RF of 44.11%OOIP was measured from eight cycle injection of 50%C3H8 e 15%CH4 e 35%*** solvent also benefited from the longest stability of produced-oil foamy shape with recorded time of 217 min(including production time).According to the results of this experimental study,it seems that there is an optimum fraction of C3H8 in CH4 stream injection in heavy oil systems(with viscosity in the vicinity of 6430 mPa s);the concentration beyond which ultimate oil recovery factor

关键词： CSI Solubility Heavy oil Foam stability Light hydrocarbons

Enduring effect of permeability texture for enhancing accuracy and reducing uncertainty of reservoir fluid flow through porous media

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Petroleum Science 2020年第1期17卷 118-135页

作者： arash Azamifard Fariborz Rashidi Mohammadreza Pourfard Mohammad Ahmadi Bahram Dabir Department of Petroleum Engineering Amirkabir University of Technology424 Hafez AveTehranIran Department of Chemical Engineering Amirkabir University of Technology424 Hafez AveTehranIran Department of Electrical Engineering Amirkabir University of Technology424 Hafez AveTehranIran

Modeling reservoir permeability is one of the crucial tasks in reservoir simulation ***,it is done by kriging-based *** rigorous modeling of the permeability results in more reliable outputs of the reservoir ***,a new category of geostatistical methods has been used for this purpose,namely multiple point statistics(MPS).By this new category of permeability modeling methods,one is able to predict the heterogeneity of the reservoir permeability as a continuous *** methods consider the direction of property variation in addition to the distances of known locations of the *** this study,the reservoir performance of a modified version of the SPE 10 solution project as a pioneer case is used for investigating the efficiency of these methods and paralleling them with the kriging-based *** this way,the permeability texture concept is introduced by applying some MPS *** study is accomplished in the conditions of real reservoir dimensions and velocities for the whole reservoir life.A continuous training image is used as the input of calculation for the permeability *** results show that the detailed permeability of the reservoir as a continuous variable makes the reservoir simulation show the same fluid front movement and flooding behavior of the reservoir similar to the reference case with the same permeability *** MPS methods enable the reservoir simulation to reproduce the fluid flow complexities such as bypassing and oil trapping during water flooding similar to the reference ***,total oil production is predicted with higher accuracy and lower *** studied cases are identical except for the permeability *** histograms and variograms of permeabilities for the studied reservoir are quite similar,but the performance of the reservoir shows that kriging-based method results have slightly less accuracy than some MPS ***,it results in lower

关键词： Multiple point statistics Permeability modeling Fluid flow in porous media Permeability texture

Prediction of roadheaders' performance using artificial neural network approaches (MLP and KOSFM)

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第5期7卷 573-583页

作者： arash Ebrahimabadi Mohammad Azimipour Ali Bahreini Department of Mining Islamic Azad University Qaemshahr Branch Department of Water and Wastewater Engineering Faculty of Water Engineering and Environment Shahid Beheshti University Department of Petroleum Faculty of Engineering Science & Research Branch Islamic Azad University

A pplication o f m echanical excavators is one o f th e m o st com m only used excavation m eth o d s because itcan bring th e p ro ject m ore productivity, accuracy and safety. A m ong th e m echanical excavators, roadhead ers are m echanical m iners w h ich have b een extensively u se d in tu n n elin g , m ining an d civil indu stries. Perform ance pred ictio n is an im p o rta n t issue for successful ro a d h e a d e r application andgenerally deals w ith m achine selection, p ro d u ctio n rate an d b it consu m p tio n . The m ain aim o f thisresearch is to investigate th e c u ttin g p erfo rm an ce （in stan tan eo u s c u ttin g rates （ICRs）） o f m ed iu m -d u tyro ad h ead ers by using artificial neural n etw o rk （ANN） approach. T here are d ifferent categories forANNs, b u t based o n train in g alg o rith m th e re are tw o m ain k in d s： supervised and u n su p erv ised . Them u lti-lay er p ercep tro n （MLP） an d K ohonen self-organizing feature m ap （KSOFM） are th e m o st w idelyused neu ral netw o rk s for supervised an d u n su p erv ised ones, respectively. For gaining this goal, ad atab ase w as prim arily provided from ro ad h e a d e rs＇ p erfo rm an ce an d geom echanical characteristics o frock form ations in tu n n els and d rift galleries in Tabas coal m ine, th e larg est an d th e only fullymech an ized coal m ine in Iran. T hen th e datab ase w as analyzed in o rd e r to yield th e m ost im p o rtan tfactor for ICR by using relatively im p o rta n t factor in w hich G arson eq u atio n w as utilized. The MLPn etw o rk w as train ed by 3 in p u t p ara m e te rs including rock m ass pro p erties, rock quality d esignation（RQD）, in tact rock p ro p erties such as uniaxial com pressive stre n g th （UCS） an d Brazilian ten sile stren g th（BTS）, and o n e o u tp u t p a ra m e te r （ICR）. In o rd e r to have m ore v alidation o n MLP o u tp u ts, KSOFM visualizationw as applied. The m ean square e rro r （MSE） an d regression coefficient （R

关键词： Artificial neural network(ANN) Performance prediction Roadheader Instantaneous cutting rate(ICR) Tabas coal mine project

Design and evaluation of a two-section canopy shaker with variable frequency for mechanical harvesting of citrus

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 77-87页

作者： Yingjun Pu arash Toudeshki Reza Ehsani Fuzeng Yang College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina School of Engineering University of CaliforniaMercedCA 95343USA Citrus Research&Education Center Institute of Food and Agricultural SciencesUniversity of FloridaLake AlfredFL 33850USA

Canopy shaking is one of the most commonly used techniques for mechanical harvesting of citrus fruits in orange juice ***,tree damage and low harvesting efficiency are the top concerns of growers in adopting the existing harvesting equipment on a large *** purpose of this research was to develop a novel canopy shaking system to minimize tree damage and maximize fruit removal for mechanical citrus *** this study,a two-section canopy shaker composing of top and bottom shaking systems mounted on two rotating drums was proposed and *** was configured with two sets of flexible bow-shaped shaking rods in a staggered distribution,which can shake the top and bottom zones of the tree canopy *** shaking system was designed based on a linked crank-rocker *** simulation analysis was conducted to verify the quick return characteristics and differential properties of this *** test showed that the frequency of the shaking rod could be adjusted within a range of 1.1-8.8 Hz related to hydraulic motor *** field tests of the shaking system with an average frequency of 4.7 Hz achieved a fruit removal percentage of 82.6%and tree damage rate of 5.4%under a tractor speed of 3 km/*** contrast,the combined shaking frequency of 4.7 Hz&4.1 Hz of the canopy shaker produced less tree damage with a percentage of 3.9%.This study indicated that the two-section canopy shaker with an optimized frequency combination could be adaptable to the different zones of the tree canopy,and obtain lower tree damage and higher fruit removal percentage.

关键词： two-section canopy shaker crank-rocker mechanism variable frequency fruit removal percentage tree damage rate citrus mechanical harvesting

Elastic and optical properties of zinc-blende CrSb and its effective mass

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Rare Metals 2014年第5期33卷 615-621页

作者： Sahar Rezaee arash Boochani Masoud Majidiyan Atefeh Ghaderi Shahram Solaymani Mosayeb Naseri Department of Physics College of ScienceIslamic Azad University Physics Department Sabzevar Tarbiat Moallem University Young Researchers and Elite Club Islamic Azad University

The elastic, optical, and effective mass properties of CrSb in zinc-blende（ZB） phase were *** calculations were carried out using the full-potential linearized augmented plane wave plus local orbital according to the density functional theory. The results of elastic calculations by generalized gradient approximation and local density approximation approximations indicate that ZB CrSb is a ductile material and its Debye temperature is rather low. Band structure and density of state calculations introduce the ZB CrSb as a half-metal with spin polarization of100 %. In metal state, 16 th and 17 th bands cut off the Fermi level. Calculations study the effective mass, Fermi velocity,and Fermi surface at 16 th and 17 th bands. In continue,optical quantities such as dielectric function, energy loss function, and optical conductivity were investigated.

关键词： Half-metal CrSb Elastic properties Optical properties

New method for estimating flying capacitor voltages in stacked multicell and flying capacitor multicell converters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第8期11卷 654-662页

作者： arash KHOSHKBAR SADIGH Gevorg B.GHAREHPETIAN Seyed Hossein HOSSEINI Faculty of Electrical & Computer Engineering University of Tabriz Department of Electrical Engineering Amirkabir University of Technology

Multicell converters are an interesting alternative for medium voltage and high power applications,because of the increased number of output voltage levels and apparent *** two most significant types of multicell converter are the flying capacitor multicell (FCM) converter and its derivative,stacked multicell (SM) *** flying capacitor voltages is an important constraint to the proper performance of FCM and SM ***,observation of the flying capacitor voltages used in active control is valuable,but using voltage sensors for observation increases cost and size of the *** paper deals with a new strategy to estimate the flying capacitor voltages of both FCM and SM *** proposed strategy is based on a discrete time model of the converter and uses only a load current *** circuit was simulated using PSCAD/EMTDC software and simulation results were presented to validate the effectiveness of the proposed estimation strategy in observing the flying capacitor *** is the most significant advantage of the proposed strategy,its performance being based on simple equations.

关键词： Flying capacitor multicell converter Stacked multicell converter Flying capacitor voltage Phase shifted sinusoidal pulse width modulation

Mononitration of phenol derivatives by guanidinium nitrate and silica sulfuric acid under mild conditions

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Chinese Chemical Letters 2011年第12期22卷 1431-1434页

作者： arash Ghorbani-Choghamarani Hamid Goudarziafshar Mohsen Nikoorazm Zahra Naseri Department of Chemistry Faculty of ScienceIlain UniversityP.O.Box 69315516IlamIran

A mixture of guanidinium nitrate and silica sulfuric acid acts as mild and heterogeneous media for the efficient mono nitration of phenolic compounds in dichloromethane at room temperature.

关键词： Nitration Phenol Heterogeneous Guanidinium nitrate Silica sulfuric acid

Electrochemical response of MgO/Co_(3)O_(4) oxide layers produced by plasma electrolytic oxidation and post treatment using cobalt nitrate

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Journal of Magnesium and Alloys 2023年第3期11卷 1057-1073页

作者： Mosab Kaseem Tehseen Zehra Tassawar Hussain Young Gun Ko arash Fattah-alhosseini Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Republic of Korea Materials Electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan 38541Republic of Korea Department of Materials Engineering Bu-Ali Sina UniversityHamedan 65178-38695Iran

This work looked into the influence of the sealing treatment on the structural feature and electrochemical response of AZ31 Mg alloy coated via plasma electrolytic oxidation(PEO).Here,the inorganic layers produced by PEO in an alkaline-phosphate electrolyte were subsequently immersed for different periods in cold(60°C)and hot(100°C)aqueous solutions containing either 1 or 3 gr of cobalt nitrate hexahydrate in the presence of hydrogen peroxide as an *** results showed that the sealing treatments in the hot solutions could trigger the hydration reactions of PEO coating which would largely assist the surface incorporation of Co_(3)O_(4)into the *** contrast,the sealing in cold solutions led to less compact coatings,which was attributed to the fact the hydration reactions would be restricted at 60°C.A nearly fully sealed coating with a porosity of~0.5%was successfully formed on the sample immersed in the hot solution containing 1 gr of cobalt nitrate ***,the electrochemical stability of this fully sealed coating was superior to the other samples as it had the lowest corrosion current density(4.71×10^(-10)A·cm^(-2))and the highest outer layer resistance(3.81×10^(7)Ω·cm^(2)).The composite coatings developed in this study are ideal for applications requiring high electrochemical stability.

关键词： AZ31 Mg alloy Plasma electrolytic oxidation Co_(3)O_(4) Hydration Corrosion

Classical Fourier Analysis over Homogeneous Spaces of Compact Groups

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Analysis in Theory and Applications 2016年第4期32卷 339-354页

作者： arash Ghaani Farashahi Numerical Harmonic Analysis Group (NuHAG) Faculty Mathematics University of Vienna

This paper introduces a unified operator theory approach to the abstract Fourier analysis over homogeneous spaces of compact groups. Let G be a compact group and H be a closed subgroup of G. Let G/H be the left coset space of H in G and μ be the normalized G-invariant measure on G/H associated to the Weil＇s formula. Then, we present a generalized abstract framework of Fourier analysis for the Hilbert function space L^2 （G / H, μ）.

关键词： Compact group homogeneous space dual space Fourier transform Plancherel(trace) formula Peter-Weyl Theorem