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Development of a new generalized correlation to characterize physical properties of pure components and petroleum fractions
, Article Fluid Phase Equilibria ; Vol. 363 , 15 February , 2014 , pp. 189-198 ; ISSN: 03783812 ; Jamshidi, S ; Sharif University of Technology
2014
Abstract
A new generalized and non-group contribution method has been developed to predict critical temperature (Tc), critical pressure (Pc), critical volume (Vc) and acentric factor (ω) for pure substances and petroleum fractions based on two types of input parameters. This method can take either refractive index and molecular weight or refractive index and normal boiling point as its input. Since refractive index cannot be obtained for an unknown mixture (petroleum fraction), in order to apply the proposed method for petroleum fractions, refractive index is converted to mass density at 293K using the one-third rule. Moreover, the proposed correlation is capable of predicting the properties using...
A new correlative model for viscosity estimation of pure components, bitumens, size-asymmetric mixtures and reservoir fluids
, Article Journal of Petroleum Science and Engineering ; Volume 147 , 2016 , Pages 624-635 ; 09204105 (ISSN) ; Jamshidi, S ; Sharif University of Technology
Elsevier B.V
2016
Abstract
Estimation of petroleum fractions properties is one of the major problems in the reservoir fluids analysis, due to the fact that they cannot exactly be diagnosed and their constituents are not available clearly. In this study, a simple model has been developed to estimate the viscosity of pure hydrocarbon substances, bitumens, size-asymmetric mixtures and reservoir fluids (containing unknown hydrocarbon mixtures or petroleum fractions). The proposed model has been extended based on the two conventional and physical properties which can be measured for both pure components and unknown mixtures, without requiring to have their components and compositions. This model uses the pressure (P),...
Determination of perturbed-chain statistical association fluid theory parameters for pure substances, single carbon number groups, and petroleum fractions using cubic equations of state parameters
, Article Industrial and Engineering Chemistry Research ; Volume 54, Issue 45 , 2015 , Pages 11448-11465 ; 08885885 (ISSN) ; Jamshidi, S ; Sharif University of Technology
American Chemical Society
2015
Abstract
A new-generation equation of state, perturbed-chain statistical association fluid theory (PC-SAFT), has attracted much attention to modeling the phase behavior of fluids using molecular-based equations of state. A set of three pure component parameters is needed for non-associative compounds, conventionally determined by fitting vapor pressure and liquid density data simultaneously. Unfortunately, experimental data are scarce, and the number of pure substances is too large. Thus, it is indispensable for developing predictive methods to determine the pure component parameters. In the present paper, a new model has been developed to estimate PC-SAFT parameters for different pure components,...
Static recrystallization behavior of AEREX350 superalloy
, Article Materials Science and Engineering A ; Volume 527, Issue 27-28 , October , 2010 , Pages 7313-7317 ; 09215093 (ISSN) ; Asgari, S ; Sharif University of Technology
2010
Abstract
The recrystallization behavior of a commercial nickel-cobalt base superalloy, AEREX 350, is investigated by means of hardness test, X-ray diffraction, and microscopy. It is found that the alloy resists recrystallization up to a high temperature of 1025 °C. Recrystallized grains are readily formed at grain boundaries below this temperature; however, the growth of these new grains is inhibited by Widmanstätten η particles having coherent facets with the nickel matrix (γ). The passage of the recrystallization front results in coherency loss and consequently dissolution of the η platelets. Recrystallization proceeds with a discontinuous precipitation of the η phase behind the moving boundary
An evolved cubic equation of state with a new attractive term
, Article Fluid Phase Equilibria ; Volume 408 , 2016 , Pages 58-71 ; 03783812 (ISSN) ; Jamshidi, S ; Sharif University of Technology
Elsevier
2016
Abstract
A large variety of modifications have been presented for the temperature dependent function (α) existing in the attractive term of cubic equations of state (CEOS). Most of α-functions attempted to modify the vapor pressure prediction of polar components while other modifications have focused on both polar and non-polar compounds and other relations have considered an expansion of polynomials in the acentric factor (ω) and reduced temperature (Tr) to predict vapor pressure more accurately. In most cases such as Soave and Peng-Robinson equations of state, the suggested α-functions do not show a limiting behavior when temperature increases infinitely. In addition, the incompetency of many...
The effect of cold-rolling prior to the inter-critical heat treatment on microstructure and mechanical properties of 4340 steel with ferrite – Martensite microstructure
, Article Materials Science and Engineering A ; Volume 830 , 2022 ; 09215093 (ISSN) ; Ekrami, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study investigates the effect of cold rolling prior to inter-critical annealing on microstructure and mechanical properties of ferrite-martensite dual phase steel. Samples were heated to 850 °C for 1 h followed by oil quenching, then the steel sheet were cold rolled by 0%,10%,15% and 20% reduction in thickness. The inter-critical annealing treatment (750 °C, 120min) was performed to generate a ferrite-martensite microstructure. Microstructural studies showed that increasing the applied cold rolling, leading to increase in volume fraction of martensite and decrease in ferrite grain size. Mechanical properties of dual phase steel were measured by tensile, impact and hardness tests....
Developing a new model for the determination of petroleum fraction PC-SAFT parameters to model reservoir fluids
, Article Fluid Phase Equilibria ; Volume 412 , 2016 , Pages 145-157 ; 03783812 (ISSN) ; Assareh, M ; Ghotbi, C ; Sharif University of Technology
Elsevier
2016
Abstract
In this work, PC-SAFT, an equation of state based on perturbation theory, is applied to predict the reservoir fluids phase behavior. PC-SAFT parameters for pure components have previously been assessed, but they cannot be determined for petroleum fractions with unspecified components and composition. In order to remove this difficulty and making use of PC-SAFT model in the reservoir fluids simulations, a new approach is studied which leads to appearing generalized correlations for the estimation of PC-SAFT parameters for petroleum cuts and plus fractions using only their molecular weight and specific gravity, without the essential need for the characterization of petroleum fractions in...
Investigation on Effects of Cold Roll Prior to Intercritical Annealing on Microstructure and Mechanical Properties of Ferrite - Martensite Dual Phase Steel
, M.Sc. Thesis Sharif University of Technology ; Ekrami, Ali Akbar (Supervisor)
Abstract
This study investigates effect of cold roll prior to inter-critical annealing on microstructure and mechanical properties of ferrite-martensite dual phase steel. Samples were heated to 850oC for 1h followed by oil quench, then the steel sheet were cold rolled by 0%,10%,15% and 20% reduction in thickness, Then an inter-critical annealing(750oC,120min) was performed to generate a ferrite-martensite microstructure. Microstructural study showed that increase in applied Cold roll, leading to increase volume fraction of martensite and decrease in ferrite grain size. Mechanical properties of dual phase steel were tested by Tensile test, impact test and micro-hardness Test. Results shows that...
Investigation on Effects of Cold Roll Prior to Intercritical Annealing on Microstructure and Mechanical Properties of Ferrite-Martensite Dual Phase Steel
, M.Sc. Thesis Sharif University of Technology ; Ekrami, Ali Akbar (Supervisor)
Abstract
This study investigates effect of cold roll prior to inter-critical annealing on microstructure and mechanical properties of ferrite-martensite dual phase steel. Samples were heated to 850oC for 1h followed by oil quench, then the steel sheet were cold rolled by 0%,10%,15% and 20% reduction in thickness, Then an inter-critical annealing(750oC,120min) was performed to generate a ferrite-martensite microstructure. Microstructural study showed that increase in applied Cold roll, leading to increase volume fraction of martensite and decrease in ferrite grain size. Mechanical properties of dual phase steel were tested by Tensile test, impact test and micro-hardness Test. Results shows that...
Application of the PC-SAFT, an Equation of State Based on Perturbation Theory, to Predict the Phase Behaviour of the Iranian Offshore Oil Company Reservoir Fluids
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
In this work, PC-SAFT, an equation of state based on perturbation theory, is applied to predict the phase behavior of the reservoir fluids. PC-SAFT parameters for pure components are available but they cannot be calculated for petroleum fractions with unspecified components and composition. To solve this problem, and make use of the PC-SAFT model in the reservoir fluids simulations, two approaches are studied. In the first approach new correlations are developed which are able to predict the PC-SAFT parameters for plus fractions based on their molecular weight and mass density. The second approach is to use the artificial neural networks (ANNs) for estimation of PC-SAFT parameters for the...
Secrecy capacity scaling in large cooperative wireless networks
, Article IEEE Transactions on Information Theory ; Volume 63, Issue 3 , 2017 , Pages 1923-1939 ; 00189448 (ISSN) ; Papadimitratos, P. P ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
We investigate large wireless networks subject to security constraints. In contrast to point-to-point, interferencelimited communications considered in prior works, we propose active cooperative relaying-based schemes. We consider a network with nl legitimate nodes, ne eavesdroppers, and path loss exponent α ≥ 2. As long as n2e (log(ne))γ = o(nl ), for some positive γ , we show that one can obtain unbounded secure aggregate rate. This means zero-cost secure communication, given fixed total power constraint for the entire network. We achieve this result through: 1) the source using Wyner randomized encoder and a serial (multi-stage) block Markov scheme, to cooperate with the relays and 2) the...
Fast estimation of connectivity in fractured reservoirs using percolation theory
, Article SPE Journal ; Volume 12, Issue 2 , 2007 , Pages 167-178 ; 1086055X (ISSN) ; King, P. R ; Nuratza, P ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2007
Abstract
Investigating the impact of geological uncertainty (i.e., spatial distribution of fractures) on reservoir performance may aid management decisions. The conventional approach to address this is to build a number of possible reservoir models, upscale them, and then run flow simulations. The problem with this approach is that it is computationally very expensive. In this study, we use another approach based on the permeability contrasts that control the flow, called percolation approach. This assumes that the permeability disorder of a rock can be simplified to either permeable or impermeable. The advantage is that by using some universal laws from percolation theory, the effect of the complex...
A new decoding scheme for errorless codes for overloaded CDMA with active user detection
, Article 2011 18th International Conference on Telecommunications, ICT 2011, Ayia Napa, 8 May 2011 through 11 May 2011 ; 2011 , Pages 201-205 ; 9781457700248 (ISBN) ; Pad, P ; Delgosha, P ; Marvasti, F ; Sharif University of Technology
2011
Abstract
Recently, a new class of binary codes for overloaded CDMA systems are proposed that not only has the ability of errorless communication but also suitable for detecting active users. These codes are called COWDA. In [1], a Maximum Likelihood (ML) decoder is proposed for this class of codes. Although the proposed scheme for coding/decoding shows impressive performance, the decoder can be significantly improved. In this paper, by assuming practical conditions for the traffic in the system, we suggest and prove an algorithm that increases the performance of the decoder several orders of magnitude (the Bit-Error-Rate (BER) is divided by a factor of about 400 in some E b/N0's). The algorithm...
Estimation of the Effective Permeability of Heterogeneous Porous Media by Using Percolation Concepts
, Article Transport in Porous Media ; Volume 114, Issue 1 , 2016 , Pages 169-199 ; 01693913 (ISSN) ; Gago, P. A ; King, P. R ; Sharif University of Technology
Springer Netherlands
2016
Abstract
In this paper we present new methods to estimate the effective permeability (keff) of heterogeneous porous media with a wide distribution of permeabilities and various underlying structures, using percolation concepts. We first set a threshold permeability (kth) on the permeability density function and use standard algorithms from percolation theory to check whether the high permeable grid blocks (i.e., those with permeability higher than kth) with occupied fraction of “p” first forms a cluster connecting two opposite sides of the system in the direction of the flow (high permeability flow pathway). Then we estimate the effective permeability of the heterogeneous porous media in different...
Percolation-based effective permeability estimation in real heterogeneous porous media
, Article 15th European Conference on the Mathematics of Oil Recovery, 29 August 2016 through 1 September 2016 ; 2016 ; 9462821933 (ISBN); 9789462821934 (ISBN) ; Gago, P ; King, P ; DCSE; Schlumberger; Shell ; Sharif University of Technology
European Association of Geoscientists and Engineers
2016
Abstract
It has long been understood that flow behavior in heterogeneous porous media is largely controlled by the continuity of permeability contrasts. With this in mind, we are looking in new methods for a fast estimation of the effective permeability which concentrates on the properties of the percolating cluster. From percolation concepts we use a threshold permeability value (Kth) by which the gridblocks with the highest permeability values connect two opposite side of the system in the direction of the flow. Those methods can be applied to heterogeneous media of a range of permeabilities distribution and various underlying structures. We use power law relations and weighted power averages that...
Optimization of sputtering parameters for the deposition of low resistivity indium tin oxide thin films
, Article Acta Metallurgica Sinica (English Letters) ; Vol. 27, issue. 2 , Apr , 2014 , p. 324-330 ; Bagheri, B ; Yazdanfar, P ; Rashidian, B ; Sasanpour, P ; Sharif University of Technology
2014
Abstract
Indium tin oxide (ITO) thin films have been deposited using RF sputtering technique at different pressures, RF powers, and substrate temperatures. Variations in surface morphology, optical properties, and film resistances were measured and analyzed. It is shown that a very low value of sheet resistance (1.96 ω/sq.) can be achieved with suitable arrangement of the deposition experiments. First, at constant RF power, deposition at different pressure values is done, and the condition for achieving minimum sheet resistance (26.43 ω/sq.) is found. In the next step, different values of RF powers are tried, while keeping the pressure fixed on the previously found minimum point (1-2 Pa). Finally,...
Comparative assessment of gasification based coal power plants with various CO2 capture technologies producing electricity and hydrogen
, Article Energy and Fuels ; Volume 28, Issue 2 , 20 February , 2014 , Pages 1028-1040 ; ISSN: 08870624 ; Kumar, P ; Hosseini, A ; Yang, A ; Fennell, P ; Sharif University of Technology
2014
Abstract
Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool "Aspen Plus". The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2 emission. The effect of air...
Synthesis of nanosize single-crystal hydroxyapatite via mechanochemical method
, Article Materials Letters ; Volume 63, Issue 5 , 2009 , Pages 543-546 ; 0167577X (ISSN) ; Honarmandi, P ; Ebrahimi Kahrizsangi, R ; Honarmandi, P ; Sharif University of Technology
2009
Abstract
Single-crystal hydroxyapatite (HAp) nanorods and nanogranules have been synthesized successfully by a mechanochemical process using two distinct experimental procedures. The experimental outcomes are characterized by transmission electron microscopy (TEM), and powder X-ray diffraction (XRD) techniques. In this work, the feasibility of using polymeric milling media to prepare hydroxyapatite nanoparticles is described. The resulting hydroxyapatite powder exhibits an average size of about 20 to 23 nm. Final results indicate that the proposed synthesis strategy provides a facile pathway to obtain single-crystal HAp with high quality and suitable morphology. © 2008 Elsevier B.V. All rights...
Migrating to Cloud-Native architectures using microservices: An experience report
, Article Workshops on CLIoT, WAS4FI, SeaClouds, CloudWay, IDEA, FedCloudNet 2015 held in conjunction with European Conference on Service-Oriented and Cloud Computing, ESOCC 2015, 15 September 2015 through 17 September 2015 ; Volume 567 , 2016 , Pages 201-215 ; 18650929 (ISSN); 9783319333120 (ISBN) ; Heydarnoori, A ; Jamshidi, P ; Celesti A ; Leitner P ; Sharif University of Technology
Springer Verlag
2016
Abstract
Migration to the cloud has been a popular topic in industry and academia in recent years. Despite many benefits that the cloud presents, such as high availability and scalability, most of the on-premise application architectures are not ready to fully exploit the benefits of this environment, and adapting them to this environment is a non-trivial task. Microservices have appeared recently as novel architectural styles that are native to the cloud. These cloud-native architectures can facilitate migrating on-premise architectures to fully benefit from the cloud environments because non-functional attributes, like scalability, are inherent in this style. The existing approaches on cloud...
Study the effect of connectivity between two wells on secondary recovery efficiency using percolation approach
, Article 15th European Conference on the Mathematics of Oil Recovery, ECMOR 2016, 29 August 2016 through 1 September 2016 ; 2016 ; 9462821933 (ISBN); 9789462821934 (ISBN) ; Masihi, M ; King, P. R ; Gago, P. A ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2016
Abstract
Estimating available hydrocarbon to be produced during secondary oil recovery is an ongoing activity in field development. The primary plan is normally scheduled during early stage of field's life through master development plan studies. During this period, due to the lake of certain data, estimation of the field efficiency is usually based on rules of thumb and not detailed field characterization. Hence, there is a great motivation to produce simpler physically-based methodologies. The minimum necessity inputs of percolation approach make it a useful tool for foration performance prediction. This approach enables us to attain a better assessment of the efficiency of secondary recovery...