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Novel 2D algorithm for fluid solid interaction based on the smoothed particle hydrodynamics (SPH) method
, Article Scientia Iranica ; Volume 18, Issue 3 B , June , 2011 , Pages 358-367 ; 10263098 (ISSN) ; Pisheva, A ; Saidi, M. S ; Sharif University of Technology
2011
Abstract
In this study, a pure Lagrangian algorithm for numerical simulation of fluid-structure interaction problems is proposed based on the Smoothed Particle Hydrodynamics (SPH) method. A new treatment of boundary conditions at the interfaces is introduced that provides the possibility of simultaneous integration of governing equations for all particles, regardless of its material type. The proposed algorithm is capable of dealing with large deformations of hypo elastic solids. The method is validated by comparison of numerical results with other numerical simulations and also examining the consistent behaviors of the algorithm for different parameters
Dynamics of drops - Formation, growth, oscillation, detachment, and coalescence
, Article Advances in Colloid and Interface Science ; Volume 222 , 2015 , Pages 413-424 ; 00018686 (ISSN) ; Taeibi Rahni, M ; Javadi, A ; Cronan, C. L ; Schano, K. H ; Faraji, S ; Won, J. Y ; Ferri, J. K ; Krägel, J ; Miller, R ; Sharif University of Technology
Elsevier
2015
Abstract
Single drops or bubbles are frequently used for the characterization of liquid- fluid interfaces. Their advantage is the small volume and the various protocols of their formation. Thus, several important methods are based on single drops and bubbles, such as capillary pressure and profile analysis tensiometry. However, these methods are often applied under dynamic conditions, although their principles are defined under equilibrium conditions. Thus, specific attention has to be paid when these methods are used beyond certain limits. In many cases, computational fluid dynamics (CFD) simulations have allowed researchers, to extend these limits and to gain important information on the...
Robust 1-d fluid flow and heat transfer predictions in gas turbine cooling passages
, Article AIAA Propulsion and Energy Forum and Exposition, 2019, 19 August 2019 through 22 August 2019 ; 2019 ; 9781624105906 (ISBN) ; Darbandi, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA
2019
Abstract
This study describes a 1-D code, which determines the one-dimensional flow and heat transfer distributions in arbitrarily connected flow passages with multiple inlets and outlets. The procedure uses a component solver, which solves the one-dimensional compressible fluid flow and heat transfer equations inside an individual cooling passage. Also, it uses experimental correlations for the heat transfer coefficient and friction factor for each cooling passage. In addition to the component solver, there is a flow network solver subroutine, which applies the mass and energy conservation equations properly at each internal node. In order to validate this 1-D code, both the component and the flow...
Robust 1-d fluid flow and heat transfer predictions in gas turbine cooling passages
, Article AIAA Propulsion and Energy Forum and Exposition, 2019, 19 August 2019 through 22 August 2019 ; 2019 ; 9781624105906 (ISBN) ; Darbandi, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA
2019
Abstract
This study describes a 1-D code, which determines the one-dimensional flow and heat transfer distributions in arbitrarily connected flow passages with multiple inlets and outlets. The procedure uses a component solver, which solves the one-dimensional compressible fluid flow and heat transfer equations inside an individual cooling passage. Also, it uses experimental correlations for the heat transfer coefficient and friction factor for each cooling passage. In addition to the component solver, there is a flow network solver subroutine, which applies the mass and energy conservation equations properly at each internal node. In order to validate this 1-D code, both the component and the flow...
Pore scale visualization of fluid-fluid and rock-fluid interactions during low-salinity waterflooding in carbonate and sandstone representing micromodels
, Article Journal of Petroleum Science and Engineering ; 2020 ; Fatemi, M ; Masihi, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Low Salinity Waterflooding (LSWF) has become a popular tertiary injection EOR method recently. Both fluid-fluid and fluid-rock interactions are suggested as the contributing mechanisms on the effectiveness of LSWF. Considering the contradictory remarks in the literature, the dominating mechanisms and necessary conditions for Low Salinity Effect (LSE) varies for different crude oil-brine-rock (CBR) systems. The aim of the present study is to investigate LSE for an oil field in the Middle East that is composed of separate sandstone and limestone layers. Contact angles and Interfacial Tension (IFT) are measured to have more insight on the CBR under investigation. Visual experiments were...
Performance evaluation and improvement of PC-SAFT equation of state for the asphaltene precipitation modeling during mixing with various fluid types
, Article Fluid Phase Equilibria ; Volume 554 , 2022 ; 03783812 (ISSN) ; Jamshidi, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
One of the significant problems of the upstream flow assurance community is precipitation or deposition of asphaltene that leads to affect the economics of oil production seriously. Knowledge of asphaltene onset pressure (AOP) and amount of asphaltene precipitation in the change of temperature, pressure, and composition is the essential information for preventing this problem. Recent studies have shown that thermodynamic models based on the solubility nature of asphaltenes using an equation of state (EOS) are the most effective approach to asphaltene behavior modeling. In this research, the common version of the SAFT equation, known as the Perturbed Chain form of Statistical Association...
Computer simulation of the effect of particle stiffness coefficient on the particle-fluid flows
, Article Particulate Science and Technology ; Volume 40, Issue 2 , 2022 , Pages 233-242 ; 02726351 (ISSN) ; Rajabi, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The Computational fluid dynamics (CFD)–discrete element method (DEM) numerical simulation may be applied to predict the hydrodynamic behavior of dense particle–fluid flows. The main drawback of this simulation is the long computational time required owing to the large number of particles and the minute time-step required to maintain a stable solution. In this work, a new method to improve the efficiency and accuracy of CFD–DEM simulations is presented. The particle stiffness coefficient is used as a flexible parameter to improve the accuracy and efficiency of the model. The particle concentration distribution results are compared with experimental one’s to derive the optimum effective...
Nonlinear vibrations and stability of rotating cylindrical shells conveying annular fluid medium
, Article Thin-Walled Structures ; Volume 171 , 2022 ; 02638231 (ISSN) ; Firouz abadi, R. D ; Rahmanian, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study aims to investigate the nonlinear dynamic characteristics of annular cylinders coupled with a fluid medium to identify the effective parameters on stability margins at different rotation speeds. To achieve this, stability and nonlinear vibrations of rotating cylindrical shells containing incompressible annular fluid are considered. The fluid medium is bounded by a rigid external cylinder. Sanders–Koiter kinematic assumptions are utilized to determine the geometrically nonlinear structural equations of motion. These equations are then used to investigate finite amplitude vibrations of various fluid-loaded shells at different states. A penalty approach is introduced by using...
Experimental Analysis of the Effect of Fluid/Fluid and Fluid/Rock Interactions on the Pore Scale Displacement Mechanisms of Oil by Lswi
, M.Sc. Thesis Sharif University of Technology ; Fatemi, Mobeen (Supervisor) ; Masihi, Mohsen (Supervisor)
Abstract
Visual investigation of the low salinity water injection into micromodel is the goal of this research. Although many researches have been performed to realize the dominating mechanism behind the increased oil recovery after low salinity water injection, many contradictions exist among the studies. Mechanisms are generally divided into two classes. One class is due to fluid/fluid interactions and the other one is due to fluid/rock interactions. A comprehensive set of experiments are conducted in this study to find out the dominating mechanism behind low salinity water injection under the existing conditions of the experiments. Effect of different wettability condition and presence and absence...
Experimental Investigation of the Hole Cleaning Process in Horizontal and Inclined Wells Using a Custom-Made Water-Based Drilling Fluid
, M.Sc. Thesis Sharif University of Technology ; Taghi khani, Vahid (Supervisor) ; Tahmasebi, Korosh (Co-Supervisor) ; Kalhor, Mogtaba (Co-Supervisor)
Abstract
Currently, drilling such as vertical or straight-hole drilling, i.e. usually less than 30 degrees inclined, or deflection drilling is used to drill at conventional and even unconventional reservoirs around the world to increase recovery factor and productivity. A major challenge is cleaning the hole or removing debris which if not done properly can lead to problems such as stuck pipes. In addition, Improper use of drilling fluid in terms of rheological properties in different stages of drilling operations can cause the well to collapse due to the accumulation of particles in the annular space. The transfer speed of particles is very important in cleaning the well. Inefficient cleaning of...
Simulation of Drilling Fluid Movement Using Neural Network Modeling and Comparison with CFD Methods
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeid (Supervisor)
Abstract
We report on numerical and intelligent modeling of three-dimensional laminar flow of non-Newtonian fluids driven by axial pressure gradient in annular media consisting of a coaxially rotating inner cylinder. This is an example of a rotating Couette flow with vast applications in food, oil and gas, and chemical engineering industries. We study the dynamics of pressure in and the velocities (in three directions X, Y and Z) of every grid in presence of rotation and without that by means of CFD. Afterward, we develop a novel predictive model based on an Artificial Neural Network (ANN). The hybrid ANN framework is trained and tested by over 100000 data which collected by CFD. We then perform...
Cubic nonlinear analysis of interaction between a surface wave and two interfacial waves in an open two-layer fluid
, Article Fluid Dynamics Research ; Volume 44, Issue 5 , June , 2012 ; 01695983 (ISSN) ; Jamali, M ; Sharif University of Technology
IOP
2012
Abstract
A third-order asymptotic analysis is conducted to study the three-dimensional resonant interaction between a monochromatic progressive surface wave and two oblique interfacial waves in an open, lightly viscous, two-layer fluid of intermediate depth. By solving the evolution equations of the waves, the short- and long-term behaviors of the interfacial waves are studied. The analysis provides a correction to the second-order theory. The results indicate that the third-order analysis predicts a much lower limit on the growth of the interfacial waves than the second-order theory. Furthermore, in the long term, viscous effects cause the interfacial wave amplitudes to approach a constant value....
Experimental study of the effects of ferrofluid on thermal performance of a pulsating heat pipe
, Article ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2011 ; Volume 1 , 2011 , Pages 435-440 ; 9780791844632 (ISBN) ; Mohammad, M ; Amir, R. G ; Shafii, M. B ; Sharif University of Technology
2011
Abstract
In this work, a four-turn Pulsating Heat Pipe (PHP) is fabricated and tested experimentally. The novelty of the present PHP is the capability of obtaining various thermal performances at a specific heat input by changing the magnetic field. The effects of working fluid (water and ferrofluid), charging ratio (25%, 40%, and 55%), heat input (25, 35, 45, 55, 65, 75, and 85 W), orientation (vertical and horizontal heat mode), and magnetic field on the thermal performance of PHPs are investigated. The results showed that applying the magnetic field on the water based ferrofluid reduced the thermal resistance of PHP by a factor of 40.5% and 38.3% in comparison with the pure water case for the...
Numerical investigation of a stepped planing hull in calm water
, Article Ocean Engineering ; Volume 94 , January , 2015 , Pages 103-110 ; 00298018 (ISSN) ; Ashrafizaadeh, M ; Esfahan, R. K ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Stepped planing hulls enable the feasibility of running at relatively low Drag-Lift ratio by means of achieving more optimal trim angle at high speeds. Currently, there is no precise method to analyze these hulls over the full range of operating speeds. In this study, a three-dimensional computational fluid dynamics (CFD) model using volume of fluid (VOF) approach is presented for examining the characteristics of a planing hull having one transverse step. A procedure is presented to transform a series of fixed-position simulations into a free to heave and pitch simulation. Resistance, lift, running draft, dynamic trim angle, and wetted area are compared with available experimental data and...
DPD simulation of electroosmotic flow in nanochannels and the evaluation of effective parameters
, Article 10th AIAA/ASME Joint Thermophysics and Heat Transfer Conference, 28 June 2010 through 1 July 2010, Chicago, IL ; 2010 ; 9781600867453 (ISBN) ; Zakeri, R ; Schneider, G. E ; Sharif University of Technology
2010
Abstract
We provide the simulation of electroosmotic phenomenon in nanochannels using the Dissipative Particle Dynamics (DPD) method. We study the electroosmotic phenomenon for both newtonian and non-newtonian fluids. Literature shows that most of past electroosmotic studies have been concentrated on continuum newtonian fluids. However, there are many nano/microfluidic applications, which need to be treated as either non-newtonian fluids or non-continuum fluids. In this paper, we simulate the electroosmotic flow in nanochannel considering no limit if it is neither continuum nor non-nonewtonian. As is known, the DPD method has several important advantages compared with the classical molecular dynamics...
CFD Simulation of hydrodynamic of a bubble column reactor operating in churn-turbulent regime and effect of gas inlet distribution on system characteristics
, Article International Journal of Chemical Reactor Engineering ; Volume 14, Issue 1 , 2016 , Pages 213-224 ; 15426580 (ISSN) ; Zarkesh, J ; Rashtchian, D ; Anvari, A ; Sharif University of Technology
Walter de Gruyter GmbH
Abstract
CFD simulation of cylindrical bubble column including air as dispersed phase and water as continuous phase operating in churn-turbulent flow regime with diameter of 0.49 m, height of 3.6 m and gas superficial velocity of 0.14 m/s have been conducted. All simulations have been carried out in a 2D axisymmetric, unsteady and Euler/Euler framework with the aid of commercial software FLUENT v. 14.5. Simulations were validated by our experimental results through residence time distribution (RTD) data. Effect of bubble size distribution at inlet on column hydrodynamic was investigated and results clearly showed that equilibrium bubble size distribution in most parts of column is independent of...
Dynamics and stability of conical/cylindrical shells conveying subsonic compressible fluid flows with general boundary conditions
, Article International Journal of Mechanical Sciences ; Volume 120 , 2017 , Pages 42-61 ; 00207403 (ISSN) ; Firouz Abadi, R. D ; Cigeroglu, E ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
A fast and efficient reduced order formulation is presented for the first time to study dynamics and stability of conical/cylindrical shells with internal fluid flows. The structural and fluid formulations are developed based on general assumptions to avoid any deficiency due to modeling. Their respective solutions and the final solution to the coupled field problem are also developed in a way to be capable of capturing any desirable set of boundary conditions. In addition to the flexibility provided by the solution methodology and generalization provided by the formulation, current solution proposes an additional advantage over others which is the minimal computational cost due to the...
A recent review of waste heat recovery by Organic Rankine Cycle
, Article Applied Thermal Engineering ; Volume 143 , 2018 , Pages 660-675 ; 13594311 (ISSN) ; Fazli, M ; Morad, M. R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The increment of using fossil fuels has caused many perilous environmental problems such as acid precipitation, global climate change and air pollution. More than 50% of the energy that is used in the world is wasted as heat. Recovering the wasted heat could increase the system efficiency and lead to lower fuel consumption and CO2 production. Organic Rankine cycle (ORC) which is a reliable technology to efficiently convert low and medium temperature heat sources into electricity, has been known as a promising solution to recover the waste heat. There are numerous studies about ORC technology in a wide range of application and condition. The main objective of this paper is to presents a...
New correlative models to improve prediction of fracture permeability and inertial resistance coefficient
, Article Transport in Porous Media ; Volume 121, Issue 3 , February , 2018 , Pages 557-584 ; 01693913 (ISSN) ; Jamshidi, S ; Pishvaie, M. R ; Sharif University of Technology
Springer Netherlands
2018
Abstract
Presence of fracture roughness and occurrence of nonlinear flow complicate fluid flow through rock fractures. This paper presents a qualitative and quantitative study on the effects of fracture wall surface roughness on flow behavior using direct flow simulation on artificial fractures. Previous studies have highlighted the importance of roughness on linear and nonlinear flow through rock fractures. Therefore, considering fracture roughness to propose models for the linear and nonlinear flow parameters seems to be necessary. In the current report, lattice Boltzmann method is used to numerically simulate fluid flow through different fracture realizations. Flow simulations are conducted over a...
Numerical modeling and simulation of drilling cutting transport in horizontal wells
, Article Journal of Petroleum Exploration and Production Technology ; Volume 8, Issue 2 , 2018 , Pages 455-474 ; 21900558 (ISSN) ; Sarafraz, S ; Tabzar, A ; Hemmati, N ; Shadizadeh, S. R ; Sharif University of Technology
Springer Verlag
2018
Abstract
Cutting transport is an important goal in drilling operation especially in horizontal and deviated wells since it can cause problems such as stuck pipe, circulation loss and high torque and drag. To this end, this article focused on the affecting parameters on the cutting transport by computational fluid dynamic (CFD) modeling and real operational data. The effect of drilling fluid and cutting density on the pressure drop, deposit ratio and string stress on the cutting transport has been investigated. A systematic validation study is presented by comparing the simulation results against published experimental database. The results showed that by increasing two times of drilling fluid...