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A fully explicit incompressible Smoothed Particle Hydrodynamics method for multiphase flow problems
, Article Engineering Analysis with Boundary Elements ; Volume 143 , 2022 , Pages 501-524 ; 09557997 (ISSN) ; Hopp Hirschler, M ; Shadloo, M. S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Multiphase flow is a challenging area of computational fluid dynamics (CFD) due to their potential large topological change and close coupling between the interface and fluid flow solvers. As such, Lagrangian meshless methods are very well suited for solving such problems. In this paper, we present a new fully explicit incompressible Smoothed Particle Hydrodynamics approach (EISPH) for solving multiphase flow problems. Assuming that the change in pressure between consecutive time-steps is small, due to small time steps in explicit solvers, an approximation of the pressure for following time-steps is derived. To verify the proposed method, several test cases including both single-phase and...
Heat transfer intensification of turbulent forced convection by inserting discontinuous twisted tapes in a wavy tube; hydrothermal and thermodynamics analysis
, Article Chemical Engineering and Processing - Process Intensification ; Volume 181 , 2022 ; 02552701 (ISSN) ; Sadrhosseini, H ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The current study presents a numerical investigation on turbulent hydrothermal characteristics in a wavy passage equipped with discontinuous twisted tapes. The working fluid is water and passage walls are kept under constant wall temperature. The effect of Reynolds number (Re = 2500, 4500, 6500, 8500 and 10500), twist angle (TA = 90∘ and 180∘) and inclination angle (IA = 15∘ and 30∘) on velocity fields and streamlines, temperature contours, Nusselt number, friction factor, turbulent kinetic energy (TKE), thermal performance factor (TPF), energy efficiency factor (EEF) and entropy generation rate are evaluated. More uniform temperature and velocity fields can be found as both wavy passage and...
Numerical simulation of vortex-induced vibration of a smooth circular cylinder at the subcritical regime
, Article Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment ; Volume 236, Issue 4 , 2022 , Pages 916-937 ; 14750902 (ISSN) ; Nemati Kourabbasloo, N ; Mohtat, P ; Tanha, A ; Sharif University of Technology
SAGE Publications Ltd
2022
Abstract
The present paper focuses on the simulation of vortex-induced vibration (VIV) of a rigid, smooth circular cylinder with elastic supports subject to a cross-flow at the subcritical regime of Reynolds number, 30,000
The effect of Ag incorporation on the characteristics of the polymer derived bioactive silicate phosphate glass-ceramic scaffolds
, Article Boletin de la Sociedad Espanola de Ceramica y Vidrio ; Volume 61, Issue 6 , 2022 , Pages 653-663 ; 03663175 (ISSN) ; Godary, T ; Khalilifard, R ; Malek Khachatourian, A ; Abdollahi, F ; Abdollahi, S ; Sharif University of Technology
Sociedad Espanola de Ceramica y Vidrio
2022
Abstract
In the bone tissue engineering field (BTE), it is of significant importance to develop bioactive multifunctional scaffolds with enhanced osteoconductivity, osteoinductivity, and antibacterial properties required for lost bone tissue regeneration. In this work, a bioactive glass-ceramic scaffold was manufactured via a novel polymer-derived ceramics (PDC) manufacturing method. To gain antibacterial properties, the silver ions were incorporated in controlled amount along with other precursors in the PDC processing stage. Microstructural and structural properties of the fabricated silicate-phosphate glass-ceramic scaffold were evaluated by scanning electron microscopy (SEM) equipped with energy...
Continuous submicron particle separation Via Vortex-Enhanced ionic concentration polarization: a numerical investigation
, Article Micromachines ; Volume 13, Issue 12 , 2022 ; 2072666X (ISSN) ; Amiri, H.A ; Collins, D.J ; Miansari, M ; Sharif University of Technology
MDPI
2022
Abstract
Separation and isolation of suspended submicron particles is fundamental to a wide range of applications, including desalination, chemical processing, and medical diagnostics. Ion concentration polarization (ICP), an electrokinetic phenomenon in micro-nano interfaces, has gained attention due to its unique ability to manipulate molecules or particles in suspension and solution. Less well understood, though, is the ability of this phenomenon to generate circulatory fluid flow, and how this enables and enhances continuous particle capture. Here, we perform a comprehensive study of a low-voltage ICP, demonstrating a new electrokinetic method for extracting submicron particles via flow-enhanced...
Numerical study of the effect of hemodynamic variables on LDL concentration through the single layer of the Left Anterior Descending coronary artery (LAD) under the heart pulse
, Article Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine ; Volume 236, Issue 7 , 2022 , Pages 994-1008 ; 09544119 (ISSN) ; Seyedhossein, S. S ; Firoozabadi, B ; MomeniLarimi, M ; Sharif University of Technology
SAGE Publications Ltd
2022
Abstract
Heart attack is one of the most common causes of death in the world. Coronary artery disease is the most recognized cause of heart attack whose onset and progression have been attributed to low-density lipoprotein (LDL) passing through the wall of the artery. In this paper, hemodynamic variables as well as the concentration of LDL through the coronary porous artery at the Left Anterior Descending coronary artery (LAD), and its first diagonal branch (D1) under the heart motion investigated using computational simulation. The geometry that has been studied in this paper is the first bifurcation of Left Anterior Descending (LAD) that has been placed on a perimeter of hypothetical sphere...
Melting process of various phase change materials in presence of auxiliary fluid with sinusoidal wall temperature
, Article Journal of Energy Storage ; Volume 52 , 2022 ; 2352152X (ISSN) ; Khademi, A ; Ushak, S ; Alotaibi, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This paper presents a numerical simulation approach to investigate the water effect as an auxiliary fluid in direct contact with various phase change materials (PCMs). The technique is defined as a hybrid method due to the using of an external intermediary for melting process improvement. Oleic acid (OA), coconut oil (CO), hexadecane, and heptadecane are selected as PCMs due to immiscibility in water and differences in density, melting point, and enthalpy of fusion. An auxiliary fluid is embedded above PCM in an enclosure subjected to sinusoidal wall temperature for melting rate increase through density differences improving heat transfer rate due to materials displacement during process....
On the thermal performance enhancement of spiral-coil energy piles with a thermal recovery system
, Article Energy and Buildings ; Volume 269 , 2022 ; 03787788 (ISSN) ; Asgari, B ; Hakkaki Fard, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The pile foundation designed to ensure building stability when equipped with heat exchanger pipes to harvest geothermal energy is called an energy pile. Ground Source Heat Pump (GSHP) systems combined with energy piles have been used and developed as sustainable and efficient HVAC systems. Energy piles suffer from cold or heat accumulation in and around the pile, degrading their long-term performance. The current study seeks to alleviate this problem by proposing a thermal recovery system. The proposed system circulates ambient air in the pile foundation to extract the accumulated heat. A three-dimensional transient computational fluid dynamics model of the GSHP system coupled with the...
Thermal characteristics of kerosene oil-based hybrid nanofluids (Ag-MnZnFe2O4): A comprehensive study
, Article Frontiers in Energy Research ; Volume 10 , 2022 ; 2296598X (ISSN) ; Ali, K ; Haider, T ; Jamshed, W ; Tag El Din, E. S. M ; Hussain, S. M ; Sharif University of Technology
Frontiers Media S.A
2022
Abstract
Hybrid nanofluids are new and most fascinating types of fluids that involve superior thermal characteristics. These fluids exhibit better heat-transfer performance as equated to conventional fluids. Our concern, in this paper, is to numerically interpret the kerosene oil-based hybrid nanofluids comprising dissimilar nanoparticles like silver (Ag) and manganese zinc ferrite (MnZnFe2O4). A numerical algorithm, which is mainly based on finite difference discretization, is developed to find the numerical solution of the problem. A numerical comparison appraises the efficiency of this algorithm. The effects of physical parameters are examined via the graphical representations in either case of...
Numerical simulations of the hydrodynamic performance of the propeller with wake equalizing duct behind the ship
, Article Scientia Iranica ; Volume 29, Issue 5 B , 2022 , Pages 2332-2348 ; 10263098 (ISSN) ; Bamdadinejad, M ; Ghassemi, H ; Sharif University of Technology
Sharif University of Technology
2022
Abstract
The equalizing wake flow into the propeller behind the ship is important from the hydrodynamic performance viewpoint. In this study, numerical simulations of the DTMB4119 propeller with two symmetric and asymmetric duct types behind the KRISO Container Ship (KCS) are performed using Computational Fluid Dynamics (CFD). In order to improve the wake equaling flow, a combined duct and stators' configurations are installed before the propeller in the stern of the ship and its hydrodynamic performance is studied using CFD. A duct with the NACA4415 section and two types of stator configurations are selected. The STAR-CCM+ software using the finite volume discretization method was used to solve the...
Satellite attitude PDE-based controller design considering fluid fuel sloshing in planar maneuver
, Article Aerospace Science and Technology ; Volume 122 , 2022 ; 12709638 (ISSN) ; Salarieh, H ; Nejat Pishkenari, H ; Sharif University of Technology
Elsevier Masson s.r.l
2022
Abstract
Due to significance of high-accuracy attitude control, the fuel sloshing effects on the satellite attitude should be considered, more precisely. This work deals with the attitude control of a liquid propellant-filled satellite considering the incompressible fuel sloshing in the planar maneuver. The satellite consists of a rigid body, a partially-filled tank and a flexible diaphragm. Hamilton's principle is employed to derive nonlinear coupled PDEs-ODEs governing the coupled satellite-diaphragm propellant tank system. Afterwards, to dispense with the spillover instability, a PDE-based controller is designed to realize the satellite attitude control while tracking a desired pitch angle and...
Multiscale modeling of coupled thermo-hydro-mechanical analysis of heterogeneous porous media
, Article Computer Methods in Applied Mechanics and Engineering ; Volume 391 , 2022 ; 00457825 (ISSN) ; Khoei, A. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This paper presents a numerical multiscale formulation for analysis of the transient heat and fluid flow in deformable heterogeneous porous media. Due to the heterogeneity of the media, the direct numerical simulation of the micro-structures leads to high computational costs. Hence, the multi-scale method can provide an efficient computational procedure. To this end, the first-order computational homogenization is adopted for two-scale simulation of THM problems. The governing equations of the problem contain a stress equilibrium equation, a mass continuity equation and an advection–diffusion equation in a fully coupled manner. Accordingly, the proper virtual power relations are defined as a...
Analytical and numerical biaxial bending analysis of deepwater riser due to vortex-induced vibration
, Article Journal of Marine Science and Technology (Japan) ; Volume 27, Issue 1 , 2022 , Pages 492-507 ; 09484280 (ISSN) ; Komachi, Y ; Sharif University of Technology
Springer Japan
2022
Abstract
Previous studies of analysis and prediction of marine risers responses usually focus on vortex-induced vibration (VIV) of cross-flow (CF) direction rather than in-line (IL). Recent studies show that responses of IL direction tend to dominate in some cases. Responses of long riser due to biaxial bending of IL and CF VIV are investigated. Closed-form formulas are derived for estimating maximum normal stress due to the biaxial moment of CF/IL VIV and relations for estimating biaxial stress using CF values are presented. Analytical results are compared with numerical results of the time domain model and a good correlation is observed. It is shown that for tension and bending-controlled modes of...
Investigating the behavior of cracks in welded zones of supporting structure of spherical pressure vessel under seismic loading
, Article Journal of Constructional Steel Research ; Volume 191 , 2022 ; 0143974X (ISSN) ; Ghazi, M ; Adibnazari, S ; Rofooei, F. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this paper, the numerical studies on the semi-elliptical crack behavior in different locations of welded zones in the supporting structure of a spherical pressure vessel under an earthquake are presented. The cracks in the welded zones of supporting structures under earthquake effects may jeopardize the safety of spherical pressure vessels and result in catastrophic failure. A detailed finite element sub-modeling technique is carried out to compute the mixed-mode stress intensity factors along the crack front. Furthermore, crack behavior with different aspect ratios a/c: 0.25, 0.5, and 0.75 at the weld and the heat-affected zone of the supporting structure is evaluated. The...
Thermal, thermodynamic and exergoeconomic investigation of a parabolic trough collector utilizing nanofluids
, Article Applied Thermal Engineering ; Volume 206 , 2022 ; 13594311 (ISSN) ; Golab, E ; Nasiri Sadr, A ; Vafai, K ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The exploitation of solar energy facilitates the renewable energy paradigm. In this regard, parabolic trough collectors (PTC) are considered as a useful set-up to absorb solar energy. Simultaneous study of thermal, thermodynamic, and exergoeconomic performance of PTC systems paves the way for designers and manufacturers to not only have a better insight into understanding the underlying concepts about the operation of PTC systems but also to find the most effective and cost-effective circumstances. This study aims at analyzing a practical PTC system by considering an evacuated absorber tube with glass cover, non-uniform heat flux, and taking into account the convective and radiative heat...
Investigating the effects of precursor concentration and gelling parameters on droplet-based generation of Ca-Alginate microgels: identifying new stable modes of droplet formation
, Article Materials Today Chemistry ; Volume 24 , 2022 ; 24685194 (ISSN) ; Rezaeian, M ; Mahmoudi, Z ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Droplet-based microfluidics is an attractive approach for producing microgels due to its high potential to control the size and shape of the particles and precisely entrap the substances within the hydrogel matrix. However, the microfluidic generation of monodisperse microgels with desired structures is still challenging. Indeed, the rheological and interfacial properties of the immiscible fluids, as well as the adopted gelling strategy, play important roles in microfluidic methods. Herein, sodium alginate droplets with different concentrations are generated via a microfluidic device with a flow-focusing unit. Besides, a combined in situ and ex situ strategy is optimized to crosslink sodium...
Parametrization of PC-SAFT EoS for solvents reviewed for use in pharmaceutical process design: VLE, LLE, VLLE, and SLE Study
, Article Industrial and Engineering Chemistry Research ; Volume 61, Issue 23 , 2022 , Pages 8252-8268 ; 08885885 (ISSN) ; Asgari, M ; Sharif University of Technology
American Chemical Society
2022
Abstract
The perturbed chain-statistical associating fluid theory equation of state (PC-SAFT EoS) is one of the state-of-the-art thermodynamic models used in the phase equilibrium calculation of associating mixtures, in particular, in the pharmaceutical industry. Accordingly, parametrization of the PC-SAFT EoS for approved solvents reviewed for use in pharmaceutical process design by the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) was done in the present study. First, the PeC-SAFT EoS model parameters for 41 pure solvents were regressed (of 62 solvents). The available high-quality binary vapor-liquid equilibrium (VLE)...
Quantifying lake–aquifer water exchange: the case of Lake Urmia, Iran
, Article Hydrological Sciences Journal ; Volume 67, Issue 5 , 2022 , Pages 725-740 ; 02626667 (ISSN) ; Hosseini, S. M ; Ataie Ashtiani, B ; Nikraftar, Z ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
This study investigated the lake–aquifer hydraulic interactions in Lake Urmia (LU) as the second largest hypersaline lake in the world. Due to the scarcity of hydrogeological data required for modelling, a method based on Darcy’s Law and lake water budget was used to quantify the lake–aquifer interaction. Long-term ground- and satellite-based hydrological datasets over the time frame 2001–2019 were used. Results indicate that the groundwater flux between LU and the aquifers controls 18.74 ± 1.67% of the lake’s water storage. While 10 out of 14 adjacent aquifers recharge LU at a rate of less than 180 m3/m.month, one phreatic aquifer recharges the LU up to 1400 m3/m.month. Two aquifers are...
Micro-plasma actuator mechanisms in interaction with fluid flow for wind energy applications: operational parameters
, Article Engineering with Computers ; 2022 ; 01770667 (ISSN) ; Mazaheri, K ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Plasma actuator is a flow control device which may be used to improve the performance of wind turbine blades at low airspeeds. One of the most robust numerical models to simulate the interaction of the plasma actuator with the fluid flow is the electrostatic model. This model is improved by the authors. Due to the high cost of performing experimental optimization, the optimization of plasma actuators may be investigated by this numerical model. To optimize the aerodynamic performance of a Delft University (DU) wind turbine airfoil in a full stall condition, we used the operational parameters (voltage, frequency and the waveform) applied to the plasma actuator as the main design variables. We...
Magnetic field-induced control of a compound ferrofluid droplet deformation and breakup in shear flow using a hybrid lattice Boltzmann-finite difference method
, Article International Journal of Multiphase Flow ; Volume 146 , 2022 ; 03019322 (ISSN) ; Bijarchi, M. A ; Ghorbanpour Arani, A ; Rahimian, M. H ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The deformation and breakup dynamics of a compound ferrofluid droplet under shear flow and uniform magnetic field are numerically studied in this paper. Utilizing magnetic field provides the possibility to obtain better control over the compound droplet morphology and breakup in a simple shear flow. To solve the governing equations for interfaces motion and hydrodynamics, the conservative phase field lattice Boltzmann model is employed, and a finite difference approach is applied for calculating the magnetic field. To verify the accuracy of present simulations, the results are validated with those of four relevant benchmarks including liquid lens between two stratified fluids, three-phase...