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Friction reduction of Al2O3, SiO2, and TiO2 nanoparticles added to non-Newtonian water based mud in a rotating medium
, Article Journal of Petroleum Science and Engineering ; Volume 217 , 2022 ; 09204105 (ISSN) ; Sedaghat, A ; Rashidi, M ; Sabati, M ; Vaidyan, K ; Ali, N ; Omar, M. A. A ; Hosseini Dehshiri, S. S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In drilling industry, energy consumption counts from 20 to 40 percent of total costs. Enhanced water-based mud (WBM) drilling fluids with nanoparticles can save energy in drilling processes. An in-house Taylor-Couette flow system (TCS) was developed at Australian University (AU) to study WBM enhanced by Al2O3, SiO2, and TiO2 nanoparticles. The TCS is really a practical tool to help well drillers with a rough idea of viscosity when nanoparticles are added. The TCS for sure cannot substitute advanced rheometry. The goal of the present experiment is to produce a rough estimate in field operation. Experimental results were examined with several rheology models in our previous publications. In...
New insight into hydrodynamic and cake erosion mechanism during rotating-disk dynamic microfiltration of concentrated bentonite suspensions at different salinity conditions
, Article Separation and Purification Technology ; Volume 300 , 2022 ; 13835866 (ISSN) ; Jamshidi, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The present study investigates the dynamic filtration of concentrated slurry fluids containing colloidal clay particles under different salinity, shear flow, and flux rate conditions. The dynamic filtration study was carried out by the filtration cell equipped with a rotating disk to apply shear stress over the membrane surface. A 3D CFD simulation has been implemented to model the hydrodynamic flows inside the filtration cell to obtain the wall shear stress (WSS) on the membrane surface at different disk rotation speeds. The thickness and surface patterns of fouling were captured utilizing a surface profilometer. First, the cake-filtration model was used to predict the flux rate and fouling...
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
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...
On the yield stress of magnetorheological fluids
, Article Chemical Engineering Science ; Volume 256 , 2022 ; 00092509 (ISSN) ; Alaghehband, N ; Bavil, P. K ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Magnetorheological fluids (MRFs) are a category of functional materials that exhibit magneto-mechanical coupling. These materials exhibit a reversible and instantaneous change from a free-flowing Newtonian fluid to a semi-solid state upon application of a magnetic field. In contrast to ordinary fluids, MRFs can tolerate shear stresses up to a yield value in the presence of a magnetic field. The yield stress strongly depends on intensity of the applied magnetic field and volume fraction of magnetic particles. As the yield stress is the most important parameter of an MRF and must be considered in the design of MR devices, in this work, effects of magnetic field and volume fraction of particles...
The validity and inter-rater reliability of a video-based posture-matching tool to estimate cumulative loads on the lower back
, Article Journal of Biomedical Physics and Engineering ; Volume 12, Issue 4 , 2022 , Pages 417-430 ; 22517200 (ISSN) ; Abdoli Eramaki, M ; Arjmand, N ; Abouhossein, A ; Zakerian, S. A ; Sharif University of Technology
Shriaz University of Medical Sciences
2022
Abstract
Background: Low back pain (LBP) is known as one of the most common workrelated musculoskeletal disorders. Spinal cumulative loads (CLs) during manual material handling (MMH) tasks are the main risk factors for LBP. However, there is no valid and reliable quantitative lifting analysis tool available for quantifying CLs among Iranian workers performing MMH tasks. Objective: This study aimed to investigate the validity and inter-rater reliability of a posture-matching load assessment tool (PLAT) for estimating the L5-S1 static cumulative compression (CC) and shear (CS) loads based on predictive regression equations. Material and Methods: This experimental study was conducted among six...
Unraveling cancer metastatic cascade using microfluidics-based technologies
, Article Biophysical Reviews ; Volume 14, Issue 2 , 2022 , Pages 517-543 ; 18672450 (ISSN) ; Kermanshah, L ; Abouali, H ; Hashemi, H. M ; Yari, A ; Khorasheh, F ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Cancer has long been a leading cause of death. The primary tumor, however, is not the main cause of death in more than 90% of cases. It is the complex process of metastasis that makes cancer deadly. The invasion metastasis cascade is the multi-step biological process of cancer cell dissemination to distant organ sites and adaptation to the new microenvironment site. Unraveling the metastasis process can provide great insight into cancer death prevention or even treatment. Microfluidics is a promising platform, that provides a wide range of applications in metastasis-related investigations. Cell culture microfluidic technologies for in vitro modeling of cancer tissues with fluid flow and the...
A novel formulation of simvastatin nanoemulsion gel for infected wound therapy: In vitro and in vivo assessment
, Article Journal of Drug Delivery Science and Technology ; Volume 72 , 2022 ; 17732247 (ISSN) ; Ghaffari, A ; Keramati, M ; Ahmadi, S ; Dizaji, S ; Moayer, F ; Akbarzadeh, I ; Abazari, M ; razzaghi abyaneh, M ; Bakhshandeh, H ; Sharif University of Technology
Editions de Sante
2022
Abstract
Simvastatin, a well-known antihyperlipidemic drug, has antibacterial activity against a broad range of bacteria, especially Staphylococcus aureus. In present study, a nanoemulsion gel-based formulation containing Simvastatin was developed for infected wound therapy. Therefore, different formulations of Simvastatin nanoemulsion were prepared. Based on droplet size, polydispersity index and zeta potential, the best nanoemulsion formulation containing Simvastatin was selected for development of nanoemulsion gel formulation of drug using carbomer 934 as gelling agent. Thermodynamic stability of Simvastatin nanoemulsion was assessed at different conditions. The in vitro antibacterial activity...
Investigation of coronary artery tortuosity with atherosclerosis: A study on predicting plaque rupture and progression
, Article International Journal of Mechanical Sciences ; Volume 223 , 2022 ; 00207403 (ISSN) ; Fallah, F ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study investigated the effects of different patterns of coronary artery tortuosity (CAT) on the stress concentration of the plaques and the blood flow pattern inside an atherosclerotic artery to predict the risk of plaque rupture and progression. Four different loadings of the coronary artery, including pulsatile blood pressure as well as one-end twist around the artery axis at blood pressures of 74, 100, and 120 mmHg were considered. No study has addressed bent and twist buckling of an atherosclerotic artery considering pulsatile flow (for bent buckling), fluid-solid interaction, and different geometrical parameters of the plaque. The results showed that C-shape tortuosity under...
Patient-specific fluid–structure interaction simulation of the LAD-ITA bypass graft for moderate and severe stenosis: A doubt on the fractional flow reserve-based decision
, Article Biocybernetics and Biomedical Engineering ; Volume 42, Issue 1 , 2022 , Pages 143-157 ; 02085216 (ISSN) ; Firoozabadi, B ; Pakravan, H. A ; Ahmadi Tafti, S. H ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Fractional flow reserve (FFR)-based decision improves the outcomes of percutaneous coronary intervention (PCI) for some patients, while its effectiveness in improving the results of coronary artery bypass graft (CABG) is unclear, in particular for moderate stenosis. It may be due to the fact that FFR cannot take into account the impacts of competitive flow (CF), intimal hyperplasia (IH), as well as compliance mismatch (CMM). As a result, two questions arise 1) whether FFR is a sufficient factor to decide to perform the CABG for patients with moderate to severe stenosis or not and 2) whether post-operative FFR shows the effectiveness of a graft. To shed light on this matter, two...
Numerical-Experimental geometric optimization of the Ahmed body and analyzing boundary layer profiles
, Article Journal of Optimization Theory and Applications ; Volume 192, Issue 1 , 2022 ; 00223239 (ISSN) ; Mashhadian, A ; Amiri, S ; Esfahanian, V ; Afshin, H ; Sharif University of Technology
Springer
2022
Abstract
The trade-off between the fuel consumption and drag coefficient makes the investigations of drag reduction of utmost importance. In this paper, the rear-end shape optimization of Ahmed body is performed. Before changing the geometry, to identify the suitable simulation method and validate it, the standard Ahmed body is simulated using k − ω shear stress transport (SST) and k-epsilon turbulence models. The slant angle, rear box angle, and rear box length as variables were optimized simultaneously. Optimizations conducted by genetic algorithm (GA) and particle swarm optimization (PSO) methods indicate a 26.3% decrease in the drag coefficient. To ensure the validity of the results, a...
Mechanical response of single and double-helix SMA wire ropes
, Article Mechanics of Advanced Materials and Structures ; Volume 29, Issue 26 , 2022 , Pages 5393-5406 ; 15376494 (ISSN) ; Arghavani, J ; Choi, E ; Ostadrahimi, A ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In this paper, based on three-dimensional phenomenological model and using a user-defined material subroutine mechanical behavior of shape memory alloy (SMA) wire ropes (or cables) and their components have been studied through implicit solution method in Abaqus software. Material parameters have been extracted using available experimental data and numerical simulations. Due to the convoluted geometry and interwire contact status within a cable, a finite element analysis is firstly performed for a 1 × 37 steel wire rope to validate modeling and mechanical interactions of a wire rope. Afterwards, superelastic and shape memory effect cables with different constructions (7 × 7 and 1 × 27) are...
Aortic dissection is determined by specific shape and hemodynamic interactions
, Article Annals of Biomedical Engineering ; Volume 50, Issue 12 , 2022 , Pages 1771-1786 ; 00906964 (ISSN) ; Marlevi, D ; Bruse, J. L ; Nezami, F. R ; Moradi, H ; Fortunato, R. N ; Maiti, S ; Billaud, M ; Edelman, E. R ; Gleason, T. G ; Sharif University of Technology
Springer
2022
Abstract
The aim of this study was to determine whether specific three-dimensional aortic shape features, extracted via statistical shape analysis (SSA), correlate with the development of thoracic ascending aortic dissection (TAAD) risk and associated aortic hemodynamics. Thirty-one patients followed prospectively with ascending thoracic aortic aneurysm (ATAA), who either did (12 patients) or did not (19 patients) develop TAAD, were included in the study, with aortic arch geometries extracted from computed tomographic angiography (CTA) imaging. Arch geometries were analyzed with SSA, and unsupervised and supervised (linked to dissection outcome) shape features were extracted with principal component...
Atheroprone sites of coronary artery bifurcation: Effect of heart motion on hemodynamics-dependent monocytes deposition
, Article Computers in Biology and Medicine ; Volume 133 , 2021 ; 00104825 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Atherosclerosis as a common cardiovascular disease is a result of both adverse hemodynamics conditions and monocyte deposition within coronary arteries. It is known that the adhesion of monocytes on the arterial wall and their interaction with the vascular surface are one of the main parameters in the initiation and progression of atherosclerosis. In this work, hemodynamic parameters and monocyte deposition have been investigated in a 3D computational model of the Left Anterior Descending coronary artery (LAD) and its first diagonal branch (D1) under the heart motion. A one-way Lagrangian approach is performed to trace the monocyte particles under different blood flow regimes and heart motion...
An analytical method for spiral-wound heat exchanger: design and cost estimation considering temperature-dependent fluid properties
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 31, Issue 1 , 2021 , Pages 471-496 ; 09615539 (ISSN) ; Mostafazade Abolmaali, A ; Afshin, H ; Sharif University of Technology
Emerald Group Holdings Ltd
2021
Abstract
Purpose: Spiral-wound heat exchangers (SWHEs) are widely used in different industries. In special applications, such as cryogenic (HEs), fluid properties may significantly depend on fluid temperature. This paper aims to present an analytical method for design and rating of SWHEs considering variable fluid properties with consistent shell geometry and single-phase fluid. Design/methodology/approach: To consider variations of fluid properties, the HE is divided into identical segments, and the fluid properties are assumed to be constant in each segment. Validation of the analytical method is accomplished by using three-dimensional numerical simulation with shear stress transport k-ω model, and...
A novel procedure for micromechanical characterization of white matter constituents at various strain rates
, Article Scientia Iranica ; Volume 27, Issue 2 , 2021 , Pages 784-794 ; 10263098 (ISSN) ; Farahmand, F ; Ahmadian, M. T ; Sharif University of Technology
Sharif University of Technology
2021
Abstract
Optimal hyperplastic coeficients of the micromechanical constituents of the human brain stem were investigated. An evolutionary optimization algorithm was combined with a Finite Element (FE) model of a Representative Volume Element (RVE) to nd the optimal material properties of axon and Extra Cellular Matrix (ECM). The tension and compression test results of a previously published experiment were used for optimizing the material coeficients, and the shear experiment was used for the validation of the resulting constitutive model. The optimization algorithm was used to search for optimal shear moduli and ber sti ness of axon and ECM by tting the average stress in the axonal direction with the...
Electrowetting induced droplet generation in T-junctions
, Article Journal of Heat Transfer ; Volume 143, Issue 5 , 2021 ; 00221481 (ISSN) ; Moosavi, A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2021
Abstract
In this study, droplet generation in a T-junction fluidic channel device was studied by using electrowetting actuation with the consideration of different droplet forming regimes. For this purpose, the finite element method (FEM) was used to solve the unsteady Naiver-Stokes equation. In addition, the level set method was applied to capture the interface between two phases. It was shown that there was a good agreement between obtained data and other work during the process of droplet generation in the absence of electrowetting actuation which results in the decrease in the size of the droplet with increasing the velocity ratios. In the shearing regime, the effectiveness of electrowetting on...
Colloidal particle reaction and aggregation control in the Electrohydrodynamic 3D printing technology
, Article International Journal of Mechanical Sciences ; Volume 195 , 2021 ; 00207403 (ISSN) ; Movahhedy, M. R ; Khodaygan, S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
The electrohydrodynamic (EHD) 3D printing technology is an Additive Manufacturing (AM) method that can be used in the manufacture of submicron-size structures. In this process, which is based on the formation of Taylor jet from a metallic ink, the investigation of particles reaction and aggregate formation in ink during printing is of great importance. In this paper, a new Finite Element model based on particle tracing in fluids is presented that couples the different physics that govern an EHD phenomenon. Vortex flow caused by boundary shear stress was observed in the ink jet; which was more like the Marangoni phenomenon in a stationary drop. By experimentally validating the presented model...
A validated reduced-order dynamic model of nitric oxide regulation in coronary arteries
, Article Computers in Biology and Medicine ; Volume 139 , 2021 ; 00104825 (ISSN) ; Tajeddini, F ; Pakravan, H. A ; Mahzoon, M ; Azadi Yazdi, E ; Bazrafshan Drissi, H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Nitric Oxide (NO) provides myocardial oxygen demands of the heart during exercise and cardiac pacing and also prevents cardiovascular diseases such as atherosclerosis and platelet adhesion and aggregation. However, the direct in vivo measurement of NO in coronary arteries is still challenging. To address this matter, a mathematical model of dynamic changes of calcium and NO concentration in the coronary artery was developed for the first time. The model is able to simulate the effect of NO release in coronary arteries and its impact on the hemodynamics of the coronary arterial tree and also to investigate the vasodilation effects of arteries during cardiac pacing. For these purposes, flow...
Prediction of the bending and out-of-plane loading effects on formability response of the steel sheets
, Article Archives of Civil and Mechanical Engineering ; Volume 21, Issue 2 , 2021 ; 16449665 (ISSN) ; Chen, S ; Darabi, R ; Ghabussi, A ; Habibi, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
Failure in sheet metal forming can occur by necking, fracture or wrinkling. By using a forming limit diagram (FLD) as a powerful tool to prevent sheets metal failures in the forming process, provides parameters controlling throughout forming. There are different developed methods for predicting FLDs, which estimate sheet metal forming strains limits. Assessment of FLD estimation reveals that there is a dependency between the effect of several factors containing normal stress, shear stress, sheet thickness, mechanical properties, metallurgical properties, yield function, strain path, and bending with formability. In this research, the effects of bending via two finite element models are...