Loading...
Search for:
flow-measurement
0.004 seconds
Total 40 records
Flow analysis around a pitching airfoil
, Article Collection of Technical Papers - 22nd AIAA Applied Aerodynamics Conference, Providence, RI, 16 August 2004 through 19 August 2004 ; Volume 2 , 2004 , Pages 914-924 ; 10485953 (ISSN) ; Mani, M ; Soltani, M. R ; Boroomand, M ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc
2004
Abstract
A series of low-speed wind tunnel tests were performed to investigate the unsteady pressure distribution over an airfoil. Dynamic pitching motion was produced by oscillating the model over a range of reduced frequencies, k=0.022 - 0.066. In addition, steady data were acquired and examined to furnish as a baseline for analysis and comparison. The model was oscillated between 0-18° angle of attack. Surface static pressure was measured from x/c=5-80% for both upper and lower surfaces. The pressure coefficients in the low angle of attack range showed little overshoot when compared with the static values, while for the large angle of attack cases the differences were significant. For a constant...
Computation of turbulent flow over highly curved configuration using a conventional two-equation turbulence model
, Article 45th AIAA Aerospace Sciences Meeting 2007, Reno, NV, 8 January 2007 through 11 January 2007 ; Volume 9 , 2007 , Pages 6262-6275 ; 1563478900 (ISBN); 9781563478901 (ISBN) ; Taeibi Rahni, M ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc
2007
Abstract
A new procedure for simulating turbulent flow in three-dimensional arbitrary geometries is presented. Finite volume method using physical covariant velocities on a staggered grid arrangement was used in this investigation. This work is an extension of previous successful work to three-dimensional cases. The ability of the new algorithm was tested using a conventional two-equation turbulence model on a highly separated turbulent flow test case. The low Reynolds number k-ω turbulence model of Wilcox was utilized to evaluate its capability in modeling highly curved flows. Turbulent flow over a three-dimensional hill, which is appropriate in assessment of ability of turbulence models in...
Numerical simulation of submerged flows with baffles uSING ν2̄ - F and k-ε turbulence models
, Article 2006 ASME International Mechanical Engineering Congress and Exposition, IMECE2006, Chicago, IL, 5 November 2006 through 10 November 2006 ; 2006 ; 08888116 (ISSN); 0791837904 (ISBN); 9780791837900 (ISBN) ; Firoozabadi, B ; Sherif, S. A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2006
Abstract
This paper introduces the concept of a submerged hydraulic jump being used for energy dissipation. A baffle wall is used to produce a stable deflected surface jet, thereby deflecting the high-velocity supercritical stream away from the bed to the surface. An elliptic relaxation turbulence model (v 2̄ - f model) has been used to simulate this submerged flow. During the last few years, the v2̄ - f turbulence model has become increasingly popular due to its ability to account for near-wall damping without use of damping functions. In addition, it has been proved that the v̄2 - f model is superior to other RANS methods in many fluid flows where complex flow features are present. In this study,...
Design of a Ultrasonic system for a Multi-purpose Production Logging Tool (PLT)
, M.Sc. Thesis Sharif University of Technology ; Movahhedian Attar, Hamid (Supervisor)
Abstract
In the oil industry, a better understanding of the well condition leads to improve the management and increase the oil production. Production logging tools is a set of tools for measuring different parameters such as density, diameter and flow in oil and gas wells. These tools are considered among high-tech tools in the oil industry. The reason is that they should work in harsh conditions, i.e. high temperature about 170 ° C and pressure around 15000 psi, and at the same time give an accurate measurement of the quantity. Current production-logging tools measure the fluid velocity and the diameter of an oil well by individual mechanical tools, and the density by a radioactive densitometer. ...
Production Well Multi-Phase Flow Measurement Using Ultrasonic Technology
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Sahd, Saeed (Supervisor) ; Amjadi, Ahmad (Co-Supervisor)
Abstract
Flow measurement in both types of single phase and multiphase has a crucial place in a wide variety of industries, specially petroleum industry. for single phase flowmeters, improving their precision using different types of mechanical, mathematical and analytical techniques will be considered as an important step. Using multiphase flow meters will cause no need of volume catching and costly separators and also make us capable of taking well-timed decisions in production management. for making flow meters weather multiphase or single phase, there is a crucial need of a multiphase flow loop. To achieve that, an 8-meter-long flow loop using transparent Plexiglas pipes with inside diameter of...
Investigation of the Effects of Wall Roughness on the Acoustic Field for Flow Inside a Pipe
, M.Sc. Thesis Sharif University of Technology ; Taghizadeh Manzari, Mehrdad (Supervisor)
Abstract
One of the methods of measuring the flow rate in a pipe (channel) is by using the acoustic waves with long wavelenghs in Sonar flowmeters. This flowmeter consists of an array of sensors, mounted on the outer wall of the pipe. These sensors by listening and interpreting the sound waves passing through the fluid, would give a “non-intrusive” measurement of the volumetric flow rate. This means that the flowmeter is not in direct contact with the flow and therefore its repair, relocation or replacement will not disturb the flow. In this project, we will provide a clear understanding of the principles and physics involved in sonar-based acoustic flowmeters, by means of numerical simulation of the...
Transient conduction prediction in nozzle assembly of solid rocket motors
, Article 45th AIAA Aerospace Sciences Meeting 2007, Reno, NV, 8 January 2007 through 11 January 2007 ; Volume 4 , 2007 , Pages 2333-2337 ; 1563478900 (ISBN); 9781563478901 (ISBN) ; Tahsini, A. M ; Sharif University of Technology
2007
Abstract
Transient heat-up of a solid propellant rocket structure during motor burning time is studied, numerically. The solid phase energy equation coupled with unsteady compressible flow equations are used in this simulation. The flow-field equations are discretized and solved using upwind Roe's scheme. The results show that heat transfer from the gas phase boundaries has negligible effect on internal ballistics behavior. On the other hand, the results are suitable for a thermal stresses analysis in the chamber case and are consequently valuable from structural design viewpoints
Numerical simulation of three-dimensional interfacial flows
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 17, Issue 4 , 2007 , Pages 384-404 ; 09615539 (ISSN) ; Panahi, R ; Seif, M. S ; Sharif University of Technology
2007
Abstract
Purpose - This study aims to present compatible computational fluid dynamics procedure for calculation of incompressible three-dimensional time-dependent flow with complicated free surface deformation. A computer software is developed and validated using a variety of academic test cases. Design/methodology/approach - Two fluids are modeled as a single continuum with a fluid property jump at the interface by solving a scalar transport equation for volume fraction. In conjunction, the conservation equations for mass and momentum are solved using fractional step method. Here, a finite volume discretisation and colocated arrangement are used. Findings - The developed code results in accurate...
Determination of environmental water requirements of Lake Urmia, Iran: An ecological approach
, Article International Journal of Environmental Studies ; Volume 64, Issue 2 , 2007 , Pages 161-169 ; 00207233 (ISSN) ; Nazaridoust, A ; Sharif University of Technology
2007
Abstract
Lake Urmia is a thalassohaline ecosystem. It is an extremely simple ecological pyramid. This makes it a very sensitive ecosystem. This ecosystem has been facing various threats regarding the amount of water released from the associated basin. To calculate the lake water requirement with an ecological approach, we identified three variables: ecology, water quality, and water quantity indices as environmental indicators. The ecological index represented by Artemia urmiana is considered as an independent variable; while, the water quality index represented by concentration of NaCl, and the water quantity index represented by water elevation are regarded as dependent variables. The salinity...
Two-dimensional numerical solution of steady withdrawal from the lens of freshwater in a tropical Island
, Article 2006 ASME Joint U.S.- European Fluids Engineering Division Summer Meeting, FEDSM2006, Miami, FL, 17 July 2006 through 20 July 2006 ; Volume 1 SYMPOSIA , 2006 , Pages 627-633 ; 0791847500 (ISBN); 9780791847503 (ISBN) ; Mohammadi, M. H ; Saeedpanah, I ; Sharif University of Technology
American Society of Mechanical Engineers
2006
Abstract
The work presented here is a study of the steady withdrawal of water from the lens of freshwater situated above the ocean's salt water and within the island. It is the aim of this paper to investigate the process of withdrawal from the lens of freshwater with a view to establishing the critical flow values for withdrawal and the effects of sink location and density differences on these values, and also to determine the effects of relative density differences.Steady solutions are found for the shape of the interface between salt and freshwater beneath a tropical island. A Green_s function approach is used and proves to be much more robust than spectral methods. Computations of the surface...
Flow measurements around a long axisymmetric body with varying cross section
, Article 43rd AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, 10 January 2005 through 13 January 2005 ; 2005 , Pages 7221-7233 ; Taeibi Rahni, M ; Farahani, M ; Heidari, M. R ; Sharif University of Technology
2005
Abstract
Supersonic flow over tapered bodies of revolution is investigated using both experimental and numerical methods. The experimental study consisted of a series of wind tunnel tests on an ogive-cylinder body and included the surface static pressure and boundary layer profiles measurements, at various angles of attack. Further, the flow around the model was visualized using Schlieren technique. All tests were conducted in the trisonic wind tunnel of Qadr Research Center, Iran. Static surface pressure results show that the circumferential pressure at different nose sections vary significantly with angles of attack, in contrast to the circumferential pressure signatures along the cylindrical part...
Model-based analysis for kinetic complexation study of Pizda and Cu(II)
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 70, Issue 3 , August , 2008 , Pages 674-681 ; 13861425 (ISSN) ; Maeder, M ; Jalali Heravi, M ; Norman, S. E ; Sharif University of Technology
2008
Abstract
In the present work, the multivariate kinetic complexation of a new synthesized ligand, 1-(2″-hydroxyl cyclohexyl)-3′-[aminopropyl]-4-[3′-aminopropyl]piperazine (Pizda) and Cu2+ in 50% ethanol-water solution is investigated using the UV-vis stopped-flow technique and state-of-the-art multi-wavelength numerical analysis. Model-based least squares fitting analysis or hard modeling is a specific part of chemometrics which is based on mathematical relationships for describing the measurements. Some recent developments include the incorporation of the effects of non-ideal experimental conditions into the fitting algorithm so it can substantially simplify experimental procedures. In this study no...
Thermal transport characteristics of non-newtonian electroosmotic flow in a slit microchannel
, Article ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, ICNMM 2011, 19 June 2011 through 22 June 2011 ; Volume 1 , June , 2011 , Pages 169-176 ; 9780791844632 (ISBN) ; Sadeghi, A ; Saidi, M. H ; Sharif University of Technology
2011
Abstract
Electroosmosis has many applications in fluid delivery at microscale, sample collection, detection, mixing and separation of various biological and chemical species. In biological applications, most fluids are known to be non-Newtonian. Therefore, the study of thermal features of non-Newtonian electroosmotic flow is of great importance for scientific communities. In the present work, the fully developed electroosmotic flow of power-law fluids in a slit microchannel is investigated. The related equations are transformed into non-dimensional forms and necessary changes are made to adapt them for non-Newtonian fluids of power-law model. Results show that depending on different flow parameters...
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...
DPD simulation of non-Newtonian electroosmotic fluid flow in nanochannel
, Article Molecular Simulation ; Volume 44, Issue 17 , 2018 , Pages 1444-1453 ; 08927022 (ISSN) ; Zakeri, R ; Darbandi, M ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
We use the dissipative particle dynamics (DPD) method to simulate the non-Newtonian electroosmotic flow (EOF) through nanochannels. Contrary to a large amount of past computational efforts dedicated to the study of EOF profile, this work pays attention to the EOF of non-Newtonian fluids, which has been rarely touched in past publications. Practically, there are many MEMS/NEMS devices, in which the EOF behaviour should be treated assuming both non-continuum and non-Newtonian conditions. Therefore, our concern in this work is to simulate the EOF through nanochannels considering both non-Newtonian fluid properties and non-continuum flow conditions. We have chosen DPD as our working tool because...
A high-order accurate unstructured spectral difference lattice Boltzmann method for computing inviscid and viscous compressible flows
, Article Aerospace Science and Technology ; Volume 98 , 2020 ; Ghaffarian, A ; Sharif University of Technology
Elsevier Masson SAS
2020
Abstract
In the present work, the spectral difference lattice Boltzmann method (SDLBM) is implemented on unstructured meshes for the solution methodology to be capable of accurately simulating the compressible flows over complex geometries. Both the inviscid and viscous compressible flows are computed by applying the unstructured SDLBM. The compressible form of the discrete Boltzmann–BGK equation with the Watari model is considered and the solution of the resulting system of equations is obtained by applying the spectral difference method on arbitrary quadrilateral meshes. The accuracy and robustness of the unstructured SDLBM for simulating the compressible flows are demonstrated by simulating four...
Observability enhancement by optimal PMU placement considering random power system outages
, Article Energy Systems ; Vol. 2, issue. 1 , 2011 , p. 45-65 ; ISSN: 18683967 ; Fotuhi-Firuzabad, M ; Shahidehpour, M ; Khodaei, A ; Sharif University of Technology
Abstract
This paper enhances the observability of power networks by taking into consideration random component outages. The architecture of wide-area measurement system (WAMS) is analyzed in order to identify components that would affect the network observability. An iterative framework is devised to calculate a bus index in power networks equipped with phasor measurement units (PMUs) and conventional measurements. The average of bus indices represents a system index which provides an overall insight on the power network observability. The system index is utilized as a criterion to distinguish among multiple optimal PMU placements. Conventional bus injection and line flow measurements and the effect...
Observability enhancement by optimal PMU placement considering random power system outages
, Article Energy Systems ; Volume 2, Issue 1 , 2011 , Pages 45-65 ; 18683967 (ISSN) ; Fotuhi Firuzabad, M ; Shahidehpour, M ; Khodaei, A ; Sharif University of Technology
Abstract
This paper enhances the observability of power networks by taking into consideration random component outages. The architecture of wide-area measurement system (WAMS) is analyzed in order to identify components that would affect the network observability. An iterative framework is devised to calculate a bus index in power networks equipped with phasor measurement units (PMUs) and conventional measurements. The average of bus indices represents a system index which provides an overall insight on the power network observability. The system index is utilized as a criterion to distinguish among multiple optimal PMU placements. Conventional bus injection and line flow measurements and the effect...
Effect of a standing baffle on the flow structure in a rectangular open channel
, Article Journal of Hydraulic Research ; Volume 48, Issue 3 , Jun , 2010 , Pages 400-404 ; 00221686 (ISSN) ; Takeda, Y ; Firoozabadi, B ; Sharif University of Technology
2010
Abstract
The effect of an intermediate standing baffle on the flow structure in a rectangular open channel has been investigated by a three-dimensional acoustic Doppler velocimeter. Investigation of time-averaged velocity profiles at different streamwise positions reveals that the approach flow is fully developed upstream of the baffle. By analysing the space-averaged power spectra of streamwise velocity, a peak structure was observed in the upstream baffle region. Downstream of the baffle this peak structure has been alleviated by the baffle. The same analysis for the vertical component indicates the existence of a peak structure both up- and downstream of the baffle. Consequently, a baffle affects...
A non-iterative approach for AC state estimation using line flow based model
, Article International Journal of Electrical Power and Energy Systems ; Volume 43, Issue 1 , 2012 , pages 1413-1420 ; 1420615 (ISSN) ; Fotuhi Firuzabad, M ; Aminifar, F ; Sharif University of Technology
Abstract
One of the underlying requirements in the present energy management systems (EMSs) is to have a complete understanding of the system status. This feature is realized via state estimation (SE) engine. This paper presents a new and efficient SE approach which leads to a desirable outcome using a non-iterative calculation. The proposed model is based on a new AC power flow formulation designated as the line flow based (LFB) model. The objective function is to minimize the weighted least square of measurement residuals. The developed method adopts the line flows and square of voltage magnitudes as the problem state variables and incorporates both active and reactive power quantities. The...