Author: Publisher:
ISBN:
Category : Fluid dynamic measurements
Languages : en
Pages : 40
Book Description
Measurement of Velocities in Gas-liquid Two-phase Flow Using Laser Doppler Velocimetry
Author: Publisher:
ISBN:
Category : Fluid dynamic measurements
Languages : en
Pages : 40
Book Description
Investigation of Simultaneous Measurement of Particle Size and Velocity in Gas-particle Two-phase Flow Using a Laser-Doppler Velocimeter
Author: Dana Gene AndrewsPublisher:
ISBN:
Category : Laser Doppler velocimeter
Languages : en
Pages : 154
Book Description
Laser Velocimetry in Fluid Mechanics
Author: Alain BoutierPublisher: John Wiley & Sons
ISBN: 1118569334
Category : Science
Languages : en
Pages : 436
Book Description
In fluid mechanics, velocity measurement is fundamental in order to improve the behavior knowledge of the flow. Velocity maps help us to understand the mean flow structure and its fluctuations, in order to further validate codes. Laser velocimetry is an optical technique for velocity measurements; it is based on light scattering by tiny particles assumed to follow the flow, which allows the local fluid flow velocity and its fluctuations to be determined. It is a widely used non-intrusive technique to measure velocities in fluid flows, either locally or in a map. This book presents the various techniques of laser velocimetry, as well as their specific qualities: local measurements or in plane maps, mean or instantaneous values, 3D measurements. Flow seeding with particles is described with currently used products, as well as the appropriate aerosol generators. Post-processing of data allows us to extract synthetic information from measurements and to perform comparisons with results issued from CFD codes. The principles and characteristics of the different available techniques, all based on the scattering of light by tiny particles embedded in the flow, are described in detail; showing how they deliver different information, either locally or in a map, mean values and turbulence characteristics.
Measuring Techniques in Gas-liquid Two-phase Flows
Author: J. M. DelhayePublisher: Springer
ISBN:
Category : Science
Languages : en
Pages : 780
Book Description
Laser Doppler Measurements of Droplet Size and Velocity in a Vertical Upward Gas-liquid Annualar Two-phase Flow
Author: Jamaluddin Md. SherriffLaser Doppler Measurements of Droplet Size and Velocity in a Vertical Upward Gas-liquid Annular Two-phase Flow
Author: Jamaluddin Md SheriffPublisher:
ISBN:
Category :
Languages : en
Pages : 482
Book Description
Application of a Laser-doppler Technique to the Measurement of Particle Velocity in Gas-particle Two-phase Flow
Author: Stanford University. Department of Aeronautics and AstronauticsPublisher:
ISBN:
Category :
Languages : en
Pages : 362
Book Description
In chemical propulsion, the use of metallic fuel constituents burning to particulate refractory oxides in rocket engines has forced attention to the understanding of two-phase nozzle expansion processes. In this study light from a helium-neon laser was reflected both from a fixed target and from moving particles. A lens concentrated the laser light and the light back-scattered from the particles was picked up by the same lens and directed into a Fabry-Perot scanning plate interferometer. The interferometer limited observation at any moment to those particles whose Doppler shifted frequency coincided with the interferometer transmission frequency. The light from the fixed target provided a frequency reference system, and calibrated movement of the interferometer mirror spacing provided continuous examination of velocity. Data in the form of lightscattering and number count vs velocity has been obtained for water droplets in subsonic flow, for aluminum spheres and alumina abrasive in cold supersonic flow and for aluminum and magnesium oxide in hot supersonic flow. Number count-velocity data was found to be a complicated function of particle size distribution and vector velocity distribution as well as instrument characteristics.
A Laser Doppler Velocimeter for Measurement of Flows Induced by Flames Propagating Over Condensed Fuels
Author: R. J. SantoroPublisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
The primary process in the spread of fire along the surface of a condensed fuel is heat transfer from the burning region of the fuel to the material ahead of the flame. In the early stages of a fire, the two mechanisms by which this heat transfer occurs are conduction and convection ahead of the flame through the gas and fuel phases. The determination of the importance of the convective heat transfer can be ascertained only by accurate measurement of the fluid flow velocity and temperature fields near the flame front. Convective flows induced by spreading flames are characterized by low fluid velocities with changes in magnitude and direction accompanied by sharp temperature changes occurring over small distances. The bulk gas velocity induced by the flame frequently opposes the propagation. In liquids, there exists, as well, a liquid motion in the direction of the propagation of the flame. These characteristics make quantitative measurements of fluid velocities difficult using conventional techniques. With the advent of Laser Doppler Velocimeter (LDV) techniques, a non-perturbing means of making high resolution measurements of two-dimensional low velocity fields now exists. Thus, the possibility of determining the role of convective effects has become realizable.
Initial Discussion of the Application of a Laser-doppler Technique to the Measurement of Particle Velocity in Gas-particle Two-phase Flow
Author: Stanford University. Department of Aeronautics and AstronauticsPublisher:
ISBN:
Category : Doppler effect
Languages : en
Pages : 186
Book Description
Measuring Techniques in Gas-Liquid Two-Phase Flows
Author: J.M. DelhayePublisher: Springer Science & Business Media
ISBN: 364282112X
Category : Science
Languages : en
Pages : 756
Book Description
A IUTAM symposium on "Measuring Techniques in Gas-Liquid Two Phase Flows" was held on July 5-8, 1983 in Nancy, France. This topic in cluded instrumentation for steam-water and liquid-vapor flows but strictly excluded measuring techniques for gas or liquid flows with solid particles. The top priority in the paper selection was given to presentations of new methods which had been substantiated by theoretical modeling, calibration tests and comparison tests with other techniques. Examples of experimental resul ts obtained with the proposed instrumentation had to be displayed. However the interpretation of these results in terms of two-phase flow or heat transfer modeling did not fall wi thin the scope of the meeting. Thirty four papers were presented during the Symposium and 79 participants coming from Canada, European countries, Japan and the United States attended the sessions. They represented not only Universities but also state agencies and private companies. After the meeting each paper was peer-reviewed by at least three referees. The Editors of this Procee dings Volume are pleased to extend their deep gratitude to the following reviewers: J.L. Achard, R.J. Adrian, B. Azzopardi, J.A. Boure, G. Costigan, M. Courtaud, A.E. Dukler, F. Durst, J.R. Fincke, G. Gouesbet, P. Griffith, T.J. Hanratty, A. Hawighorst, T.R. Heidrick, G. Hetsroni, Y.Y. Hsu, M.