Author: Jaime YeargansPublisher:
ISBN:
Category :
Languages : en
Pages : 96
Book Description
Ultrasonic Wave Speed in Suspensions and Fluidized Beds of Glass Beads
Author: Jaime YeargansStrong Scattering of Ultrasonic Waves in Fluidized Suspensions, Wave Propagation, Spectroscopy Techniques and Particle Dynamics
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
This thesis presents the results of three main experimental projects; a study of ultrasonic wave propagation in strongly scattering materials, the use of the results of this first study to develop new techniques in ultrasonic correlation spectroscopy, and the use of these techniques to measure the dynamics of particles in fluidized beds. The first project involves the investigation of wave propagation in random, inhomogeneous materials that scatter ultrasound strongly (i.e. materials where the scattering mean free path is comparable to the ultrasonic wavelength [lambda]). I have measured the velocities of the weak ballistic pulse that travels through these materials without scattering out of the forward direction. Using the results of this wave propagation study, we have developed two new ultrasonic spectroscopy techniques. Dynamic Sound Scattering (DSS) uses singly scattered sound to measure the rms velocity of scatterers. Diffusing Acoustic Wave Spectroscopy (DAWS) uses multiply scattered sound, describedby the diffusion approximation, to measure the relative motion of scatterers. This thesis explains the underlying principles governing these techniques and the ways that these techniques can be implemented in practice to provide powerful new methods for investigating the dynamics of strongly scattering materials. Using DAWS and DSS, I have investigated the dynamics of particles suspended against sedimentation by a fluid flowing upwards in a fluidized bed. Since ultrasonic wavelengths are on the order of millimeters, the suspensions that can be Probed contain particles with diameters on the millimeter scale; this corresponds to a regime that is of interest in industrial applications. Thus DAWS and DSS are well suited to the high Reynolds number, high volume fraction suspensions to which other current techniques are least suited. In our experiments, the velocity fluctuations and velocity correlation lengths are measured as a function of the volume fraction and sampl.
The Propagation of Ultrasonic Waves in Gas-containing Suspensions
Author: Natalia MorkunPublisher: Cambridge Scholars Publishing
ISBN: 1527524442
Category : Medical
Languages : en
Pages : 142
Book Description
This book presents the results of research in the field of automated systems for the monitoring and control of technological processes of mining production. It offers the first mathematical description of Lamb waves’ propagation processes on surfaces in contact with randomly heterogeneous media (gas-containing suspensions). It is also the first book to explore the analytical dependencies of the attenuation values of Lamb and volume ultrasound waves on the number, size, density, and other characteristics of heterogeneous media during their natural and specially organized movements.
Strong Scattering of Ultrasonic Waves in Fluidized Suspensions
Author: Michael L. CowanUltrasonic Techniques for Fluids Characterization
Author: Malcolm J.W. PoveyPublisher: Elsevier
ISBN: 0080519849
Category : Science
Languages : en
Pages : 229
Book Description
This book is a comprehensive and practical guide to the use of ultrasonic techniques for the characterization of fluids. Focusing on ultrasonic velocimetry, the author covers the basic topics and techniques necessaryfor successful ultrasound measurements on emulsions, dispersions, multiphase media, and viscoelastic/viscoplastic materials. Advanced techniques such as scattering, particle sizing, and automation are also presented. As a handbook for industrial and scientific use, Ultrasonic Techniques for Fluids Characterization is an indispensable guide to chemists and chemical engineers using ultrasound for research or process monitoring in the chemical, food processing, pharmaceutical, cosmetic, biotechnology,and fuels industries. - Appeals to anyone using ultrasound to study fluids - Provides the first detailed description of the ultrasound profiling technique for dispersions - Describes new techniques for measuring phase transitions and nucleation, such as water/ice and oil/fat - Presents the latest ultrasound techniques for particle sizing in concentrated systems - Explains new techniques for compressibility measurements in dispersions and fluids, including cell suspensions - Contains a detailed treatment of ultrasound scattering theory - Written by one of the leading researchers in the field - Includes over 350 references to the primary literature
Absorption and Dispersion of Ultrasonic Waves
Author: Karl F. HerzfeldPublisher: Academic Press
ISBN: 1483275701
Category : Science
Languages : en
Pages : 554
Book Description
Absorption and Dispersion of Ultrasonic Waves focuses on the influence of ultrasonics on molecular processes in liquids and gases, including hydrodynamics, energy exchange, and chemical reactions. The book first offers information on the Stokes-Navier equations of hydrodynamics, as well as equations of motion, viscosity, formal introduction of volume viscosity, and linearized wave equation for a nonviscous fluid. The manuscript then ponders on energy exchange between internal and external degrees of freedom as relaxation phenomenon; effect of slow energy exchange on sound propagation; different ways of evaluating the dispersion curve; and exact calculation of absorption and dispersion. The text examines the effects of chemical reactions, thermodynamic theory of relaxation, and mixtures. The book also evaluates the absorption of high intensity sound waves, ratio of relaxation absorption to classical absorption at maximum, and gas mixtures. Discussions also focus on translational relaxation in monatomic gases, linear triatomic molecules, and results for rotational relaxation. The manuscript is a dependable source of data for readers interested in the absorption and dispersion of ultrasonic waves.
Physical Review
Author: Publisher:
ISBN:
Category : Fluids
Languages : en
Pages : 1748
Book Description
Publishes papers that report results of research in statistical physics, plasmas, fluids, and related interdisciplinary topics. There are sections on (1) methods of statistical physics, (2) classical fluids, (3) liquid crystals, (4) diffusion-limited aggregation, and dendritic growth, (5) biological physics, (6) plasma physics, (7) physics of beams, (8) classical physics, including nonlinear media, and (9) computational physics.
Ultrasonic Velocity and Attenuation in a Glass-bead Percolation System
Author: Norbert George PachetPublisher:
ISBN:
Category :
Languages : en
Pages : 412
Book Description
Fluidization of Small Diameter Glass Beads at Low Mass Velocities
Author: Boni P. MartinezThe Suspension of Spherical Glass Beads in Water
Author: David IsertPublisher:
ISBN:
Category : Fluidization
Languages : en
Pages : 210
Book Description