Multi-Component Acoustic Characterization of Porous Media

Multi-Component Acoustic Characterization of Porous Media

The feasibility to extract porous medium parameters from acoustic recordings is investigated. The thesis gives an excellent discussion of our basic understanding of different wave modes, using a full-waveform and multi-component approach. Focus lies on the dependency on porosity and permeability where especially the latter is difficult to estimate. In this thesis, this sensitivity is shown for interface-wave and reflected-wave modes. For each of the pseudo-Rayleigh and pseudo-Stoneley interface waves unique estimates for permeability and porosity can be obtained when impedance and attenuation are combined. The pseudo-Stoneley wave is most sensitive to permeability: both the impedance and the attenuation are controlled by the fluid flow. Also from reflected-wave modes unique estimates for permeability and porosity can be obtained when the reflection coefficients of different reflected modes are combined. In this case the sensitivity to permeability is caused by subsurface heterogeneities generating mesoscopic fluid flow at seismic frequencies. The results of this thesis suggest that estimation of in-situ permeability is feasible, provided detection is carried out with multi-component measurements. The results of this thesis argely affect geotechnical and reservoir engineering practices.

Multi-Component Acoustic Characterization of Porous Media

Ultrasonic Doppler Velocity Profiler for Fluid Flow

Ultrasonic Doppler Velocity Profiler for Fluid Flow

The ultrasonic velocity profile (UVP) method, first developed in medical engineering, is now widely used in clinical settings. The fluid mechanical basis of UVP was established in investigations by the author and his colleagues with work demonstrating that UVP is a powerful new tool in experimental fluid mechanics. There are diverse examples, ranging from problems in fundamental fluid dynamics to applied problems in mechanical, chemical, nuclear, and environmental engineering. In all these problems, the methodological principle in fluid mechanics was converted from point measurements to spatio-temporal measurements along a line. This book is the first monograph on UVP that offers comprehensive information about the method, its principles, its practice, and applied examples, and which serves both current and new users. Current users can confirm that their application configurations are correct, which will help them to improve the configurations so as to make them more efficient and effective. New users will become familiar with the method, to design applications on a physically correct basis for performing measurements accurately. Additionally, the appendix provides necessary practical information, such as acoustic properties.

Ultrasonic Doppler Velocity Profiler for Fluid Flow

Inverse Problems in Underwater Acoustics

Inverse Problems in Underwater Acoustics

Inverse problems have a long history in acoustics, optics, electromagnetics and geophysics, but only recently have the signals provided by ocean acoustic sensors become numerous and sophisticated enough to allow for realistic identification of the ocean parameters. Acoustic signals propagating for long distances in the water column and reflections of underwater sound from the ocean boundaries provide novel problems of interpretation and inversion. The chapters in this volume discuss some of the contemporary aspects of these problems. They provide recent and useful results for bottom recognition, inverse scattering in acoustic wave guides, and ocean acoustic tomography, as well as a discussion of some of the new algorithms, such as those related to matched-field processing, that have recently been used for inverting experimental data. Each chapter is by a noted expert in the field and represents the state of the art. The chapters have all been edited to provide a uniform format and level of presentation.

Inverse Problems in Underwater Acoustics

Optical, Acoustic, Magnetic and Mechanical Sensor Technologies

Optical, Acoustic, Magnetic and Mechanical Sensor Technologies

Light on physics and math, with a heavy focus on practical applications, Optical, Acoustic, Magnetic, and Mechanical Sensor Technologies discusses the developments necessary to realize the growth of truly integrated sensors for use in physical, biological, optical, and chemical sensing, as well as future micro- and nanotechnologies.

Optical, Acoustic, Magnetic and Mechanical Sensor Technologies