Bubble Power

"Can superheroes Bubbleboy and Guppygirl save the day?"--Page 4 of cover.

Alkaline water electrolysis has a large industrial application and development potential in hydrogen energy owing to its high maturity and low cost. However, its moderate energy efficiency, especially caused by bubble effects, inhibits its use for large-scale hydrogen production. To overcome this shortcoming, this review first analyzes the bubble effect and summarizes the external operation methods, such as external field intensification, flow operation, fluctuation operation, and surfactant addition to the electrolyte, to enhance bubble separation in the electrolyzer. Then, electrode and flow channel structure optimization, particularly superhydrophilic and superaerophobic electrodes, and flow channels with varying heights, square column arrangements, and inlet/outlet numbers are highlighted. Finally, future research directions in alkaline water electrolysis technology are suggested to advance the industrial application of large-scale alkaline water electrolysis.

This monograph presents a systematic analysis of bubble system mathematics, using the mechanics of two-phase systems in non-equilibrium as the scope of analysis. The author introduces the thermodynamic foundations of bubble systems, ranging from the fundamental starting points to current research challenges. This book addresses a range of topics, including description methods of multi-phase systems, boundary and initial conditions as well as coupling requirements at the phase boundary. Moreover, it presents a detailed study of the basic problems of bubble dynamics in a liquid mass: growth (dynamically and thermally controlled), collapse, bubble pulsations, bubble rise and breakup. Special emphasis is placed on bubble dynamics in turbulent flows. The analysis results are used to write integral equations governing the rate of vapor generation (condensation) in non-equilibrium flows, thus creating a basis for solving a number of practical problems. This book is the first to present a comprehensive theory of boiling shock with applications to problems of critical discharge and flashing under the fast decompression conditions. Reynolds’ analogy was the key to solving a number of problems in subcooled forced-flow boiling, the theoretical results of which led to easy-to-use design formulas. This book is primarily aimed at graduate and post-graduate students specializing in hydrodynamics or heat and mass transfer, as well as research expert focused on two-phase flow. It will also serve as a comprehensive reference book for designers working in the field of power and aerospace technology.

Magnetic Domain Walls in Bubble Materials covers the physics of domain walls in bubble domain materials. The book describes the microscopic origins and characteristics of the material parameters; the principles of domain statics and the Landau-Lifshitz equation, which is the basic equation of magnetization dynamics; and its physical significance. The text then discusses the experimental techniques, both static and dynamic, used in studying domain walls; the static internal structure of bubble-domain walls; the Bloch-wall dynamics based on one-dimensional solutions of the Landau-Lifshitz equation; and the wall-motion theory. The theory to low velocity phenomena in domain walls containing vertical Bloch; high-velocity radial and quasi-planar wall motions; and nonlinear bubble translation including the implications of the theory for bubble motion in devices, are also considered. The book further surveys special phenomena involving vibrations and wave motions of walls, and the effects of microwave-frequency fields on walls. Engineers and materials researchers involved in the development of practical bubble devices will find the book invaluable.

The Acoustic Bubble describes the interaction of acoustic fields with bubbles in liquid. The book consists of five chapters. Chapter 1 provides a basic introduction to acoustics, including some of the more esoteric phenomena that can be seen when high-frequency high-intensity underwater sound is employed. Chapter 2 discusses the nucleation of cavitation and basic fluid dynamics, while Chapter 3 draws together the acoustics and bubble dynamics to discuss the free oscillation of a bubble and acoustic emissions from such activity. The acoustic probes that are often applied to study the behavior of a bubble when an externally-applied acoustic field drives it into oscillation is deliberated in Chapter 4. The last chapter outlines a variety of effects associated with acoustically-induced bubble activity. The bubble detection, sonoluminescence, sonochemistry, and pulse enhancement are also covered. This publication is a good reference for physics and engineering students and researchers intending to acquire knowledge of the acoustic interactions of acoustic fields with bubbles.

Magnetic bubbles are of interest to engineers because their properties can be used for important practical electronic devices and they are of interest to physicists because their properties are manifestations of intriguing physical principles. At the same time, the fabrication of useful configurations challenges the materials scientists and engineers. A technology of magnetic bubbles has developed to the point where commercial products are being marketed. In addition, new discovery and development are driving this technology toward substantially lower costs and presumably broader application. For all of these reasons there is a need to educate newcomers to this field in universities and in industry. The purpose of this book is to provide a text for a one-semester course that can be taught under headings of Solid State Physics, Materials Science, Computer Technology or Integrated Electronics. It is expected that the student of anyone of these disciplines will be interested in each of the chapters of this book to some degree, but may concentrate on some more than others, depending on the discipline. At the end of each chapter there is a brief summary which will serve as a reminder of the contents of the chapter but can also be read ahead of time to determine the depth of your interest in the chapter.