This book describes and explains the fundamental physical processes involved in bubble dynamics and the phenomenon of cavitation. It is intended as a combination of a reference book for those scientists and engineers who work with cavitation or bubble dynamics and as a monograph for advanced students interested in some of the basic problems associated with this category of multiphase flows. A basic knowledge of fluid flow and heat transfer is assumed but otherwise the analytical methods presented are developed from basic principles.

The book begins with a chapter on nucleation and describes both the theory and observations of nucleation in flowing and non-flowing systems. The following three chapters provide a systematic treatment of the dynamics of the growth, collapse or oscillation of individual bubbles in otherwise quiescent liquids. Chapter 4 summarizes the state of knowledge of the motion of bubbles in liquids. Chapter 5 describes some of the phenomena which occur in homogeneous bubbly flows with particular emphasis on cloud cavitation and this is followed by a chapter summarizing some of the experiemntal observations of cavitating flows. The last chapter provides a review of the free streamline methods used to treat separated cavity flows with large attached cavities.

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Cavitation and Bubble Dynamics

A critical review of the intrinsic nature of vortex-induced vibrations

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Forces on cylinders and plates in an oscillating fluid

Any device aiming to harness the abundant clean and renewable energy from ocean and other water resources must have high energy density, be unobtrusive, have low maintenance, be robust, meet life cycle cost targets, and have a 10-20 year life. The vortex induced vibration aquatic clean energy (VIVACE) converter-invented by Bernitsas and Raghavan, patent pending through the University of Michigan-satisfies those criteria. It converts ocean/river current hydrokinetic energy to a usable form of energy such as electricity using VIV successfully and efficiently for the first time. VIVACE is based on the idea of maximizing rather than spoiling vortex shedding and exploiting rather than suppressing VIV. It introduces optimal damping for energy conversion while maintaining VIV over a broad range of vortex shedding synchronization. VIV occurs over very broad ranges of Reynolds (Re) number Only three transition regions suppress VIV. Thus, even from currents as slow as 0.25 m/s, VIVACE can extract energy with high power conversion ratio making ocean/river current energy a more accessible and economically viable resource. In this paper, the underlying concepts of the VIVACE converter are discussed. The designs of the physical model and laboratory prototype are presented. A mathematical model is developed, and design particulars for a wide range of application scales are calculated. Experimental measurements on the laboratory prototype are reported in the sequel paper and used here for preliminary benchmarking.

VIVACE (Vortex Induced Vibration Aquatic Clean Energy): A New Concept in Generation of Clean and Renewable Energy From Fluid Flow

General Principles and Practices. Types of Pile. Piling Equipment and Methods. Calculating the Resistance of Piles to Compressive Loads. Pile Groups under Compressive Loading. The Design of Piled Foundations to Resist Uplift and Lateral Loading. The Structural Design of Piles and Pile Groups. Piling for Marine Structures. Miscellaneous Piling Problems. The Durability of Piled Foundations. Site Investigations, Piling Contracts, Pile Testing. Appendix - Properties of Materials

J.W. Johnson

Papers

The Force Exerted by Surface Waves on Piles