Download or read book Cavitation Nucleation by Energetic Particles written by C. West and published by . This book was released on 1967 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cavitation Bubble Nucleation by Energetic Particles written by and published by . This book was released on 1998 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early sixties, experimental measurements using a bubble chamber confirmed quantitatively the thermal spike theory of bubble nucleation by energetic particles: the energy of the slow, heavy alpha decay recoils used in those experiments matched the calculated bubble nucleation energy to within a few percent. It was a triumph, but was soon to be followed by a puzzle. Within a couple of years, experiments on similar liquids, but well below their normal boiling points, placed under tensile stress showed that the calculated bubble nucleation energy was an order of magnitude less than the recoil energy. Why should the theory work so well in the one case and so badly in the other? How did the liquid, or the recoil particle, "know" the difference between the two experiments? Another mathematical model of the same physical process, introduced in 1967, showed qualitatively why different analyses would be needed for liquids with high and low vapor pressures under positive or negative pressures. But, the quantitative agreement between the calculated nucleation energy and the recoil energy was still poor--the former being smaller by a factor of two to three. In this report, the 1967 analysis is extended and refined: the qualitative understanding of the difference between positive and negative pressure nucleation, "boiling" and "cavitation" respectively, is retained, and agreement between the negative pressure calculated to be needed for nucleation and the energy calculated to be available is much improved. A plot of the calculated negative pressure needed to induce bubble formation against the measured value now has a slope of 1.0, although there is still considerable scatter in the individual points.
Download or read book Cavitation nucleation by enegetic particles written by C. West and published by . This book was released on 1967 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cavitation in a Mercury Target written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent theoretical work on the formation of bubble nucleation centers by energetic particles leads to some reasonably credible calculations of the maximum negative pressure that might be sustained without bubble formation in the mercury target of the Spallation Neutron Source.
Download or read book Solidification Processing of Metallic Alloys Under External Fields written by Dmitry G. Eskin and published by Springer. This book was released on 2018-10-09 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the application of external physical fields to the solidification processing of metallic alloys. Leading academics from around the world present comprehensive and critical reviews on state-of-the-art research and discuss possible future directions. Major physical fields, including electromagnetic, electric, acoustic, and thermal, are considered. In addition, the most advanced synchrotron X-ray based real-time and in-situ studies and numerical modeling methodologies are reviewed and discussed, with a special emphasis on their applications to the solidification processes. Throughout, all chapters are illustrated with both historical and very recent research cases, including typical examples of in-situ studies, modeling, and simulation. This book contains essential knowledge and information suitable for a wide audience, from undergraduate and postgraduate students to academics, practicing researchers, and engineers in materials, metallurgy, and manufacturing.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 1460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Cavitation written by Sivakumar Manickam and published by CRC Press. This book was released on 2014-08-05 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: As nanomaterials and their end products occupy the pinnacle position of consumer markets, it becomes vital to analyze their generation processes. One of the green chemistry principles underlines the need for unusual energy sources to generate them. Utilizing the extreme energy from the collapse of cavitation bubbles, generated by either ultrasound or hydrodynamic forces, for the generation of nanomaterials is a merit to consider in this "Green Chemical Processing Era." A wide range of nanomaterials have been developed in the past decade using cavitation or coupling cavitation with other techniques such as microwave, photochemistry, and electrochemistry, resulting in nanomaterials with unique morphologies, reduced size, narrow size distribution, and innumerous advantages. While a few currently available books deal with the fundamental aspects of cavitation and sonochemistry, this book is devoted specifically to the technologically important nanomaterials obtained by cavitation.
Download or read book Nucleation of Cavitation by Alpha Particle Irradiation of Liquid Helium written by John Russell Shadley and published by . This book was released on 1970 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cavitation in Biomedicine written by Mingxi Wan and published by Springer. This book was released on 2015-08-29 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers a systematic introduction to the engineering principles and techniques of cavitation in biomedicine on the basis of its physics and mechanism. Adopting an interdisciplinary approach, it covers areas of interest ranging from physics and engineering to the biological and medical sciences. Individual chapters introduce the fundamentals of cavitation, describe its characterization, control and imaging techniques, and present cavitation-enhanced thermal and mechanical effects and their applications. Intended as both a reference work for graduate students, and as a guide for scientists and engineers who work with cavitation in biomedicine, it provides a broad and solid foundation of knowledge. The aim is to bridge the different disciplines involved, and to promote cross-discipline research, thus encouraging innovations in the scientific research and engineering applications alike. Dr. Mingxi Wan is a professor at Department of Biomedical Engineering, Xi’an Jiao Tong University, Xi’an, Shaanxi, China; Dr. Yi Feng works at Department of Biomedical Engineering, Xi’an Jiao Tong University, Xi’an, Shaanxi, China; Dr. Gail ter Haar is a professor at The Institute of Cancer Research, Sutton, Surry, UK.
Download or read book Cavitation and Bubble Dynamics written by Christopher E. Brennen and published by Cambridge University Press. This book was released on 2014 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cavitation and Bubble Dynamics deals with fundamental physical processes of bubble dynamics and cavitation for graduate students and researchers.
Download or read book Energy Aspects of Acoustic Cavitation and Sonochemistry written by Oualid Hamdaoui and published by Elsevier. This book was released on 2022-08-06 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy Aspects of Acoustic Cavitation and Sonochemistry: Fundamentals and Engineering covers topics ranging from fundamental modeling to up-scaled experiments. The book relates acoustic cavitation and its intrinsic energy balance to macroscopic physical and chemical events that are analyzed from an energetic perspective. Outcomes are directly projected into practical applications and technological assessments covering energy consumption, thermal dissipation, and energy efficiency of a diverse set of applications in mixed phase synthesis, environmental remediation and materials chemistry. Special interest is dedicated to the sonochemical production of hydrogen and its energetic dimensions. Due to the sensitive energy balance that governs this process, this is seen as a "green process" for the production of future energy carriers. - Provides a concise and detailed description of energy conversion and exchange within the single acoustic cavitation bubble and bubble population, accompanying physical and chemical effects - Features a comprehensive approach that is supported by experiments and the modeling of energy concentration within the sonochemical reactor, jointly with energy dissipation and damping phenomenon - Gives a clear definition of energy efficiency metrics of industrial sono-processes and their application to the main emergent industrial fields harnessing acoustic cavitation and sonochemistry, notably for the production of hydrogen
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976-02 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cavitation Reaction Engineering written by Y.T. Shah and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: The literature on cavitation chemistry is ripe with conjectures, possibilities, heuris tic arguments, and intelligent guesses. The chemical effects of cavitation have been explained by means of many theories, consisting of empirical constants, adjustable parameters, and the like. The chemists working with cavitation chemistry agree that the phenomenon is very complex and system specific. Mathematicians and physi cists have offered partial solutions to the observed phenomena on the basis of cavitation parameters, whereas chemists have attempted explanations based on the modes of reaction and the detection of intermediate chemical species. Nevertheless, no one has been able to formulate a unified theme, however crude, for its effects on the basis of the known parameters, such as cavitation and transient chemistry involving extremely high temperatures of nanosecond durations. When one surveys the literature on cavitation-assisted reactions, it is clear that the approach so far has been "Edisonian" in nature. While a large number of reactions have showed either enhanced yields or reduced reaction times, many reactions have remained unaffected in the presence of cavitation. The success or failure of cavitation reactions ultimately depends on the collapse of the cavity. Cavitation chemistry is based on the principles of the formation of small transient cavities, their growth and implosion, which produce chemical reactions caused by the generation of extreme pressures and temperatures and a high degree of micro turbulence.
Download or read book Advances in Heat Transfer written by George A. Greene and published by Elsevier. This book was released on 2006-10-17 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Heat Transfer fills the information gap between regularly scheduled journals and university level textbooks by providing in-depth review articles over a broader scope than in journals or texts. The articles, which serve as a broad review for experts in the field, will also be of great interest to non-specialists who need to keep up-to- date with the results of the latest research. It is essential reading for all mechanical, chemical and industrial engineers working in the field of heat transfer, graduate schools or industry. - Provides an overview of review articles on topics of current interest - Bridges the gap between academic researchers and practitioners in industry - A long-running and prestigious series
Download or read book Bubble Mediated Focused Ultrasound written by Tianming Wu and published by . This book was released on 2007 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Cavitation is often the result of rapid and intense hyperthermia using high-intensity focused ultrasound (HIFU) to treat malignant tumors deep in tissue. With proper parameters, cavitation bubbles are very efficient in transforming acoustic energy into heat. In vivo and in vitro studies have shown that bubble enhanced heating can potentially increase HIFU efficacy. However, sporadic nucleation of bubbles and subsequent nonlinear oscillations allow uncontrolled cavitation to induce irregular lesions and other unpredictable and thus undesirable effects. This work takes a modeling approach to investigate the physical mechanisms necessary for developing bubble-mediated HIFU therapy with a satisfactory degree of predictability and controllability. Controlled nucleation is possible with a transient vapor cavity generated from a laser heated gold nano-particle in combination with proper acoustic conditions. Preliminary experimental studies in optically transparent gel phantoms have been conducted and results show that the combined use of laser, HIFU and nano-particles reduces the cavitation threshold significantly, and the temporal and spatial characteristics of cavitation events can be controlled by the sound-light interaction mediated with the particles. A mathematical model for particle heating, vapor bubble nucleation and the subsequent bubble dynamics is constructed to predict cavitation thresholds of laser and HIFU energy, and results are comparable with experiments. A parametric study is presented to investigate the effects of particle size and laser pulse length for the optimization of this technique to generate cavitation on demand. In another effort, the interactions of acoustic propagation and the thermal effects in the presence of cavitation bubbles (mostly gas) and boiling bubbles (mostly vapor) are modeled. By introducing temperature dependent viscosity, surface tension coefficient and vapor pressure into the nonlinear gas bubble dynamics, the variation of the bubble radial oscillations, size distributions and subsidiary heating due to the temperature elevation are studied. A continuum bubbly medium is constructed with effective sound speed and attenuation derived from the temperature dependent nonlinear gas bubble When boiling occurs, the vapor bubbles are simply modeled as pressure release cavities. An iterative simulation for acoustic, cavitation(boiling) and thermal fields is then constructed to model the lesion developments, with updating time scales estimated from intrinsic space-time scales related to the evolution of bubble clusters observed from experiments. Results indicate that cavitation enhances ultrasonic absorption and creates larger and wider lesions in a shorter time. The scattering due to the impedance mismatch in the cavitation zone is responsible for the irregular lesions. The heating from cavitation bubbles also accelerates the emerging of vapor bubbles and boiling. The current scheme has exhibited its effectiveness in predicting the position, shape and size of an evolving lesion during bubble-mediated HIFU therapy, given the thermal and acoustical properties of the target tissue and the ultrasonic insonation parameters such as focal intensity and exposure duration.
Download or read book Mechanism of Ultrasonic Cavitation Nucleation by Quantized Vortices written by and published by . This book was released on 1975 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Air Content on Cavitation Nucleation written by Gary Lohman and published by . This book was released on 1974 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
