Download or read book Effects of Boundary layer Development on Cavitation Noise and Inception on a Hydrofoil written by and published by . This book was released on 1976 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Boundary Layer Development on Cavitation Noise and Inception on a Hydrofoil written by and published by . This book was released on 1976 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements are described of noise from cavitating flow over hydrofoils. The experiments were performed in a variable pressure water tunnel that was acoustically calibrated so that sound power levels could be deduced from the sound measurements. It was partially reverberant in the frequency range of interest. Cavitation was generated on the low-pressure side of a hydrofoil in the presence of a separated laminar boundary layer on the one hand and of a fully turbulent attached boundary layer on the other. The turbulent boundary layer was formed downstream of a trip, which was positioned near the leading edge. High-speed photographs show patterns of cavitation obtained in each case. Cavitation was also generated on the high-pressure side at negative angles of attack. The noise is shown to depend on the type of cavitation produced; for each type, dependence on speed and cavitation index has been determined. (Author).
Download or read book The Influence of Hydrofoil Oscillation on Boundary Layer Transition and Cavitation Noise written by Young T. Shen and published by . This book was released on 1981 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant effects of boundary layer characteristics on cavitation and the effect of unsteady cavitation on noise have been widely observed experimentally. In order to better understand these effects, an experiment with a two-dimensional hydrofoil, under sinusoidal pitching oscillation, was conducted in the 36-inch water tunnel. Three pin-hole-type pressure transducers were installed on the foil surface to measure pressure fluctuations and a hydrophone was used to measure the radiated cavitation noise. Two subjects are discussed in this paper: relationship of boundary layer transition and pressure fluctuations with the hydrofoil in oscillation, and noise generated by unsteady cavitation. The magnitudes of pressure fluctuations in transition and turbulent regions are found to be independent of oscillation amplitude and frequency. However, the development of boundary layer and occurrence of transition are delayed with an increase in oscillation frequency. The influence of hydrofoil oscillation on cavitation inception is also discussed. With the occurrence of leading edge sheet cavitation, a significant effect of foil oscillation on cavitation noise is measured. At high reduced frequencies, extensive cloud cavitation is formed during the final phase of sheet cavity collapse and the noise level is significantly increased. (Author).
Download or read book The Influence of Hydrofoil Oscillation on Boundary Layer Transition and Cavitation Noise written by Young T. Shen and published by . This book was released on 1981 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant effects of boundary layer characteristics on cavitation and the effect of unsteady cavitation on noise have been widely observed experimentally. In order to better understand these effects, an experiment with a two-dimensional hydrofoil, under sinusoidal pitching oscillation, was conducted in the 36-inch water tunnel. Three pin-hole-type pressure transducers were installed on the foil surface to measure pressure fluctuations and a hydrophone was used to measure the radiated cavitation noise. Two subjects are discussed in this paper: relationship of boundary layer transition and pressure fluctuations with the hydrofoil in oscillation, and noise generated by unsteady cavitation. The magnitudes of pressure fluctuations in transition and turbulent regions are found to be independent of oscillation amplitude and frequency. However, the development of boundary layer and occurrence of transition are delayed with an increase in oscillation frequency. The influence of hydrofoil oscillation on cavitation inception is also discussed. With the occurrence of leading edge sheet cavitation, a significant effect of foil oscillation on cavitation noise is measured. At high reduced frequencies, extensive cloud cavitation is formed during the final phase of sheet cavity collapse and the noise level is significantly increased. (Author).
Download or read book The Effects of Surface Roughness on Cavitation Inception Speeds of a Hydrofoil written by William G. Souders and published by . This book was released on 1968 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Methods recently derived for the prediction of cavitation inception velocities over isolated roughnesses on arbitrary hydrodynamic bodies were applied to an NACA 16 series hydrofoil section. The required foil pressure distribution and boundary layer growth are calculated theoretically. The results present the minimum or critical height of several types of roughness elements which would produce cavitation inception as a function of foil station, speed, angle of attack, and submergence depth. The results show the deteriorating effect of various roughness geometries on the cavitation inception speed and indicate the necessity for rigid tolerances in the design, fabrication, and maintenance of hydrofoil surfaces. (Author).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1981 with total page 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 Government Reports Announcements Index written by and published by . This book was released on 1977 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cavitation Inception Observations on Two Axisymmetric Headforms written by Thomas T. Huang and published by . This book was released on 1977 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cavitation inception observations on two axisymmetric headforms were made in the DTNSRDC 36-inch water tunnel. The results indicate that cavitation inception on a headform with natural flow transition is significantly affected by the air content of the water. The effect of air content on cavitation inception on a headform with laminar separation is less pronounced. Visible cavitation inception never occurred at the locations of minimum static pressure but was observed to occur in the region of natural transition and the separated shear layer following laminar separation. It is concluded that both the viscous effects and cavitatable microbubble population are extremely important parameters governing the cavitation inception process. (Author).
Download or read book Hydrodynamics of Pumps written by Christopher E. Brennen and published by Cambridge University Press. This book was released on 2011-03-28 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrodynamics of Pumps is a reference for pump experts and a textbook for advanced students. It examines the fluid dynamics of liquid turbomachines, particularly pumps, focusing on special problems and design issues associated with the flow of liquid through a rotating machine. There are two characteristics of a liquid that lead to problems and cause a significantly different set of concerns than those in gas turbines. These are the potential for cavitation and the high density of liquids, which enhances the possibility of damaging, unsteady flows and forces. The book begins with an introduction to the subject, including cavitation, unsteady flows and turbomachinery, basic pump design and performance principles. Chapter topics include flow features, cavitation parameters and inception, bubble dynamics, cavitation effects on pump performance, and unsteady flows and vibration in pumps - discussed in the three final chapters. The book is richly illustrated and includes many practical examples.
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 Cavitation written by Yves Lecoffre and published by CRC Press. This book was released on 1999-01-01 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text deals with the concept that cavitation is the main limitation to the performance of hydraulic components. Topics covered include the vaporization of liquids due to high velocities or pressure fluctuations, and the effects of cavitation on the performances of rotary machinery. One chapter is devoted to cavitation noise which concerns many users, including surface ships and submarines, and the author finishes with some examples of the use of cavitation and subject-specific measuring techniques.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanics of Flow Induced Sound and Vibration V2 written by William K. Blake and published by Elsevier. This book was released on 2012-12-02 with total page 569 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Flow-Induced Sound and Vibration V2
Download or read book Mechanics of Flow Induced Sound and Vibration Volume 1 written by William K. Blake and published by Academic Press. This book was released on 2017-06-13 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Flow-Induced Sound and Vibration, Volume 1: General Concepts and Elementary Sources, Second Edition, enables readers to fully understand flow-induced vibration and sound, unifying the disciplines of fluid dynamics, structural dynamics, vibration, acoustics, and statistics in order to classify and examine each of the leading sources of vibration and sound induced by various types of fluid motion. Starting with classical theories of aeroacoustics and hydroacoustics, a formalism of integral solutions valid for sources near boundaries is developed and then broadened to address different source types, including jet noise, flow tones, dipole sound from cylinders, and cavitation noise. Step-by-step derivations clearly identify any assumptions made throughout. Each chapter is illustrated with comparisons of leading formulas and measured data. Along with its companion, Mechanics of Flow-Induced Sound and Vibration, Volume 2: Complex Flow-Structure Interactions, the book covers everything an engineer needs to understand flow-induced sound and vibration. This book will be essential reading for postgraduate students, and for engineers and researchers with an interest in aerospace, ships and submarines, offshore structures, construction, and ventilation. Presents every important topic in flow-induced sound and vibration Covers all aspects of the topics addressed, from fundamental theory, to the analytical formulas used in practice Provides the building blocks of computer modeling for flow-induced sound and vibration
Download or read book Fourteenth Symposium Naval Hydrodynamics written by United States. Office of Naval Research and published by . This book was released on 1982 with total page 672 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings written by and published by . This book was released on 1992 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Hydroscience written by Ven Te Chow and published by Elsevier. This book was released on 2013-10-22 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Hydroscience, Volume 12-1981 covers articles in the areas of fluid mechanics and hydrology. The book presents articles on advances in cavitation research, applied stochastic theory of storage in evolution, and echohydrodynamics. The text also includes articles on the usefulness and the basic nature of the application of pattern recognition in the context of hydrologic data analysis. A summary of the Hydrologic Engineering Center's experience in water resources system simulation is also encompassed. The book will prove invaluable to hydrologists, practitioners handling the design and control of hydraulic structures and machinery, and engineers working in the water industry.
