Download or read book Theoretical and Experimental Investigation of Cylindrical Liquid filled Acoustic Lenses with D lambda Ratios Greater Than 15 written by Donald L. Folds and published by . This book was released on 1968 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing properties of liquid-filled cylindrical acoustic lenses are investigated theoretically and experimentally for d/lambda ratios greater than 15. A mathematical model which includes the effects of the lens shell is described and used to predict directivity patterns. Based on this model, a right-circular cylindrical lens, 40 cm in diameter, was constructed and tested at frequencies ranging from 25 to 900 khz. Agreement of experimental directivity patterns with those predicted demonstrated feasibility of the lens at d/lambda ratios up to 150, a factor of 10 greater than previously reported. Theoretical investigation indicates that for d/lambda ratios greater than 150 the elliptical cylindrical lens shows promise, but fabrication of an experimental model is yet to be undertaken. (Author).

Download or read book U S Government Research and Development Reports written by and published by . This book was released on 1968-04 with total page 1042 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Government Research Development Reports written by and published by . This book was released on 1968-05 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements written by and published by . This book was released on 1968 with total page 1250 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Government Research and Development Reports Index written by and published by . This book was released on 1968 with total page 1000 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of Scientific and Industrial Reports written by and published by . This book was released on 1968-05 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cumulative Index to Contemporary Acoustical Literature Listed in the Journal of the Acoustical Society of America Volumes 36 44 1964 1968 written by Acoustical Society of America and published by . This book was released on 1971 with total page 1116 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Index written by and published by . This book was released on 1968 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1968 with total page 1592 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government wide Index to Federal Research Development Reports written by and published by . This book was released on 1968 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An experimental study of acoustic lenses and prisms using cylindrical rods written by John David Gavenda and published by . This book was released on 1956 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Biconvex Liquid filled Acoustic Lens written by Jackie Lee Roudebush and published by . This book was released on 1969 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study has been made of the properties of a biconvex liquid-filled acoustic lens formed by pressurizing a refracting fluid between two deformable diaphragms. Trichlorotrifluoroethane was used as the refracting liquid and stainless steel sheets 76 cm in diameter and 0.3 mm (0.012 inch) thick were used as the diaphragm material. Distortion of the spherical surfaces due to the weight of the liquid was negligible because of the tension developed by the internal hydrostatic pressure (1.4 atmospheres for focal length 1.2 meters). Acoustic diffraction patterns measured at f/4.0 in water at frequencies from 200 KHz to 500 KHz compare favorably with patterns computed numerically. Multiple focal points were found and can be associated with multiple internal reflections. (Author).

Download or read book Propagation of Sound in Porous Media written by J.F. Allard and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has grown out of the research activities of the author in the fields of sound propagation in porous media and modelling of acoustic materials. It is assumed that the reader has a background of advanced calculus, including an introduction to differential equations, complex variables and matrix algebra. A prior exposure to theory of elasticity would be advantageous. Chapters 1-3 deal with sound propagation of plane waves in solids and fluids, and the topics of acoustic impedance and reflection coefficient are given a large emphasis. The topic of flow resistivity is presented in Chapter 2. Chapter 4 deals with sound propagation in porous materials having cylindrical pores. The topics of effective density, and of tortuosity, are presented. The thermal exchanges between the frame and the fluid, and the behaviour of the bulk modulus of the fluid, are described in this simple context. Chapter 5 is concerned with sound propagation in other porous materials, and the recent notions of characteristic dimensions, which describe thermal exchanges and the viscous forces at high frequencies, are introduced. In Chapter 6, the case of porous media having an elastic frame is considered in the context of Biot theory, where new topics described in Chapter 5 have been included.

Download or read book Fox and McDonald s Introduction to Fluid Mechanics written by Robert W. Fox and published by John Wiley & Sons. This book was released on 2020-06-30 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through ten editions, Fox and McDonald's Introduction to Fluid Mechanics has helped students understand the physical concepts, basic principles, and analysis methods of fluid mechanics. This market-leading textbook provides a balanced, systematic approach to mastering critical concepts with the proven Fox-McDonald solution methodology. In-depth yet accessible chapters present governing equations, clearly state assumptions, and relate mathematical results to corresponding physical behavior. Emphasis is placed on the use of control volumes to support a practical, theoretically-inclusive problem-solving approach to the subject. Each comprehensive chapter includes numerous, easy-to-follow examples that illustrate good solution technique and explain challenging points. A broad range of carefully selected topics describe how to apply the governing equations to various problems, and explain physical concepts to enable students to model real-world fluid flow situations. Topics include flow measurement, dimensional analysis and similitude, flow in pipes, ducts, and open channels, fluid machinery, and more. To enhance student learning, the book incorporates numerous pedagogical features including chapter summaries and learning objectives, end-of-chapter problems, useful equations, and design and open-ended problems that encourage students to apply fluid mechanics principles to the design of devices and systems.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Tweezers written by Philip H. Jones and published by Cambridge University Press. This book was released on 2015-12-03 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive guide to the theory, practice and applications of optical tweezers, combining state-of-the-art research with a strong pedagogic approach.

Download or read book Springer Handbook of Acoustics written by Thomas Rossing and published by Springer Science & Business Media. This book was released on 2007-06-21 with total page 1179 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an unparalleled modern handbook reflecting the richly interdisciplinary nature of acoustics edited by an acknowledged master in the field. The handbook reviews the most important areas of the subject, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest research and applications are incorporated throughout, including computer recognition and synthesis of speech, physiological acoustics, diagnostic imaging and therapeutic applications and acoustical oceanography. An accompanying CD-ROM contains audio and video files.