Ultrasonic Sensors for Chemical and Process Plant

Abstract

This admirably readable book provides a clear account of a variety of sensors that are based on ultrasound and used in the process and chemical industries. It is unfortunate that the publishers have truncated the cover title to the rather misleading Ultrasonic Sensors. The author is, in fact, at pains to point out that this is not a book on ultrasonic sensing techniques in general, but only techniques applied in `industrial plant in which fluids are processed, used or stored'. The book is aimed at practising scientists and engineers who are not specialists in ultrasonics, and a particular strength is the first section, which covers the physics of ultrasound and ultrasonic transducers. In seven chapters, the author provides a comprehensive and interesting introduction to the field that is jargon-free and uses only the minimum mathematics. The chapter on piezoelectric transducers in particular is probably the best general introduction to the subject I've come across. The treatment does not lack rigour - the appropriate use of references and the comprehensive bibliography are amongst the book's strong points - but the author succeeds in using anecdote and humour to good effect, particularly in this first section. Part 2 of the book Description of ultrasonic sensors is the heart of the work, but surprisingly, the weakest section. The clarity of style is still evident, the diagrams are well chosen and helpful, and individual sensing techniques are well described. However, the reader is left with a sense that the thematic structure has been lost. Liquid level detection, for instance, is split between chapter 8 Point level detectors (and some continuous level detectors) and chapter 11 Sonar. In between these is a rag-bag chapter 9 ( Sensors where the velocity of ultrasound is determined) and a very good chapter on flow measurement. The titles of chapters 8 and 9 alone demonstrate the author's struggle to impose some logical order on what is a diverse collection of techniques linked only by the use of ultrasound at some point in the measurement process. The final section consists of six extended appendices, which are logical and well structured. The appendices dealing with acoustic velocity, acoustic attenuation, waveguides, and piezoelectric materials are authoritative and fascinating. Here the author appears to be dealing in more detail with some of his own pet interests; the result is a mine of useful information, concisely presented. A directory of suppliers and bibliography round off the book. The author's enthusiasm for his subject is apparent throughout this book, as is his ability to explain technically difficult issues in an enlightening and non-mathematical way. It deserves a wide readership.