Cryocoolers

Cryocoolers

Journal of Mechanical Working Technology, 15 (1987) 241-244 Elsevier SciencePublishersB.V., AmsterdRm-- Printed in The Netherlands 241 Book Reviews ...

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Journal of Mechanical Working Technology, 15 (1987) 241-244 Elsevier SciencePublishersB.V., AmsterdRm-- Printed in The Netherlands

241

Book Reviews Cryocoolers, edited by Graham Walker, Plenum, New York, 1983. Two volumes: ISBN 0-306-40715-9 (v. 1 ), xxvi + 365 pages, illustrated, hard-cover $49.50; ISBN 0-306-41219-5 (v. 2), xxvi + 405 pages, illustrated, hard-cover

$55.00. It is natural for technology to spawn new words to fill the dictionaries, but this is not yet an every-day event. Nor is it so usual to find a new generic term, coined to describe a class of devices which individually have been around for a good many (recent) years. Professor Walker has defined "cryocoolers" as "cryogenic cooling engines" - - devices to produce refrigeration below 120 K. Indeed two substantial volumes do not prove sufficient for the task. Only in Chapter I does the full range of cryocoolers receive attention, being variously summarised and classified and ultimately divided into rotary and reciprocating types, corresponding respectively to large liquefaction plant and to small cooling systems whose principal applications lie in spacecraft and airborne infrared sensors. It is to such small and intermediate capacity reciprocating coolers that these two volumes are devoted. An historical survey of the field concentrates on recent developments, in deference to the earlier definitive work by S.C. Collins who has contributed a Foreword. Basic thermodynamics is introduced in Chapter 2, leading to a theoretical treatment of the regenerative Stirling cycle and the general algebra of the Rallis regenerative cycle. From this is developed a parametric analysis of several less-than-perfect variants of the basic Stirling or Ericsson Cycle. The operating principles of other regenerative types, namely the Vuilleumier, Solvay and G i f f o r d ~ M c M a h o n cycles are all illustrated. Next to be introduced are cryocoolers with recuperative heat exchangers, and the principles of Joule---Brayton, Joule---Thomson, Claude, Siemens and Linde--Hampson cycles are reviewed in turn. Chapter 2 finishes with a steadyflow analysis of recuperative cycles and a treatment of non-ideal compressors and expanders. Subsequent chapters are individually devoted to one of the cycles already mentioned. The usual pattern is an historical sketch followed by a review of the major variants with appropriate theoretical details, backed up by exhaustive reference to practical realisations of each type as commercial products. The discussion of design constraints imposed by the various cycles is one of the most, fascinating features of these books, turning what should be a work of extraordinarily narrow appeal into a mine of design insights for the general reader. This wider audience will much appreciate the prose style which is lucid and readily assimilated while verging on the encyclopaedic in its coverage. The

242 newcomer to the field will find this the definitive introductory work, while the established specialists are going to need a copy just to check that their name is there, and spelled correctly. All this material constitutes Volume 1, entitled "Fundamentals", while Volume 2 assembles various "Applications": Applications of the Fundamentals, that is, not of Cryocoolers. In fact, the first two chapters of Volume 2 provide extensive treatments of"Heat Exchangers in Cryocoolers" and "Some Aspects of Design". As before the coverage is comprehensive and far from superficial. Sources are not treated simply as a catalogue of who has done what, but major results are presented in detail with techniques and devices freely illustrated. Design topics covered include balancing, bearings, seals, materials, cooling and electric drives, all discussed in the context of low temperature operation of compact systems. The remaining chapters are all contributed by other authors. The design theme is pursued by the late Fred Chellis of Cryogenic Technology Inc. under the heading of "Practical Problems in Cryocooler Design and Operation". Ray Radebaugh of the National Bureau of Standards deals with the thermodynamic fundamentals of cryo-cooling, discussing first a variety of exotic refrigeration techniques and then devoting a complete specialised chapter to "VeryLow-Temperature Cooling Systems", here defined to cover temperatures below 1 K. Finally, Russian and Japanese developments are thoroughly reviewed by Professor Evgeny Mikulin from the Baumann Institute in Moscow and by Yoshihiro Ishizaki of the University of Tokyo. Despite this varied authorship, editorial control has not been lost. The coherent appearance of the books is helped especially by the consistent style of line illustrations, which are an excellent and generous feature of both volumes. Supplemented by just a few black and white photographs, these little drawings add considerably to the ease with which this enormous range of topics can be assimilated. Each chapter is supported by a list of references, but a complete Bibliography, running to some fifty pages, appears in Volume 2. Likely to prove a boon to other workers, this is also indicative of the effort which Professor Walker has put into his tour-de-force. The list is supported by an Appendix giving guidance on cryogenic literature sources, while two other Appendices provide a glossary of terms and a list of interested organisations and manufacturers. Readers who appreciated Professor Walker's previous book on "Stifling Engines" will need no urging to sample his latest work. It is no mean achievement to have produced two definitive text books, albeit on related topics. To have succeeded, too, in making an arcane field accessible to the general engineer without compromising the depth of specialist treatment is to set a light for others to folIow. And to show, amongst all this lavishly funded paraphernalia, a suggestion for a "rubber-band refrigerator" (Volume 2, p. 154, in the

243 chapter by Radebaugh) is to demonstrate that humour and intellectual enjoyment can be kept alive alongside the most intensive study. D.S. THOMPSON

Metal Cutting, second edition, by E.M. Trent, Butterworths, London, 1984. ISBN 0-408-10856-8, x + 245 pages, illustrated, hard-cover, £19.50. The accuracy levels required of machined components, the developments in the field of numerically controlled machine tools and advanced manufacturing systems, and the advent of new metals and alloys, are a few of the reasons for the increasing significance and relevance of studies in the field of metal cutting. This book has been written with strong emphasis on the metallurgical aspects of cutting technology. Chapters six, seven and eight on the subject of cuttingtool materials, span over ninety pages covering all the major tool categories, tool wear and tool life, conditions of use and further developments. The book treats the basic aspects of metal-cutting science and covers the operations and terminology, chip-formation principles, forces in cutting, heat in metal cutting, cutting-tool materials, machinability and coolants and lubricants. The extensive coverage given to cutting-tool materials makes the book a valuable reference source for practising engineers. The book is illustrated with an excellent collection of photomicrographs and scanning electron micrographs showing the structure of cutting-tool materials, tool failure and wear surfaces. Chapter nine, which deals with machinability, is particularly useful as it covers most of the engineering materials and alloys. The book is a good source of grouped detailed information about the current state of development in cutting-tool technology. It is recommended reading for engineers and researchers in the field of production technology. N.N.Z. GINDY

Metal Cutting Principles, by M.C. Shaw, Oxford University Press, 1984. ISBN 0-19-859002-4, xxii + 594 pages, illustrated, hard cover, £60. Metal cutting is considered one of the most important methods of shaping components. The developments in the field of numerically controlled machine tool and advanced manufacturing systems is another reason for the increasing relevancy and significance of studies in the field of metal removal technology. This book written by Professor Milton C. Shaw is an updated version of his