Low Temperature and Cryogenic Refrigeration


Book Description

Refrigeration plays a prominent role in our everyday lives, and cryogenics plays a major role in medical science, space technology and the cooling of low-temperature electronics. This volume contains chapters on basic refrigeration systems, non-compression refrigeration and cooling, and topics related to global environmental issues, alternative refrigerants, optimum refrigerant selection, cost-quality optimization of refrigerants, advanced thermodynamics of reverse-cycle machines, applications in medicine, cryogenics, heat pipes, gas-solid absorption refrigeration, multisalt resorption heat pumps, cryocoolers, thermoacoustic refrigeration, cryogenic heat transfer and enhancement and other topics covering theory, design, and applications, such as pulse tube refrigeration, which is the most efficient of all cryocoolers and can be used in space missions.




Cryogenic Mixed Refrigerant Processes


Book Description

Most conventional cryogenic refrigerators and liquefiers operate with pure fluids, the major exception being natural gas liquefiers that use mixed refrigerant processes. The fundamental aspects of mixed refrigerant processes, though very innovative, have not received the due attention in open literature in view of commercial interests. Hundreds of patents exist on different aspects of mixed refrigerant processes. However, it is difficult to piece together the existing information to choose an appropriate process and an optimum composition or a given application. The aim of the book is to teach (a.) the need for refrigerant mixtures, (b.) the type of mixtures that can be used for different refrigeration and liquefaction applications, (c.) the different processes that can be used and (d.) the methods to be adopted for choosing the components of a mixture and their concentration for different applications.




Cryogenic Helium Refrigeration for Middle and Large Powers


Book Description

This book offers a practical introduction to helium refrigeration engineering, taking a logical and structured approach to the design, building, commissioning, operation and maintenance of refrigeration systems. It begins with a short refresher of cryogenic principles, and a review of the theory of heat exchangers, allowing the reader to understand the importance of the heat exchanger role in the various thermodynamic cycle structures. The cycles are considered from the simplest (Joule Thomson) to the most complicated ones for the very large refrigeration plants and, finally, those operating at temperatures lower than 4.5 K. The focus then turns to the operation, ability and limitations of the main components, including room temperature cycle screw compressors, heat exchangers, cryogenic expansion turbines, cryogenic centrifugal compressors and circulators. The book also describes the basic principles of process control and studies the operating situations of helium plants, with emphasis on high level efficiency. A major issue is helium purity, and the book explains why helium is polluted, how to purify it and then how to check its purity, to ensure that all components are filled with pure helium prior to starting. Although the intention of the book is not to design thermodynamic cycles, it is of interest to a designer or operator of a cryogenic system to perform some simplified calculations to get an idea of how components or systems are behaving. Throughout the book, such calculations are generally performed using Microsoft® Excel and the Gaspak® or Hepak® software.




Applications of Cryogenic Technology


Book Description

Applications of Cryogenic Technology, Vol. 10, is the proceedings from the portion of the conference CRYO-90 sponsored by the Cryogenic Society of America (CSA). CRYO-90, held on the campus of the State University of New York, Binghamton, New York, was an unusual interdisciplinary event, drawing from the life sciences as well as the physical science and engineering areas of the low temperature community. Co-sponsoring CRYO-90 with CSA were the Society for Cryobiology and the Symposium on Invertebrate and Plant Cold Hardiness. These latter two organizations brought an exciting developing field to the conference, a field whose exploration will lead to the betterment of all mankind through improved cryosurgical and organ preservation techniques in addition to improved agricultural and herd yields under extreme conditions. Specific goals of the cryobiological community are cryopreservation, the arrest and recovery of living processes of cells, tissues and organs; and cryosurgery - the local cryodestruction of diseased cells while preserving the healthy surrounding tissue. These goals present great technological challenges. The technological requirements of the cryobiologist include the ability to cool tissues 6 at rates of 10 degrees per second (vitrification), to thaw frozen tissue without damaging the delicate cells, to freeze dry tissue using molecular distillation (vacuum) drying, to supercool cell structures below O°C without freezing, and to successfully store the preserved tissues and organs for any required length of time.




Cryogenic Technology and Applications


Book Description

Cryogenic Technology and Applications describes the need for smaller cryo-coolers as a result of the advances in the miniaturization of electrical and optical devices and the need for cooling and conducting efficiency. Cryogenic technology deals with materials at low temperatures and the physics of their behavior at these temps. The book demonstrates the ongoing new applications being discovered for cryo-cooled electrical and optical sensors and devices, with particular emphasis on high-end commercial applications in medical and scientific fields as well as in the aerospace and military industries. This book summarizes the important aspects of cryogenic technology critical to the design and development of refrigerators, cryo-coolers, and micro-coolers needed by various commercial, industrial, space and military systems. Cryogenic cooling plays an important role in unmanned aerial vehicle systems, infrared search and track sensors, missile warning receivers, satellite tracking systems, and a host of other commercial and military systems.* Provides an overview of the history of the development of cryogenic technology* Includes the latest information on micro-coolers for military and space applications* Offers detailed information on high-capacity cryogenic refrigerator systems used in applications such as food storage, high-power microwave and laser sensors, medical diagnostics, and infrared detectors




Low-capacity Cryogenic Refrigeration


Book Description

In the early 1980s, Graham Walker wrote his classic two-volume monograph Cryocoolers. Records show that sections of this work have been referenced more often and by more authors than any other cryogenic paper published in the mid-1980s. Nevertheless, the significant time lapse in so dynamica field and Walker and Bingham's experience of teaching short courses has revealed the need for a more up-to-date book - one that is more compact, lower in cost, and embraces more topics. Low-capacity Cryogenic Refrigeration provides an elementary yet comprehensive introduction to the subject, with diverse applications in scientific, medical, educational, military, and civil systems. It is complementary to the earlier two-volume work, but covers a wider field and has a wealth ofinformation about the new developments in the last fifteen years. In addition to descriptions of all the principal methods to achieve low-capacity cryogenic refrigeration, this new volume contains a valuable guide to the literature sources and references more advanced works.




Cryogenic Engineering and Technologies


Book Description

Cryogen-free cryogenics is leading a revolution in research and industry by its significant advantages over traditional liquid helium systems. This is the first overview for the field, covering the key technologies, conceptual design, fabrication, operation, performance, and applications of these systems. The contents cover important topics such as the operating principles of 4K cryocoolers, enabling technologies (including vibration reduction) for cryogen free systems, the cryogen- free superconducting magnet, and cryogen-free systems that reach mK. It highlights the wide range of applications in materials science, quantum physics, astronomy and space science, medical sciences and etc. Key features: Introduce technologies and practical know-how employed for cryogen-free systems of using 4 K cryocoolers to replace liquid helium; Address state of the arts of cryogen-free superconducting magnets, sub-kelvin refrigeration systems of He-3 sorption cooler, adiabatic demagnetization refrigerator (ADR) and dilution refrigerators (DR). Discuss applications of cryogen-free systems in modern instruments and equipment.




Optical Refrigeration


Book Description

Edited by the two top experts in the field with a panel of International contributors, this is a comprehensive up-to-date review of research and applications. Starting with the basic physical principles of laser cooling of solids, the monograph goes on to discuss the current theoretical issues being resolved and the increasing demands of growth and evaluation of high purity materials suitable for optical refrigeration, while also examining the design and applications of practical cryocoolers. An advanced text for scientists, researchers, engineers, and students (masters, PHDs and Postdoc) in laser and optical material science, and cryogenics.




Essentials and Applications of Food Engineering


Book Description

Essentials & Applications of Food Engineering provides a comprehensive understanding of food engineering operations and their practical and industrial utility. It presents pertinent case studies, solved numerical problems, and multiple choice questions in each chapter and serves as a ready reference for classroom teaching and exam preparations. The first part of this textbook contains the introductory topics on units and dimensions, material balance, energy balance, and fluid flow. The second part deals with the theory and applications of heat and mass transfer, psychrometry, and reaction kinetics. The subsequent chapters of the book present the heat and mass transfer operations such as evaporation, drying, refrigeration, freezing, mixing, and separation. The final section focuses on the thermal, non-thermal, and nanotechnology-based novel food processing techniques, 3D food printing, active and intelligent food packaging, and fundamentals of CFD modeling. Features Features 28 case studies to provide a substantial understanding of the practical and industrial applications of various food engineering operations Includes 178 solved numerical problems and 285 multiple choice questions Highlights the application of mass balance in food product traceability and the importance of viscosity measurement in a variety of food products Provides updated information on novel food processing techniques such as cold plasma, 3D food printing, nanospray drying, electrospraying, and electrospinning The textbook is designed for undergraduate and graduate students pursuing Food Technology and Food Process Engineering courses. This book would also be of interest to course instructors and food industry professionals.




Matter and Methods at Low Temperatures


Book Description

The aim of this book is to provide information about performing experi ments at low temperatures, as well as basic facts concerning the low tem perature properties of liquid and solid matter. To orient the reader, I begin with chapters on these low temperature properties. The major part of the book is then devoted to refrigeration techniques and to the physics on which they are based. Of equal importance, of course, are the definition and measurement of temperature; hence low temperature thermometry is extensively discussed in subsequent chapters. Finally, I describe a variety of design and construction techniques which have turned out to be useful over the years. The content of the book is based on the three-hour-per-week lecture course which I have given several times at the University of Bayreuth between 1983 and 1991. It should be particularly suited for advanced stu dents whose intended masters (diploma) or Ph.D. subject is experimental condensed matter physics at low temperatures. However, I believe that the book will also be of value to experienced scientists, since it describes sev eral very recent advances in experimental low temperature physics and technology, for example, new developments in nuclear refrigeration and thermometry.