Download or read book Investigation of Performance Degradation of Evaporator for Low Temperature Refrigeration Applications written by Jan Muehlbauer and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat and Mass Transfer in the Melting of Frost written by William F. Mohs and published by Springer. This book was released on 2015-07-01 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Brief is aimed at engineers and researchers involved in the refrigeration industry: specifically, those interested in energy utilization and system efficiency. The book presents what the authors believe is the first comprehensive frost melting study involving all aspects of heat and mass transfer. The volume’s description of in-plane and normal digital images of frost growth and melting is also unique in the field, and the digital analysis technique offers an advantage over invasive measurement methods. The scope of book’s coverage includes modeling and experimentation for the frost formation and melting processes. The key sub-specialties to which the book are aimed include refrigeration system analysis and design, coupled heat and mass transfer, and phase-change processes.

Download or read book Refrigeration Systems and Applications written by Ibrahim Dinçer and published by John Wiley & Sons. This book was released on 2011-08-10 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Refrigeration Systems and Applications, 2nd edition offers a comprehensive treatise that addresses real-life technical and operational problems, enabling the reader to gain an understanding of the fundamental principles and the practical applications of refrigeration technology. New and unique analysis techniques (including exergy as a potential tool), models, correlations, procedures and applications are covered, and recent developments in the field are included - many of which are taken from the author's own research activities in this area. The book also includes some discussion of global warming issues and its potential solutions. Enables the reader to gain an understanding of the fundamental principles and the practical applications of refrigeration technologies. Discusses crucial industrial technical and operational problems, as well as new performance improvement techniques and tools for better design and analysis. Includes fundamental aspects of thermodynamics, fluid flow, and heat transfer; refrigerants; refrigeration cycles and systems; advanced refrigeration cycles and systems, including some novel applications; heat pumps; heat pipes; and many more. Provides easy to follow explanations, numerous new chapter-end problems and worked-out examples as learning aids for students and instructors. Refrigeration is extensively used in a variety of thermal engineering applications ranging from the cooling of electronic devices to food cooling processes. Its wide-ranging implications and applications mean that this industry plays a key role in national and international economies, and it continues to be an area of active research and development. Refrigeration Systems and Applications, 2nd edition forms a useful reference source for graduate and postgraduate students and researchers in academia and as well as practicing engineers working in this important field who are interested in refrigeration systems and applications and the methods and analysis tools for their analysis, design and performance improvement.

Download or read book Handbook of Research on Advances and Applications in Refrigeration Systems and Technologies written by Gaspar, Pedro Dinis and published by IGI Global. This book was released on 2015-08-28 with total page 1037 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, the sustainability and safety of perishable foods has become a major consumer concern, and refrigeration systems play an important role in the processing, distribution, and storage of such foods. To improve the efficiency of food preservation technologies, it is necessary to explore new technological and scientific advances both in materials and processes. The Handbook of Research on Advances and Applications in Refrigeration Systems and Technologies gathers state-of-the-art research related to thermal performance and energy-efficiency. Covering a diverse array of subjects—from the challenges of surface-area frost-formation on evaporators to the carbon footprint of refrigerant chemicals—this publication provides a broad insight into the optimization of cold-supply chains and serves as an essential reference text for undergraduate students, practicing engineers, researchers, educators, and policymakers.

Download or read book Evaporator Performance Investigation for Residential Air conditioning Application Using Mixed Refrigerants written by Maciej Chwalowski and published by . This book was released on 1991 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design of the heat exchanger utilizing nonazeotropic refrigerant in an air conditioning application presents unique problems due to the phase change of the moist air and the variable specific heat of the evaporating refrigerant mixture. This study discusses the performance analysis and the design procedure of a cross counterflow heat exchanger working as an evaporator in an experimental system which simulated a residential air conditioning application. The design of the heat exchanger, used for the experimental testing, consisted of several depth rows. Separated banks permitted the determination of the sensible and the latent heat loads for each bank and the heat profiles across the heat exchanger. The interaction between the refrigerant mixture and the moist air was quantified by determining the temperature profiles of both media and the moisture removal rate. The overall heat transfer coefficient for each bank of the heat exchanger was determined from the measured quantities. The effect of the change of the mixture composition on heat exchanger performance was evaluated. The focus of the theoretical study was the development of the effectiveness/NTU (epsilon/NTU) relationships with the use of the experimentally derived quantities for moist air flowing across the heat exchanger. For moist air, the variable mixture specific heat, air and heat profiles obtained from the experimental results were utilized to obtain the expression for epsilon/NTU. The derived epsilon/NTU relations were verified and found to be in good agreement with dry and moist air test results. This study resulted an understanding of an application of a refrigerant mixture working fluid in an evaporator and provided tools to design such a heat exchanger.

Download or read book IMDC SDSP 2020 written by Raed Abd-Alhameed and published by European Alliance for Innovation. This book was released on 2020-09-09 with total page 1619 pages. Available in PDF, EPUB and Kindle. Book excerpt: IMDC-SDSP conference offers an exceptional platform and opportunity for practitioners, industry experts, technocrats, academics, information scientists, innovators, postgraduate students, and research scholars to share their experiences for the advancement of knowledge and obtain critical feedback on their work. The timing of this conference coincides with the rise of Big Data, Artificial Intelligence powered applications, Cognitive Communications, Green Energy, Adaptive Control and Mobile Robotics towards maintaining the Sustainable Development and Smart Planning and management of the future technologies. It is aimed at the knowledge generated from the integration of the different data sources related to a number of active real-time applications in supporting the smart planning and enhance and sustain a healthy environment. The conference also covers the rise of the digital health, well-being, home care, and patient-centred era for the benefit of patients and healthcare providers; in addition to how supporting the development of a platform of smart Dynamic Health Systems and self-management.

Download or read book Absorption Chillers and Heat Pumps written by Keith E. Herold and published by CRC Press. This book was released on 2016-04-21 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significantly revised and updated since its first publication in 1996, Absorption Chillers and Heat Pumps, Second Edition discusses the fundamental physics and major applications of absorption chillers. While the popularity of absorption chillers began to dwindle in the United States in the late 1990's, a shift towards sustainability, green buildin

Download or read book Energy Research Abstracts written by and published by . This book was released on 1988 with total page 1684 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2008 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theses on any subject submitted by the academic libraries in the UK and Ireland.

Download or read book Advanced Research on Electronic Commerce Web Application and Communication written by Gang Shen and published by Springer. This book was released on 2011-03-18 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-volume set CCIS 143 and CCIS 144 constitutes the refereed proceedings of the International Conference on Electronic Commerce, Web Application, and Communication, ECWAC 2011, held in Guangzhou, China, in April 2011. The 148 revised full papers presented in both volumes were carefully reviewed and selected from a large number of submissions. Providing a forum for engineers, scientists, researchers in electronic commerce, Web application, and communication fields, the conference will put special focus also on aspects such as e-business, e-learning, and e-security, intelligent information applications, database and system security, image and video signal processing, pattern recognition, information science, industrial automation, process control, user/machine systems, security, integrity, and protection, as well as mobile and multimedia communications.

Download or read book Chemical Engineering and Chemical Process Technology Volume II written by Ryzhard Pohorecki and published by EOLSS Publications. This book was released on 2010-11-30 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical Engineering and Chemical Process Technology is a theme component of Encyclopedia of Chemical Sciences, Engineering and Technology Resources in the global Encyclopedia of Life Support Systems (EOLSS), which is an integrated compendium of twenty Encyclopedias. Chemical engineering is a branch of engineering, dealing with processes in which materials undergo changes in their physical or chemical state. These changes may concern size, energy content, composition and/or other application properties. Chemical engineering deals with many processes belonging to chemical industry or related industries (petrochemical, metallurgical, food, pharmaceutical, fine chemicals, coatings and colors, renewable raw materials, biotechnological, etc.), and finds application in manufacturing of such products as acids, alkalis, salts, fuels, fertilizers, crop protection agents, ceramics, glass, paper, colors, dyestuffs, plastics, cosmetics, vitamins and many others. It also plays significant role in environmental protection, biotechnology, nanotechnology, energy production and sustainable economical development. The Theme on Chemical Engineering and Chemical Process Technology deals, in five volumes and covers several topics such as: Fundamentals of Chemical Engineering; Unit Operations – Fluids; Unit Operations – Solids; Chemical Reaction Engineering; Process Development, Modeling, Optimization and Control; Process Management; The Future of Chemical Engineering; Chemical Engineering Education; Main Products, which are then expanded into multiple subtopics, each as a chapter. These five volumes are aimed at the following five major target audiences: University and College students Educators, Professional practitioners, Research personnel and Policy analysts, managers, and decision makers and NGOs.

Download or read book Solar Cooling Technologies written by Sotirios Karellas and published by CRC Press. This book was released on 2018-10-03 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar Cooling Technologies presents a detailed study of the potential technologies for coupling solar energy and cooling systems. Unifies all the various power based solar techniques into one book, investigates tri-generation schemes for maximization of cooling efficiency, especially for small scale applications and offers direct comparison of all possible technologies of solar cooling Includes detailed numerical investigations for potential cooling applications

Download or read book Refrigeration Systems and Applications written by Ibrahim Din¿er and published by John Wiley & Sons. This book was released on 2017-03-23 with total page 990 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definitive text/reference for students, researchers and practicing engineers This book provides comprehensive coverage on refrigeration systems and applications, ranging from the fundamental principles of thermodynamics to food cooling applications for a wide range of sectoral utilizations. Energy and exergy analyses as well as performance assessments through energy and exergy efficiencies and energetic and exergetic coefficients of performance are explored, and numerous analysis techniques, models, correlations and procedures are introduced with examples and case studies. There are specific sections allocated to environmental impact assessment and sustainable development studies. Also featured are discussions of important recent developments in the field, including those stemming from the author’s pioneering research. Refrigeration is a uniquely positioned multi-disciplinary field encompassing mechanical, chemical, industrial and food engineering, as well as chemistry. Its wide-ranging applications mean that the industry plays a key role in national and international economies. And it continues to be an area of active research, much of it focusing on making the technology as environmentally friendly and sustainable as possible without compromising cost efficiency and effectiveness. This substantially updated and revised edition of the classic text/reference now features two new chapters devoted to renewable-energy-based integrated refrigeration systems and environmental impact/sustainability assessment. All examples and chapter-end problems have been updated as have conversion factors and the thermophysical properties of an array of materials. Provides a solid foundation in the fundamental principles and the practical applications of refrigeration technologies Examines fundamental aspects of thermodynamics, refrigerants, as well as energy and exergy analyses and energy and exergy based performance assessment criteria and approaches Introduces environmental impact assessment methods and sustainability evaluation of refrigeration systems and applications Covers basic and advanced (and hence integrated) refrigeration cycles and systems, as well as a range of novel applications Discusses crucial industrial, technical and operational problems, as well as new performance improvement techniques and tools for better design and analysis Features clear explanations, numerous chapter-end problems and worked-out examples Refrigeration Systems and Applications, Third Edition is an indispensable working resource for researchers and practitioners in the areas of Refrigeration and Air Conditioning. It is also an ideal textbook for graduate and senior undergraduate students in mechanical, chemical, biochemical, industrial and food engineering disciplines.

Download or read book Research and Development Progress Report written by United States. Office of Saline Water and published by . This book was released on 1965 with total page 978 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Solar Energy Heat Pump Systems for Heating and Cooling Buildings written by Stanley Francis Gilman and published by . This book was released on 1976 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaporator Performance Under Frosted Conditions and Evaluation of Heat Mass Transfer in a Domestic Refrigerator written by Cemil İnan and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study , understanding of how frost accumulates on evaporator surfaces and affects the heat transfer , airside pressure drop, and refrigerator performance are investigated. In order to make a realistic model of evaporator and simulate the refrigerator performance changes while more frost was deposited on the surfaces of evaporator, heat and mass transfer mechaisms of a refrigerator cabinet were also studied. The study was made in five individual chapters. After a short introduction in Chapter-l, in the Chapters 2 and 3 open door heat and mass transfer analysis and experimental study were made. In Chapter-4, the mathematical model of air distribution system was introduced. Finally in Chapter-5, the mathematical model of evaporator was given. Solvers for all models that were developed in the chapters from 2 to 5 were written in the EES environment. Results of the studies are surnrnarized in chapter basis below . Chapter-2; a physİcal model for estimatİng the cabinet flow and heat transfer rates occuring when door is opened were introduced. Model was based on the momentum and energy equations for two-dimensional flow in Cartesian coordinates. The model includes effect of shelves, which changes from none to three, in all possible combinations. Verification was made by using the experimental measurements, and flow visualization techniques. Experimental study was made on a commercially available domestic refrigerator cabinet. Transient velocity and temperature profiles were measured along the height of the cavity opening. Results of open door studies were summarized by set of equations that shows the parameters contributing to the flow and heat transfer. To solve these coupled equations, a solver was developed in EES environment. It was found that in an empty cabinet (without shelf) the inflow area was larger then the outflow area. This shows that the flow is accelerating along with the cabinet height. The maximum air velocity was measured at a point very close to bottom wall. Flow regimes in an open cavity were classified as three characteristic periods starting right after the door opening. Those were initial transient period (0 to 7-10 seconds), transition period (7 -1 0 to 20 seconds ), and quasi-steady period, ( after 20 seconds ). During the first period, one volumetric air exchange is established, and both inlet and outlet velocities are high. After one volumetric air exchange, the flow is mainly driven by wall temperatures. As wall temperature increases, velocity decreases. The conveciİon heat transfer coefficient decreases when the number of shelves are increased. Experimental studİes showed that, it was acceptable to take wall temperatures constant for the first 20 seconds of door opening. The model results and experimental results agreed within the error levels of +/-10% for wall temperatures above 3 C, and+/- 30% for below 3 C. Chapter-3; by help of heat and mass transfer analogy, the latent and sensible (convective + radiation ) heat transfer, and mass transfer percentages in the total cabinet load were analyzed. According to this study , the daily heat gain of the cabinet for 20 times of door opening was increased by 15% to 32% for 30% RH to 1OO%RH respectİvely .In these analysis; ambient temperature was 25 C, wall temperature was 5 C, duration of each door opening was 20 seconds, number of the shelves were three, and shelves were equally spaced. The percentages of heat gain coming from door openings will, of course, be increased in the refrigerators having better insulaion. The latent and sensible loads caused by door opening were found to be equal for ambient conditions of 60% RH. The breakdown of modes of heat transfer that occur during door opening period is given below .The conduction heat transfer from cabinet walls during the 20 s of door opening is neglected. Radiation heat transfer: 8.2% Convection (sensible) heat transfer: 42% Latent heat transfer: 49.8% Chapter-4; a mathematİcal model for analyzing the air distribution system of a nofrost refrigerator was developed. Model was based on conservation of momentum and the first law of the thermodynamics. A solver was developed in EES environment. A commercial refrigerator cabinet was used to compare the model result with the measurements and the CFD analysis. The estimated airflow rate, and static pressure were found compatible to measurements with less then 3% error. The difference between model and CFD analysis were maximum 15%. The results were found promising, and the solver could be used effectively in the areas of initial design of the air distribution system, selection of a fan, and balancing the airflow rates distributed between compartments of refrigerator .Chapter-5; a refrigerator evaporator, tube on sheet type, was analyzed. Calculatİon procedure for obtaining the heat and mass transfer characteristics of the refrigerator evaporators that operate under dry and frosting conditions has been introduced. A mathematical model that was used to obtain heat transfer coefficients, and pressure drop characteristics was developed. The solver is capable of calculating the frost thİckness, density , frost mass, overall heat transfer coefficient, exit temperature and humidity, and pressure drop values for each individual tube row for quasi-steady time steps. . As it is indicated in the literature, during the frost formation, both thickness and density increase with time. This phenomenon is due to the fact that some percentage of mass transfer goes to increase the thickness, and the remaining goes to increase density (this process can be called as densification of the frost). These percentages are found very important parameters on calculation of evaporator characteristics. Unlike the literature, where densification is calculated by using the analytical methods, these percentages were chosen as constant parameters. According to the study, when the densification ratio was increased from 0.2 to 0.5, the pressure drop decreased approximately three times, the accumulated frost mass increased 4%, and the heat transfer coefficient increased 5% (at the end of 12 hours operation time). By taking the densification ratio equal to 0.3, the effect of following parameters were investigated, the operation time is 12 hours. Effect of the evaporation temperature: Increasing the evaporator temperature from -35 C to -25 C results; 10% decrease on heat transfer coefficient, half of pressure drop, and 5 times lower frost mass. Effect of the airflow rate: When the flow rate is increased from 5 l/s to 25 l/s, the UA value increases 3 times, pressure drop ncreases more than 10 times, and frost mass increases 3.5 times. Simulation of the real refrigerator case was studied. Airflow rate of each time step was calculated by using the updated pressure drop values of whole air distribution system and fan characteristic curves, as well. In order to do this, the solver developed in chapter-4 was integrated to solver of Chapter-5. Evaporator UA value and pressure drop values were obtained for three different inlet air relative humidity values. Accordİng to this study , UA showed first increasing trend until a peak value was reached, then relatively sharp decreasing trend that ended when the evaporator was completely blocked. On the other hand, pressure drop calculations showed exponentially increasing trend all the time. In addition, the pressure drop and frost thickness values were increased more rapidly for higher relative humidity values. Complete evaporator blockage is occurred after 45 hours and 110 hours of continuous operation time for inlet humidity values of 80%, and 50%, respectİvely . In oroer to show how all individual models can be used in calculation of quasi-steady temperature and humidity values of cabinet air, a sample run in a freshfood cabinet was made. Results of the evaporator model was compared to the experimental studies of Seker (1999). The estimated UA value was found 10% higher than the experimental value. However, the calculated pressure-drop value was 25% lower than the measured value. It should be noted that the experimental study was obtained for only 2 hours of operatİon time, therefore the model results will be reexamined after having more experimental results.

Download or read book Recent Trends in Mechanical Engineering written by Ambrish Maurya and published by Springer Nature. This book was released on 2023-06-07 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the select papers presented at the International Conference on Progressive Research in Industrial & Mechanical Engineering (PRIME 2021), held at the National Institute of Technology (NIT) Patna, India. The book discusses various aspects related and relevant to core areas of mechanical engineering including engineering design, production engineering, industrial engineering, automobile engineering, thermal and fluids engineering, mechatronics, control and robotics and other inter-disciplinary emerging topics for potential use in a spectrum of applications. The book will be a valuable reference for students, researchers and professionals interested in mechanical engineering and allied fields.