Download or read book Frosting and Defrosting of Air Coils written by Per Fahlén and published by . This book was released on 1996 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frosting adversely affects the performance of air-coils under adverse conditions. This report surveys the literature in this field with applications such as air-source heat pumps, refrigeration cooling and freezing coils, and heat recovery ventilators. Since the heat and mass transfer characteristics of a coil will significantly influence the process of frosting, many references pertain to the dry and wet heat transfer of finned-tube air-coils. Furthermore, the change in pressure drop and air flow caused by frosting is a major factor in determining the drop in coil capacity. Therefore the survey also lists references to coil pressure drop. The report contains a literature survey part, a technical index and an alphabetical author index. The survey part discusses some of the most important references based, among other things, on the frequency with which they appear in the reference lists of other authors. In the technical index, references are sorted according to their relevance on topics such as heat and mass transfer, frosting, defrosting, defrost control, as well as standards and test methods. Finally, the alphabetical author index simply gives all the references in alphabetical order according to the name of the first author. A total of 738 references are listed. In some cases, however, the references may seem rather peripheral to the subject of frosted coils. This is particularly the case regarding practical experience. Such information is often subordinate to a lot of general operational information regarding refrigeration and heat pump equipment. Nonetheless, such references are worthwhile for the researcher to consider since they provide an important link between the engineering and the research communities.
Download or read book Frosting and Defrosting of Air coils written by Per Fahlén and published by . This book was released on 1996 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frosting of air-coils is an important factor in the design and operation of air-source heat pumps, heat recovery ventilators, cooling and refrigeration equipment etc. This report presents results from laboratory testing of two brine-cooled air-coils under frosting conditions. The coils have the same number of plane, continuos fins, 4 tube rows with 12 tubes in each row, tube spacing of 50 mm and fin spacing of 3 and 6 mm respectively. The original purpose of the test program was to compare various possible indicators of coil frosting and to analyze the possible effects of different control strategies on coil capacity and the COP of the system (the analysis will be presented in a separate report). Tests involved inlet air temperatures of -7 and +2 degrees Celsius, variation of humidity between 70 and 100 % RH (including simulated rain), velocities in the range 1 to 4 m/s, and specific cooling loads from 50 to 150 W/m2. Test results include variations due to frosting of e.g. cooling capacity, COP, air flow and pressure drop, fan power, air outlet temperature and humidity, coil temperature, frost mass, and frosting time. Results also include the subsequently required defrost time, defrost energy and collected mass of defrost water. The frosting process was interrupted when the air flow had decreased to 30 % of the original value with a non-frosted coil. The results clearly show the advantage of demand controlled defrosting with variations in frosting time between 2 h with high humidity/high specific cooling load up to, for practical purposes, infinite frosting times with low humidity/low specific cooling load. The accumulated frost mass during one frosting cycle varied from less than 0.02 kg/m2 up to approximately 0.4 kg/m2.
Download or read book Frosting and Defrosting of Air coils written by Per Fahlén and published by . This book was released on 1996 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Defrosting for Air Source Heat Pump written by Mengjie Song and published by Woodhead Publishing. This book was released on 2019-06-01 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Defrosting for Air Source Heat Pumps: Research, Analysis and Methods presents a detailed analysis of the methods, processes and problems relating to defrosting, a necessary requirement to maintain the performance of ASHP units. Readers will gain a deeper understanding of control strategies and system design optimization methods that improve the performance and reliability of units. The book discusses the most recent experimental and numerical studies of reverse cycle defrosting and the most widely used defrosting method for ASHP. Techno-economic considerations are also presented, as is the outlook for the future. This book is a valuable resource for research students and academics of thermal energy and mechanical engineering, especially those focusing on defrosting for ASHP, heating, ventilation and energy efficiency, as well as engineers and professionals engaged in the development and management of heat pump machinery. Includes MATLAB codes that allow the reader to implement the knowledge they have acquired in their own simulations and projects Discusses experimental and numerical studies to provide a well-rounded analysis of technologies, methods and available systems Presents techno-economic considerations and a look to the future
Download or read book FROSTING AND DEFROSTING BEHAVIOUR OF OUT DOOR COILS OF AIR SOURCE HEAT PUMPS FINAL REPORT FIGURES written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Frosting and Defrosting Behaviour of Outdoor Coils of Air source Heat Pumps written by J. W. J. Bouma and published by . This book was released on 1981 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Frosting and Defrosting Behaviour of Outdoor Coils of Air source Heat Pumps written by Commission of the European Communities. Directorate-General for Energy and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Frosting and Defrosting Behaviour of Outdoor Coils of Air source Heat Pumps written by J. W. J. Bouma and published by . This book was released on 1981 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Defrosting for Air Source Heat Pump written by Mengjie Song and published by Woodhead Publishing. This book was released on 2019-05-16 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Defrosting for Air Source Heat Pumps: Research, Analysis and Methods presents a detailed analysis of the methods, processes and problems relating to defrosting, a necessary requirement to maintain the performance of ASHP units. Readers will gain a deeper understanding of control strategies and system design optimization methods that improve the performance and reliability of units. The book discusses the most recent experimental and numerical studies of reverse cycle defrosting and the most widely used defrosting method for ASHP. Techno-economic considerations are also presented, as is the outlook for the future. This book is a valuable resource for research students and academics of thermal energy and mechanical engineering, especially those focusing on defrosting for ASHP, heating, ventilation and energy efficiency, as well as engineers and professionals engaged in the development and management of heat pump machinery. - Includes MATLAB codes that allow the reader to implement the knowledge they have acquired in their own simulations and projects - Discusses experimental and numerical studies to provide a well-rounded analysis of technologies, methods and available systems - Presents techno-economic considerations and a look to the future
Download or read book Numerical and Experimental Study of the Influence of Frost Formation and Defrosting on the Performance of Industrial Evaporator Coils written by Nawaf Faisal Aljuwayhel and published by . This book was released on 2006 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Frosting and Defrosting Behaviour of Outdoor Coils of Air source Heat Pumps written by Commission of the European Communities and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Frosting for Air Source Heat Pumps written by Mengjie Song and published by Elsevier. This book was released on 2024-11-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frosting for Air Source Heat Pumps: Research, Case Studies, and Methods provides a comprehensive accounting of the latest research, analysis, and modeling methods for limiting frosting and maximizing efficiency. The book begins by outlining the fundamentals of frosting mechanisms, including the condensation and freezing of water droplets. It then provides a wide range of case studies that showcase a variety of surfaces, conditions, and energy generation technologies. Finally, the last chapters demonstrate modeling and analysis of frosting operation before laying out critical considerations for designing a frost control strategy in ASHPs.Building on the theory and studies contained in the author's previous work Defrosting for Air Source Heat Pumps, this book provides essential and advanced information for understanding and controlling frosting for these sustainable energy sources. - Outlines the fundamentals of frosting mechanisms in different circumstances and on a variety of surfaces - Provides a wide range of real-world case studies, including demonstrations of analysis and modeling in finned tube heat exchangers and ASHPs - Details a huge collection of experimental and numerical data on reverse cycle defrosting, the most common defrosting methods for ASHPs
Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Refrigeration Systems for Cold Storage written by and published by . This book was released on 1986 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Refrigeration Engineering written by and published by . This book was released on 1936 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt: English abstracts from Kholodil'naia tekhnika.
Download or read book The Effect of Surface Wettability on the Defrost Process written by Yang Liu and published by Springer. This book was released on 2018-10-26 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This SpringerBrief presents a recent advancement in modeling and measurement of the effect of surface wettability on the defrost process. Carefully controlled laboratory measurements of the defrosting of cooled surfaces are used to reveal the effect of surface wetting properties on the extent and speed of frost removal by melting or slumping. The experiments are accompanied by visualization of frost removal at several defrosting conditions. Analysis breaks the defrost process into three stages according to the behavior of the meltwater. Surface wetting factors are included, and become significant when sufficient meltwater accumulates between the saturated frost layer and the surface. The book is aimed at researchers, practicing engineers and graduate students.
