Academic literature on the topic 'Traditional refrigerator'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Traditional refrigerator.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Traditional refrigerator"
1
Petrosov, S. P., M. A. Lemeshko, A. V. Kozhemyachenko, and S. E. Bashnjak. "Methods of calculation of energy losses of the refrigerator when opening its doors." MATEC Web of Conferences 215 (2018): 01018. http://dx.doi.org/10.1051/matecconf/201821501018.
Full textAbstract:
The problem of energy supply and the problem of energy efficiency of energy consumers are global problems. In the modern world, scientists pay much attention to the tasks of creating new and improving traditional sources of electricity. The tasks of increasing the energy efficiency of electricity consumers remain relevant in the global economy. One of the relatively capacious energy consumers is the Park of refrigerators, household and commercial purposes, which are also being improved in order to increase their energy efficiency. Modernization and improvement of household and commercial refrigerators include the task of designing and using more efficient refrigerators. Energy consumption of compression refrigerators, along with other operational factors, depends on the processes of heat exchange and mass transfer of air from internal chambers to the ambient air. When the doors of the refrigerator chambers are opened, the cooled air in the chambers is replaced with the warmer air of the environment. This process causes the cost of operation of the refrigeration machine and characterizes its energy consumption. In order to minimize this power consumption, knowledge of the process of cool air outflow of their open refrigerator chambers is required. Currently, this process is poorly understood. The article presents an approach to the description of the process of motion of the cooled air from the refrigerator chamber, the main assumptions necessary for the construction of a mathematical model of this process are given, and a method for calculating the heat in the refrigerator chambers associated with the replacement of the cooled air with the ambient air inside the chambers is proposed. The method is based on the laws of gas dynamics, supplemented by some experimental studies. In particular, the well — known Navier-Stokes equation is used as the initial basis. This equation supplemented by the continuity equation of the air flow and other functional dependencies. As a result of mathematical transformations and arguments about the physics of the mass transfer process, finite equations are obtained, which allow describing both the performance of the cooled air flow and the amount of heat introduced into the chambers by external warm air. Mathematical dependences are developed for calculation of parameters of motion of a stream of the cooled air and heat inflows, thus the temperature of ambient air and temperature in chambers of the refrigerator are considered. The results of the research will be useful in the design of new refrigerating machines with reduced energy consumption.
2
Olomu, J. M. "Effects of Traditional Methods of Storage on Egg Quality." Nigerian Journal of Animal Production 2, no. 2 (January 15, 2021): 182–87. http://dx.doi.org/10.51791/njap.v2i2.2155.
Full textAbstract:
THE effectiveness of using maize starch, warm water, cold water, groundnut oil, palm oil and cold storage [refrigerator] in preserving the quality of eggs was studied. Groundnut oil, palm oil and cold storage were equally effective in preserving the quality of eggs while maize starch, cold water and warm water were found ineffective. The effectiveness of palm oil and groundnut oil was further enhanced when the oil-treated eggs were stored in the refrigerator for four weeks. Treatment with groundnut oil for one minute before storage for four weeks was considered the preferred method of preserving the quality of eggs.
3
Zhao, Jia Quan, Da Peng Hu, Pei Qi Liu, Feng Xia Liu, and Jin Ji Gao. "Thermodynamic Analysis a Novel Wave Rotor Refrigeration Cycle." Advanced Materials Research 805-806 (September 2013): 537–42. http://dx.doi.org/10.4028/www.scientific.net/amr.805-806.537.
Full textAbstract:
As a novel generation of thermal separators, the Wave rotor refrigerator (WRR) has replaced the traditional pressure-wave thermal separator. However, the isentropic refrigeration efficiency still needs to be improved compared with expander. A novel WRR system cycle was built and the system performance was thermal analyzed under various parameters, such as expansion efficiency or compression efficiency of wave rotor. The results are used to compare with the traditional WRR system. It is shown that the advantage provided by this novel cycle over the traditional WRR is an expansion process and a compression process is integrated into one unit, with a higher energy transfer efficiency and simple structure. The isentropic refrigeration efficiency of this novel cycle can be more than twice of the traditional WRR under the pressure ratio of 1.1. The experimental works are carrying out.
4
Gao, Wei Zeng, Yue Sheng Gu, and Yan Li Zhu. "Design for Refrigerator Assembly." Advanced Materials Research 538-541 (June 2012): 2932–36. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.2932.
Full textAbstract:
In refrigerator industry, takt time becomes shorter with the growth of refrigerator production, product configurations become more diverse with the increase of customizing requirements, traditional data acquisition methods and manufacturing resource identification methods cannot meet the need of manufacturing execution system (MES) in job shop scheduling, work in process (WIP) tracking, rapid response of process control and so on. As an automatic identification technology, Radio Frequency Identification (RFID) can be applied to bridge the gap between physical flow of product/part and information flow in enterprise application system due to its characteristics such as automatic identification, long-distance reading, and non-line-of sight. Based on this characteristic, this paper design a real-time MES (RT-MES) for refrigerator production and successfully implements this system based on the actual situation of JAC.
5
Duan, Liqiang, and Zhen Wang. "Performance Study of a Novel Integrated Solar Combined Cycle System." Energies 11, no. 12 (December 4, 2018): 3400. http://dx.doi.org/10.3390/en11123400.
Full textAbstract:
Based on a traditional integrated solar combined cycle system, a novel integrated solar combined cycle (ISCC) system is proposed, which preferentially integrates the solar energy driven lithium bromide absorption refrigeration system that is used to cool the gas turbine inlet air in this paper. Both the Aspen Plus and EBSILON softwares are used to build the models of the overall system. Both the thermodynamic performance and economic performance of the new system are compared with those of the traditional ISCC system without the inlet air cooling process. The new system can regulate the proportions of solar energy integrated in the refrigerator and the heat recovery steam generator (HRSG) based on the daily meteorological data, and the benefits of the solar energy integrated with the absorption refrigeration are greater than with the HRSG. The results of both the typical day performance and annual performance of different systems show that the new system has higher daily and annual system thermal efficiencies (52.90% and 57.00%, respectively), higher daily and annual solar photoelectric efficiencies (31.10% and 22.31%, respectively), and higher daily and annual solar photoelectric exergy efficiencies (33.30% and 23.87%, respectively) than the traditional ISCC system. The solar energy levelized cost of electricity of the new ISCC system is 0.181 $/kW·h, which is 0.061 $/kW·h lower than that of the traditional ISCC system.
6
Li, Zhi Hai, Yan Liu, and Yuan Zhong. "Piston Optimization Design of Linear Compressor for Refrigerator." Applied Mechanics and Materials 552 (June 2014): 51–54. http://dx.doi.org/10.4028/www.scientific.net/amm.552.51.
Full textAbstract:
A linear compressor does not have a crank mechanism to drive the piston and is driven directly by a linear motor, which has a higher electrical efficiency than a traditional rotary induction motor. So it becomes an important research direction of future refrigerator compressor. This paper aims to optimize the structure of piston and cylinder of linear compressor to reduce friction loss and improve compressor’s efficient. From the design analysis and experiment, the structure and material of piston and cylinder are improved. All the support points are on the piston. Material of cast iron is used for piston and cylinder. And phosphate processing is performed on the surface. Experiments verified that the changes can reduce wear and improve the efficiency of the compressor.
7
Trifunski, Svetlana, and Dorina Ardelean. "Determination of the antioxidant activity of Ficus carica aqueous extract." Zbornik Matice srpske za prirodne nauke, no. 122 (2012): 25–31. http://dx.doi.org/10.2298/zmspn1222025t.
Full textAbstract:
The aim of this study was to examine the antioxidant activity of water extracts from fig leaf. Water extracts were prepared according to traditional medicine. The antioxidant activity of the extracts was spectrophotometrically determined. Using the potassium permanganate colorimetric method it was found that the water extract that was maintained at the refrigerator had lower antioxidant activity than extract that was maintained at the room temperature.
8
TRZECIAK, M. A., and W. MEISSNER. "Stability of HCT, HGB and RBC values in the Mute Swan (Cygnus olor) blood stored at 4°c and 24°c differs between traditional and multi-parameter automated methods." Journal of the Hellenic Veterinary Medical Society 69, no. 3 (October 10, 2018): 1141. http://dx.doi.org/10.12681/jhvms.18887.
Full textAbstract:
The objective of this study was to evaluate the influence of time of sample storage, method of analysis, and storage temperature on stability of HCT, HGB, and RBC in avian blood samples. Blood samples from mute swans were stored at 24°C or 4°C. Analyses of HCT, HGB, and RBC were carried out after 5 and 25 hours after collection of blood using both traditional and Cell-Dyn 3700 analyzer methods. Storage temperature had no significant influence on HCT, HGB, and RBC values of mute swan blood. However hematological parameters obtained by the traditional method were significantly lower than the results from the analyzer. Time of storage had a significant influence on values obtained traditionally for HCT, HGB, and RBC, but did not affect results that were obtained by the multi-parameter automated method. These results indicate that the mute swan blood can be stored at both room and refrigerator temperature. However, the analysis should be performed as soon as possible, especially in the case of traditional methods. Reference intervals for this species should always include information about the method used for hemogram determination and time elapsed since the blood collection.
9
Longo, Giovanni A., Giulia Righetti, and Claudio Zilio. "Development of an Innovative Raw Milk Dispenser Based on Nanofluid Technology." International Journal of Food Engineering 12, no. 2 (March 1, 2016): 165–72. http://dx.doi.org/10.1515/ijfe-2015-0127.
Full textAbstract:
Abstract This paper presents the comparative analysis of a traditional raw milk dispenser and an innovative prototype based on nanofluid technology. The traditional raw milk dispenser consists of an off-the-shelf upright air-cooled refrigerator sold on the market, whereas the innovative prototype presents a tank equipped with a serpentine tube jacket operated with Al2O3–ethylene glycol aqueous solution nanofluid. The systems are experimentally analysed in the ambient temperature range of 19–35°C to evaluate the energy performance and the temperature control of the milk tank. The innovative prototype is demonstrated to be superior from the point of view of both energy saving and food safety. In fact, the innovative prototype exhibits a 63–70% energy saving with respect to the traditional one. Furthermore, the prototype distributor is able to reach the “safe” temperature of 4°C in about half of the time required by traditional system and it keeps the milk always in the “safe” temperature range 2–3°C, while the traditional distributor displays locally milk temperature higher than 4°C.
10
Ünver, Naciye. "Storage stability and fatty acid composition of Sanliurfa butterfat." Mljekarstvo 71, no. 2 (March 16, 2021): 124–31. http://dx.doi.org/10.15567/mljekarstvo.2021.0205.
Full textAbstract:
In this research, Sanliurfa butterfat, collected from local small-sized dairy plants located in Karacadağ Region of Sanliurfa, were stored at two different temperatures (4 and 20 °C) for 12 months. The butterfat samples have been analysed to determine some biochemical parameters (free fatty acids, acid value, peroxide value, induction time, and pH) and fatty acid composition on the 1st, 30th, 90th, 120th, 180th, 270th and 360th days of storage. The mean value of free fatty acids, acid value and peroxide value of the butterfat stored in refrigerator conditions (4 °C) were lower, and the induction time was higher than the butterfat stored at room temperature (20 °C) (P<0.05). Furthermore, the acid value, free fatty acids value, C16:1, C17:1, C18:2n6c and MUFA of the butterfat increased significantly during the storage period (P<0.05). The ratio of saturated fatty acid of the butterfat decreased during the storage (P<0.05). According to the results of free fatty acids, traditional Sanliurfa butterfat at room temperature (20 °C) could be stored safely for a maximum of 3 months, while this period could be up to 6 months for the butterfat stored at refrigerated temperature (4 °C).
Dissertations / Theses on the topic "Traditional refrigerator"
1
Bashardanesh, Mohammad. "Historic Persian buildings and structures: windwards, refrigerators and structural foundations." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Find full textAbstract:
Architecture in life is the light of the culture in any society and closely relates with historical, political, economic and social aspects of the society. Persian architecture and building construction should be properly examined from the depths of the history of this ancient land. Persian architecture goes back to six centuries before Christ and it has over 6000 years of continuous history. Since then ever, architecture has been related to various issues, especially religious, and has developed and evolved for centuries.
Persian architecture has features that in comparison with other countries are of particular value. Properties such as good design, precise calculations, the correct form of coverage, compliance with technical and scientific issues in the building, high balconies, tall pillars and the various decorations that each of them represent the magnificent of Persian architecture.
This study assumes that architecture and building construction are the full manifestation of human culture, and focus on some of the important elements in traditional Persian architecture: windwards, traditional refrigerators and foundations.
2
Sandoval, Riveros André Jancarlos, and Martinez Rafael Antonio Vera. "Factores que impactaron en el comercio de espárragos, frescos o refrigerados (0709200000) entre Perú y Reino Unido desde el año 2012 hasta el 2017." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626109.
Full textAbstract:
La presente investigación tiene como objetivo analizar los diferentes efectos que impactaron en el comercio de Espárragos frescos o refrigerados de Perú con el Reino Unido durante los años 2012 al 2017, siendo estos efectos tanto públicos como del sector privado agroexportador.
Por tal motivo, se precisó investigar y analizar el histórico de la desgravación arancelaria que se va dando a lo largo de los años gracias a los acuerdos comerciales que existen entre Perú y diferentes mercados con relación a los productos agroindustriales. Pero, haciendo énfasis y más dirigido al caso de los Espárragos frescos o refrigerados hacia el Reino Unido durante los años.
Asimismo, se analizó el impacto de ciertos factores medio ambientales sobre las cosechas de espárragos en el territorio peruano y su consecuencia con las exportaciones a al mercado de Reino Unido. De igual manera cómo influye la mano de obra con respecto a efectos sociales al momento de analizar su relevancia en los tiempos cruciales de cultivo y cosecha.
Además, al tratar temas políticos y económicos, se llevó a investigar y analizar sucesos políticos trascendentales que logran tener un impacto en las relaciones internacionales entre mercados, así como análisis económico de un mercado en específico.
Bajo este fin, se recopiló y relacionó información proveniente de ciertas herramientas metodológicas como datos estadísticos de SUNAT, Veritrade y MINCETUR, información pública y entrevistas a personas con conocimientos en temas relacionados al comercio del sector agroexportador, relaciones internacionales, comercio exterior y derecho público internacional.The main object of this research is to analyze the different effects that impacted the trade of fresh or chilled asparagus from Peru to the United Kingdom during the years 2012 - 2017, with both public and private agro-exporter effects. For this reason, it was necessary to investigate and analyze the history of tariff reduction that is taking place over the last years thanks to trade agreements that exist between Peru and different markets in relation to the agro-industrial products. But, making emphasis in the case of fresh or chilled asparagus towards the United Kingdom over the years. Likewise, the impact of certain environmental factors on the asparagus crops in the peruvian territory and its impact in the exports to the United Kingdom market was analyzed. In the same way, how handmade labor influences social effects, analyzing their relevance in the crucial times of cultivation and harvest. In addition, when dealing with political and economic issues, it was carried out to investigate and analyze transcendental political events that manage to have an impact on international relations between markets, as well as economic analysis of a specific market. To this end, information was collected and related from certain methodological tools such as statistical data from SUNAT, Veritrade and MINCETUR, public information and interviews with people with knowledge of issues related to trade in the agro-export sector, international relations, foreign trade and international public law.
Tesis
3
Ou-Yang, Sen, and 歐陽森. "The Process of Traditional Refrigerated Warehousing Transforming into Cold Chain Distribution Center - A Case Study of RM Company." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/23raez.
Full textAbstract:
碩士國立高雄海洋科技大學
供應鏈管理研究所
104
With the popularity of cold chain logistics, the Ministry of Economics has been promoting “Three Industries, Four Reforms” policy, showing the focus of the government for the cold chain development. On August, 2016, the government checked out some cold chain distribution centers and some company didn’t pass it. These years, there has been a growing consumer awareness of cold chain food safety and quality in Taiwan. The cold chain is a safe low-temperature supply chain system that involves all of the means to ensure a constant temperature and quality for a product, from the time it is manufactured until the time it is warehoused by wholesalers and retailers or purchased by consumers. However, despite the advance of technology, most of the refrigerated warehousing companies in Chien Chen Fishing Harbor still suffer from the shortage of software and equipment, which will easily cause the problem of “out of the cold chain.” Under this circumstance, the process of the logistics fails to maintain a constant demanded temperature and further influence the quality as well as safety of the product, and is unable to satisfy the needs of the cold chain distribution. Therefore, traditional refrigerated warehousing industry will have to constitute appropriate global logistics strategies and gradually transform into modernized cold chain distribution centers for future development. The case study method will be adopted to conduct participated observation with RM Company during the process of transforming into cold chain distribution center. Furthermore, the researcher analyzed the collected data from the company, such as global logistics strategy, capital investment, talent recommendation and the plan of logistics system. The result show that every issue of cold chain distribution center is closely related, and the result also can be helpful for the traditional refrigerated warehousing industry which strategize their global logistics strategy of transformation.
Book chapters on the topic "Traditional refrigerator"
1
"Chapter^>19: Thinking Outside the Traditional Box and Setting Up and Maintaining a Healthy Pantry, Refrigerator, and Freezer." In The Maillard Reaction Reconsidered, 408–15. CRC Press, 2016. http://dx.doi.org/10.1201/b19207-23.
Full text
2
Bertrams, Kenneth, Julien Del Marmol, Sander Geerts, and Eline Poelmans. "A Traditional Industry Switches Gears, ca. 1850–1914." In Becoming the World's Biggest Brewer, 6–49. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198829089.003.0002.
Full textAbstract:
Several inventions completely transformed and revolutionized the ancient craft of brewing in the nineteenth century. Among the most important ones: the introduction of steam in the brewing process, a better understanding of yeast and its working, the invention of artificial refrigeration, the breakthrough of glass production, and the scientification and academization of brewing. Lager, a beer style hitherto confined to central Europe, started to spread and supersede traditional ales, creating opportunities which were grasped by several companies, old and new. One was the Artois brewery from Leuven, an already well-established brewery, with a brewing lineage going back to the 1700s. The Piedboeuf brewery from Jupille, on the other hand, was a newcomer in a brewing business in full transformation. This chapter discusses the roots of the two families and their companies that would come to dominate the Belgian and global beer market.
3
Bibik, Olena, and Oleksandr Popovich. "INCREASING THE EFFICIENCY OF ELECTRIC DRIVES WITH PERIODICAL LOADING BY USING COMPREHENSIVE MATHEMATICAL MODELING MEANS." In Priority areas for development of scientific research: domestic and foreign experience. Publishing House “Baltija Publishing”, 2021. http://dx.doi.org/10.30525/978-9934-26-049-0-31.
Full textAbstract:
The mode of operation of induction motors (IMs) affects their performance. In most cases, motors are optimally designed for steady state operation. When operating in other modes, additional attention is required to the problems of energy efficiency. Induction motors are the most common type of electromechanical energy converters, and a significant part of them operate under conditions of periodic changes in the load torque. The work is devoted to solving the problem of increasing the energy efficiency of asynchronous motors of electromechanical systems with a periodic load, including pumping and compressor equipment. The traditional solution to this problem for compressor equipment is the optimal design of an IM under static conditions, as well as the use of flywheels, the use of an IM with an increased slip value and controlled IM with a squirrel-cage rotor and with frequency converters. In this work, the modes of operation of asynchronous motors with periodic loading are investigated. For this, complex mathematical models are developed in the simulation system. Such models are effective in modeling taking into account periodic load changes: repetitive transient processes, their possible asymmetry and non-sinusoidality, increased influence of nonlinearity of electromagnetic parameters. In complex mathematical modeling, the mutual influence of the constituent parts of the electromechanical system is taken into account. Simulation allowed quantifying the deterioration in energy efficiency under intermittent loading, in comparison with static modes. Criteria for evaluating quasi-static modes have been developed and areas of critical decrease in efficiency have been determined. The paper proposes and demonstrates a methodology for solving this problem. For this purpose, tools have been created for the optimal design of asynchronous motors as part of electromechanical systems with periodic loading. These tools include: complex mathematical models of electromechanical systems with asynchronous motors with periodic load, mathematical tools for determining the parameters of quasi-steady-state modes, the methodology of optimal design based on the criterion of the maximum efficiency of processes under quasi-steady-state modes of operation. The possibilities, advantages and prospects of using the developed mathemati-cal apparatus for solving a number of problems to improve the efficiency of electric drives of compressor and pumping equipment are demonstrated. It is shown that by taking into account quasi-static processes, the use of complex mathematical models for the optimal design of asynchronous motors with a periodic load provides an in-crease in efficiency up to 8 ... 10%, relative to the indicators of motors that are de-signed without taking into account the quasi-static modes. The areas of intense quasi-steady-state modes are determined using the devel-oped criterion. In these areas, there is a critical decrease in efficiency compared to continuous load operation. A decrease in efficiency is associated with a decrease in the amount of kinetic energy of the rotating parts compared to the amount of electromagnetic energy. In connection with the development of a frequency-controlled asynchronous drive of mechanisms with a periodic load, the relevance of design taking into account the peculiarities of quasi-static has increased significantly. For example, a variable frequency drive of a refrigerator compressor or a heat pump can increase energy efficiency up to 40%, but at low speeds, due to a decrease in kinetic energy, the efficiency can decrease to 10 ... 15%, unless a special design methodology is applied. This problem can be solved by using the complex mathematical modeling tools developed in the article.
4
Glivin, Godwin, Mariappan Vairavan, Premalatha Manickam, and Joseph Sekhar Santhappan. "Techno Economic Studies on the Effective Utilization of Non-Uniform Biowaste Generation for Biogas Production." In Anaerobic Digestion in Natural and Built Environments [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98314.
Full textAbstract:
Environmental effects from traditional energy sources and government regulations, necessitate the use of alternative energies like biogas for many uses including drying and refrigeration. Biowaste produced in educational institutions will not be uniform over the year. The non-uniform supply of biowastes, the absence of studies on bio digestion of likelihood biomass, the unreliability of energy from such conversion and the profitability of its usage in most applications are some of the factors to be considered while implementing this technology. In this regard, theoretical and experimental evaluations were carried out to accurately forecast biogas generation capabilities in educational campuses for obtaining biofuels with quantity and efficiency. It is observed that biogas generation with 52 to 58% methane content can be possible during an academic year. The quality of biogas shows that it is appropriate for almost any application. A broader analysis on different types of biogas digesters was conducted for their suitability in academic institutions. The economic benefits are analyzed for incorporating three biogas digesters namely KVIC, Fiber Reinforced Plastic (FRP) type and JANATA. There are some encouraging results to confirm the economic feasibility of biogas plants including positive net present value. Biogas generation with digesters of capacities varying between 25 and 450 cubic meter shows payback periods varies from 3.18 to 7.59 years, which confirms that it is profitable to use digesters in this range of capacities.
Conference papers on the topic "Traditional refrigerator"
1
DeJohn, David W., and Jeffrey S. Vipperman. "Development and Control of “Stiff Drivers” for Thermoacoustic Refrigeration." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41586.
Full textAbstract:
Thermoacoustic refrigerators offer advantages over vapor-compression refrigerators in terms of their inherent mechanical simplicity, lack of chlorofluorocarbon pollutants, and potentially low cost. However, current thermoacoustic refrigerator designs are inhibited by poor efficiency relative to their more conventional counterparts. This paper details attempts to improve the efficiency of a prototype standing-wave thermoacoustic refrigerator through the development of “stiff driver” actuators. Stiff drivers use electronically-driven, lightly-damped structural elements — such as plates or beams — as replacements for traditional drivers. The goal is to reduce the coupling of electromechanical dynamics and acoustical dynamics common to loudspeaker-driven designs while maintaining a cost lower than that of the highly-advanced linear actuators described in some literature. Hofler’s method of using phase-locked loop (PLL) control to track acoustic resonance is altered here in that the output from the PLL is used to modify the geometry of the driver, rather than its driving frequency [1]. Through proper control, the mechanical resonance frequency of the driver is matched to that of the acoustic resonator despite changes in temperature, working fluid, or other factors.
2
Alcock, A. C., S. Balonji, and L. K. Tartibu. "Numerical Analysis of the Performance of an Adjustable Thermoacoustically-Driven Thermo-Acoustic Refrigerator." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11182.
Full textAbstract:
Abstract Thermo-acoustic refrigeration could potentially become an alternative option to current traditional refrigeration systems provided that the issue related to its efficiency is addressed. One of the incentives for developing this technology is the opportunity it establishes with respect to the use of a sustainable heat source to induce cooling. Many existing works have pointed out the relationship between the geometrical configuration of the device and its performance. Mainly, the stack geometry and position have been the focus of these previous works. In this work, a standing-wave ThermoAcoustically-Driven Thermo-Acoustic Refrigerator with an adjustable resonator has been developed. Hence the device is made of two portions, joined with an adjustable duct, namely a simple standing-wave thermo-acoustic engine that converts heat into a sound wave and a simple thermo-acoustic refrigerator where heat pumping takes place. The Design Environment for Low-amplitude ThermoAcoustic Energy Conversion (DELTAEC) was used to model and analyze the influence of the adjustment of the resonator on the cooling performance. Parameters like the temperature difference across the stack, the frequency of the acoustic sound wave generated, the cooling power and the coefficient of performance have been studied. The initial results reported in this study show the possibility to change the performance of practical TADTAR by adjusting the resonator length.
3
Almeida, Antonio Gabriel S., Arthur B. dos Santos, and Ednildo Andrade Torres. "Exergetic Analysis of an Air Conditioning System by Absorption for Transport Vehicles." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-88284.
Full textAbstract:
A traditional vehicular air conditioning system using vapor compression increases fuel consumption by at least 15%, while provoking a reduction in engine power. Whereas an internal combustion engine converts about 30% of the energy into mechanical energy, about 35% is released in the form of exhaust gas and 25% is dissipated through the cooling system, and approximately 50% of the available fuel energy is released as heat to the environment. This heat could be used by an absorption refrigeration system, which requires a high temperature source to provide the vaporization of the refrigerant and decoupling from the absorbent solution. The main objective of this paper is to present a thermodynamic evaluation of the use of heat recovery in internal combustion engines, Diesel cycle, to drive an air conditioning absorption refrigerator for vehicles using the pair water-ammonia. An energy and exergy analysis, applying the First and Second Law of Thermodynamics to the systems involved, is developed in a simulator to evaluate the technical feasibility of using this system to weatherize large vehicles. It identifies the points of the system where the highest irreversibility is found, thus enabling the power focused on reducing such losses. By using asimulation, we hope to determine the basis for the assembly of a prototype vehicular air conditioning system by absorption in transport vehicles.
4
Beiter, Kurt A., Tae G. Yang, and Kos Ishii. "Preliminary Design of Amorphous Products." In ASME 2006 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/detc2006-99680.
Full textAbstract:
This paper addresses the early design and development of amorphous systems. As competitive differentiators, many companies are focusing on amorphous systems comprised of primarily non-physical components, such as software, firmware, and service or business processes. This paper contrasts the development of amorphous systems with that of traditional physical systems. Whereas many tools used in new product development do apply to amorphous systems, the process and the tools need adaptation. The key points are: 1) Modeling of the system using “solution elements” instead of parts, 2) Preliminary concept generation based on use scenarios, and 3) Early consideration of the business model in the context of a complex value chain. The paper presents our proposed 10 step guide to amorphous product development and illustrates it with a “smart refrigerator” example, as well as citing the guide’s deployment in industry.
5
Bonilla García, Diego Ramón, Alejandro Adolfo Lambert Arista, and Ramsés Vega Castellanos. "Design of a Data Acquisition System for Temperatures Monitoring in Thermal Envelope and Water Consumption in Housing." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-65480.
Full textAbstract:
This work describes the design, construction and test of a data acquisition system which performs the real-time monitoring and recording of temperatures in thermal envelope and water consumption in households. This system allows diagnosis and assessment of efficient use of water and a thermal report for electric efficiency purposes. The prototype was subjected to comparative tests with commercial instruments that were used during the project of collaboration with Universidad Autonoma of Baja California and Dennis engineering. The project was developed for energy-efficient housing prototypes for the middle market residential of Mexicali, localized at the state of Baja California in Mexico. At first case, a high gain or loss of heat causes significant increases of important loads as the refrigerator and air conditioning owing to their increment in operation times. Many efficiency energy projects make use of traditional systems for temperature monitoring, whose characteristics exceed the requirements for this type of application and they present economic disadvantages, which can be solved with virtual acquisition systems. Two virtual instruments in LabVIEW were developed which allow real-time acquisition, analysis and recording, with flexible viewing by the user of temperatures and volume of water consumed. Also automatically save data in excel files by specific times. This system can diminish the cost of a conventional temperature monitoring system with 8 acquisition channels approximately in a 50%, keeping precision and accuracy required for this type of applications. The dispositive has the flexibility for monitoring other variables for energy audit, and currently is being tested for climate and electric power parameters.
6
Abdelmessih, Amanie N., Paul W. Bartholomae, Matthew L. Casillas, Rocky E. DeLyon, Joshua F. Flaherty, Bradley D. Goolsby, Moriah M. Langley, et al. "Design of a Magnetic Cooling Device Using Gadolinium Alloy and Permanent Magnets." In ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-7202.
Full textAbstract:
Traditionally, heat pumps and refrigerators utilize the vapor compression cycle to achieve cooling. These vapor compression cycles use hydrochlorofluorocarbons (R134a) as the cycle’s working fluid. This refrigerant contributes to global warming and is expected to be phased out. Consequently, new refrigerants as well as new refrigeration methods need to be developed. The research detailed in this article attempts to implement the magnetocaloric effect of gadolinium alloy in a designed apparatus to lower the temperature of air. Gadolinium alloy has a noticeable magnetocaloric effect within a strong magnetic field (5 T). This research is aimed at producing a noticeable temperature change (2–3 °C) in a relatively smaller magnetic field (1 T) produced with permanent magnets. This work tests the feasibility of magnetic cooling by introducing the design of a magnetic cooling apparatus, using Gadolinium alloy (Gd5Si2Ge2). Small pebbles were used as opposed to a solid plate in order to have an increased surface area to enhance the convection heat transfer process. Permanent magnets were used in the apparatus, to decrease the operating cost. The maximum temperature change encountered in the heat exchanger of the apparatus built was 2.3 °C in a 1 T magnetic field.
7
Copeland, David, and Albert Chan. "Total Power Requirements for Near-Future Refrigerated Systems." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-42344.
Full textAbstract:
As feature dimensions of processors shrink to 100 nanometers and smaller, leakage current becomes a significant part of total power dissipation. The magnitude of power dissipated as leakage current can approach half that of the active current at higher junction temperatures. Leakage current exhibits a strong exponential relationship with temperature. Reduction of junction temperatures from a traditional value of 85 C to a near-ambient value of 25 C can reduce leakage current to a fraction of its usual value, and total power by nearly one-third. To date, refrigeration has been used to increase operating frequency and improve reliability, at the cost of considerable power consumption. At finer feature dimensions, the energy saved by reduction of junction temperature is comparable to that used by the refrigeration system. Realistic values of refrigeration performance, representative of current equipment and refrigerants, are used to perform a case study of a typical near-future processor. Leakage, active and refrigeration power requirements over a junction temperature range from 85 to 25 C are quantified.
8
Ro¨ytta¨, Pekka, Juha Honkatukia, and Teemu Turunen-Saaresti. "Centrifugal Compressor Working Fluids for Refrigeration Cycle." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59150.
Full textAbstract:
A centrifugal high-speed compressor is an effective light weight option to power a refrigeration cycle for air conditioning purposes. Perhaps the most important decision in design is the working fluid selection. Modern high-speed technology makes it possible for the refrigeration compressor to be completely oil free, which considerably broadens the scale of possible working fluids. Furthermore, many traditional fluids have become banned and the industry standard R134a might face the same faith in some European countries because of its relatively high global warming potential. In this study eleven different fluids were studied and compared and R22 was used as a reference. It was found that there are many potential fluids for centrifugal compressors that provide better efficiencies than the most common fluids in use today. The purpose of this study is to initially screen a larger set of candidate fluids for more accurate estimation later on. The fluids are evaluated by the efficiency of the cycle, but also mechanical feasibility and dimensions are considered as light weight of the machinery was an important criterion in design process. The comparison was made with constant evaporation and condensation temperature and fixed cooling power for all the fluids. In selection of the working fluid the safety factors often play a dominant role which was also shortly considered. In our study we found out that for a residential HVAC size cooling cycle there are environmentally friendly fluids with high efficiency leading to feasible mechanical designs with centrifugal compressors.
9
Chen, Qun, and Tian Zhao. "Heat Current Method Based Modeling and Optimization of a Solar-Driven Absorption Chiller for Residential Houses." In ASME 2019 13th International Conference on Energy Sustainability collocated with the ASME 2019 Heat Transfer Summer Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/es2019-3853.
Full textAbstract:
Abstract The utilization of solar energy is attracting rapidly increasing researches due to its many advantages, and an important application is to satisfy the refrigeration demand of residents with the solar-assisted absorption chillers. However, the simple solar-assisted refrigeration system cannot always meet the cooling demand of residents due to the mismatch between solar power and the refrigeration load. Therefore, the thermal energy storage device is introduced into the solar-assisted system to increase the stability of the refrigeration system and reduce the waste of solar energy. In this contribution, a solar-assisted absorption chiller system together with the TES device is presented and optimized to minimize the operation cost of the system. The system is modeled using the newly proposed heat current method and its global constraints are constructed, which largely reduces the number of the constraints comparing to the traditional equation-oriented approach. Optimization results present that the optimized design of the system reduces the total operation cost effectively.
10
Zhang, Tiejun, Juan Catano, Rongliang Zhou, and John T. Wen. "Dynamic Modeling of Refrigeration Cycle for Electronics Cooling." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-69047.
Full textAbstract:
In this paper a refrigeration cycle consisting of multiple evaporators, liquid accumulator, compressor, condenser and expansion valves is analyzed. In the cycle the evaporators and condenser are treated as dynamic components while the liquid accumulator, compressor and the expansion valve are consider static components. For the dynamic components, equations for conservation of mass, energy and momentum are used to characterize the comprehensive transient behaviors. One of the differences with previous models is the use of the momentum equation which is typically neglected in traditional vapor compression refrigeration systems, but it is important in electronics cooling where microchannels are commonly used and a significant pressure drop is observed in the evaporator. This model is expected to have higher accuracy than previously used lumped parameter approximation while maintaining its simplicity to be useful for control purposes. The compressor and expansion valves are modeled using empirical relations, the accumulator is used to guarantee proper operation of the compressor. Local system stability is analyzed using a linearized model at some operating condition and an experimental testbed is developed to validate the model. The test bed consists of three electrically controlled heaters immersed in the refrigeration loop which act as the evaporators. A heated tank as an accumulator for operation at wide range of operating conditions, including low quality at the evaporator outlets. A reciprocating compressor with variable frequency drive to operate at various mass flow rates. The condenser is a flat plate heat exchanger and finally three electronically controlled expansion valves for evaporators.