Solar Thermal Conversion*
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Thermal Mass
Thermal Mass • What is Thermal Mass? • Types of Thermal Mass • Historical Applications • Thermal Properties of Materials • Analyzing Heat/Cool Storage • Strategies • Other Factors • Computer Analysis • Bibliography Thermal Mass • Thermal mass refers to materials have the capacity to store thermal energy for extended periods. • Thermal mass can be used effectively to absorb daytime heat gains (reducing cooling load) and release the heat during the night (reducing heat load). Types of Thermal Mass • Traditional types of thermal mass include water, rock, earth, brick, concrete, fibrous cement, caliche, and ceramic tile. • Phase change materials store energy while maintaining constant temperatures, using chemical bonds to store & release latent heat. PCM’s include solid-liquid Glauber’s salt, paraffin wax, and the newer solid-solid linear crystalline alkyl hydrocarbons (K-18: 77oF phase transformation temperature). PCM’s can store five to fourteen times more heat per unit volume than traditional materials. (source: US Department of Energy). Historical Applications • The use of thermal mass in shelter dates back to the dawn of humans, and until recently has been the prevailing strategy for building climate control in hot regions. Egyptian mud-brick storage rooms (3200 years old). The lime-pozzolana (concrete) Roman Pantheon Today, passive techniques such as thermal mass are ironically considered “alternative” methods to mechanical heating and cooling, yet the appropriate use of thermal mass offers an efficient integration of structure and thermal services. Thermal Properties of Materials The basic properties that indicate the thermal behavior of materials are: density (p), specific heat (cm), and conductivity (k). The specific heat for most masonry materials is similar (about 0.2-0.25Wh/kgC). -
Thermodynamics of Solar Energy Conversion in to Work
Sri Lanka Journal of Physics, Vol. 9 (2008) 47-60 Institute of Physics - Sri Lanka Research Article Thermodynamic investigation of solar energy conversion into work W.T.T. Dayanga and K.A.I.L.W. Gamalath Department of Physics, University of Colombo, Colombo 03, Sri Lanka Abstract Using a simple thermodynamic upper bound efficiency model for the conversion of solar energy into work, the best material for a converter was obtained. Modifying the existing detailed terrestrial application model of direct solar radiation to include an atmospheric transmission coefficient with cloud factors and a maximum concentration ratio, the best shape for a solar concentrator was derived. Using a Carnot engine in detailed space application model, the best shape for the mirror of a concentrator was obtained. A new conversion model was introduced for a solar chimney power plant to obtain the efficiency of the power plant and power output. 1. INTRODUCTION A system that collects and converts solar energy in to mechanical or electrical power is important from various aspects. There are two major types of solar power systems at present, one using photovoltaic cells for direct conversion of solar radiation energy in to electrical energy in combination with electrochemical storage and the other based on thermodynamic cycles. The efficiency of a solar thermal power plant is significantly higher [1] compared to the maximum efficiency of twenty percent of a solar cell. Although the initial cost of a solar thermal power plant is very high, the running cost is lower compared to the other power plants. Therefore most countries tend to build solar thermal power plants. -
Criteria and Guidelines for Product and System Developers
D E S I G N I N G S O L A R T H E R M A L S Y S T E M S F O R A R C H I T E C T U R A L I N T E G R A T I O N criteria and guidelines for product and system developers T.41.A.3/1 Task 41 ‐ Solar energy & Architecture ‐ International Energy Agency ‐ Solar Heating and Cooling Programme Report T.41.A.3/1: IEA SHC Task 41 Solar Energy and Architecture DESIGNING SOLAR THERMAL SYSTEMS FOR ARCHITECTURAL INTEGRATION Criteria and guidelines for product and system developers Keywords Solar energy, architectural integration, solar thermal, active solar systems, solar buildings, solar architecture, solar products, innovative products, building integrability. Editors: MariaCristina Munari Probst Christian Roecker November 2013 T.41.A.3/1 IEA SHC Task 41 I Designing solar thermal systems for architectural integration AUTHORS AND CONTRIBUTORS AFFILIATIONS Maria Cristina Munari Probst Christian Roecker (editor, author) (editor, author) EPFL‐LESO EPFL‐LESO Bâtiment LE Bâtiment LE Station 18 Station 18 CH‐1015 Lausanne CH‐1015 Lausanne SWITZERLAND SWITZERLAND [email protected] [email protected] Alessia Giovanardi Marja Lundgren Maria Wall - Operating agent (contributor) (contributor) (contributor) EURAC research, Institute for White Arkitekter Energy and Building Design Renewable Energy P.O. Box 4700 Lund University Universitá degli Studi di Trento Östgötagatan 100 P.O. Box 118 Viale Druso 1 SE‐116 92 Stockholm SE‐221 00 Lund SWEDEN I‐39100 Bolzano, ITALY SWEDEN [email protected] [email protected] [email protected] 1 T.41.A.3/1 IEA SHC Task 41 I Designing solar thermal systems for architectural integration 2 T.41.A.3/1 IEA SHC Task 41 I Designing solar thermal systems for architectural integration ACKNOWLEDGMENTS The authors are grateful to the International Energy Agency for understanding the importance of this subject and accepting to initiate a Task on solar energy and architecture. -
Solar Thermal Energy
22 Solar Thermal Energy Solar thermal energy is an application of solar energy that is very different from photovol- taics. In contrast to photovoltaics, where we used electrodynamics and solid state physics for explaining the underlying principles, solar thermal energy is mainly based on the laws of thermodynamics. In this chapter we give a brief introduction to that field. After intro- ducing some basics in Section 22.1, we will discuss Solar Thermal Heating in Section 22.2 and Concentrated Solar (electric) Power (CSP) in Section 22.3. 22.1 Solar thermal basics We start this section with the definition of heat, which sometimes also is called thermal energy . The molecules of a body with a temperature different from 0 K exhibit a disordered movement. The kinetic energy of this movement is called heat. The average of this kinetic energy is related linearly to the temperature of the body. 1 Usually, we denote heat with the symbol Q. As it is a form of energy, its unit is Joule (J). If two bodies with different temperatures are brought together, heat will flow from the hotter to the cooler body and as a result the cooler body will be heated. Dependent on its physical properties and temperature, this heat can be absorbed in the cooler body in two forms, sensible heat and latent heat. Sensible heat is that form of heat that results in changes in temperature. It is given as − Q = mC p(T2 T1), (22.1) where Q is the amount of heat that is absorbed by the body, m is its mass, Cp is its heat − capacity and (T2 T1) is the temperature difference. -
Empirical Modelling of Einstein Absorption Refrigeration System
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 75, Issue 3 (2020) 54-62 Journal of Advanced Research in Fluid Mechanics and Thermal Sciences Journal homepage: www.akademiabaru.com/arfmts.html ISSN: 2289-7879 Empirical Modelling of Einstein Absorption Refrigeration Open Access System Keng Wai Chan1,*, Yi Leang Lim1 1 School of Mechanical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia ARTICLE INFO ABSTRACT Article history: A single pressure absorption refrigeration system was invented by Albert Einstein and Received 4 April 2020 Leo Szilard nearly ninety-year-old. The system is attractive as it has no mechanical Received in revised form 27 July 2020 moving parts and can be driven by heat alone. However, the related literature and Accepted 5 August 2020 work done on this refrigeration system is scarce. Previous researchers analysed the Available online 20 September 2020 refrigeration system theoretically, both the system pressure and component temperatures were fixed merely by assumption of ideal condition. These values somehow have never been verified by experimental result. In this paper, empirical models were proposed and developed to estimate the system pressure, the generator temperature and the partial pressure of butane in the evaporator. These values are important to predict the system operation and the evaporator temperature. The empirical models were verified by experimental results of five experimental settings where the power input to generator and bubble pump were varied. The error for the estimation of the system pressure, generator temperature and partial pressure of butane in evaporator are ranged 0.89-6.76%, 0.23-2.68% and 0.28-2.30%, respectively. -
Teaching Psychrometry to Undergraduates
AC 2007-195: TEACHING PSYCHROMETRY TO UNDERGRADUATES Michael Maixner, U.S. Air Force Academy James Baughn, University of California-Davis Michael Rex Maixner graduated with distinction from the U. S. Naval Academy, and served as a commissioned officer in the USN for 25 years; his first 12 years were spent as a shipboard officer, while his remaining service was spent strictly in engineering assignments. He received his Ocean Engineer and SMME degrees from MIT, and his Ph.D. in mechanical engineering from the Naval Postgraduate School. He served as an Instructor at the Naval Postgraduate School and as a Professor of Engineering at Maine Maritime Academy; he is currently a member of the Department of Engineering Mechanics at the U.S. Air Force Academy. James W. Baughn is a graduate of the University of California, Berkeley (B.S.) and of Stanford University (M.S. and PhD) in Mechanical Engineering. He spent eight years in the Aerospace Industry and served as a faculty member at the University of California, Davis from 1973 until his retirement in 2006. He is a Fellow of the American Society of Mechanical Engineering, a recipient of the UCDavis Academic Senate Distinguished Teaching Award and the author of numerous publications. He recently completed an assignment to the USAF Academy in Colorado Springs as the Distinguished Visiting Professor of Aeronautics for the 2004-2005 and 2005-2006 academic years. Page 12.1369.1 Page © American Society for Engineering Education, 2007 Teaching Psychrometry to Undergraduates by Michael R. Maixner United States Air Force Academy and James W. Baughn University of California at Davis Abstract A mutli-faceted approach (lecture, spreadsheet and laboratory) used to teach introductory psychrometric concepts and processes is reviewed. -
Thermodynamics of Interacting Magnetic Nanoparticles
This is a repository copy of Thermodynamics of interacting magnetic nanoparticles. White Rose Research Online URL for this paper: https://eprints.whiterose.ac.uk/168248/ Version: Accepted Version Article: Torche, P., Munoz-Menendez, C., Serantes, D. et al. (6 more authors) (2020) Thermodynamics of interacting magnetic nanoparticles. Physical Review B. 224429. ISSN 2469-9969 https://doi.org/10.1103/PhysRevB.101.224429 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ Thermodynamics of interacting magnetic nanoparticles P. Torche1, C. Munoz-Menendez2, D. Serantes2, D. Baldomir2, K. L. Livesey3, O. Chubykalo-Fesenko4, S. Ruta5, R. Chantrell5, and O. Hovorka1∗ 1School of Engineering and Physical Sciences, University of Southampton, Southampton SO16 7QF, UK 2Instituto de Investigaci´ons Tecnol´oxicas and Departamento de F´ısica Aplicada, Universidade de Santiago de Compostela, -
Understanding Psychrometrics, Third Edition It’S Really a Mine of Information
Gatley The Comprehensive Guide to Psychrometrics Understanding Psychrometrics serves as a lifetime reference manual and basic refresher course for those who use psychrometrics on a recurring basis and provides a four- to six-hour psychrometrics learning module to students; air- conditioning designers; agricultural, food process, and industrial process engineers; Understanding Psychrometrics meteorologists and others. Understanding Psychrometrics Third Edition New in the Third Edition • Revised chapters for wet-bulb temperature and relative humidity and a revised Appendix V that includes a summary of ASHRAE Research Project RP-1485. • New constants for the universal gas constant based on CODATA and a revised molar mass of dry air to account for the increase of CO2 in Earth’s atmosphere. • New IAPWS models for the calculation of water properties above and below freezing. • New tables based on the ASHRAE RP-1485 real moist-air numerical model using the ASHRAE LibHuAirProp add-ins for Excel®, MATLAB®, Mathcad®, and EES®. Includes Access to Bonus Materials and Sample Software • PDF files of 13 ultra-high-pressure and 12 existing ASHRAE psychrometric charts plus three new 0ºC to 400ºC charts. • A limited demonstration version of the ASHRAE LibHuAirProp add-in that allows users to duplicate portions of the real moist-air psychrometric tables in the ASHRAE Handbook—Fundamentals for both standard sea level atmospheric pressure and pressures from 5 to 10,000 kPa. • The hw.exe program from the second edition, included to enable users to compare the 2009 ASHRAE numerical model real moist-air psychrometric properties with the 1983 ASHRAE-Hyland-Wexler properties. Praise for Understanding Psychrometrics, Third Edition It’s really a mine of information. -
Quantized Refrigerator for an Atomic Cloud
Quantized refrigerator for an atomic cloud Wolfgang Niedenzu1, Igor Mazets2,3, Gershon Kurizki4, and Fred Jendrzejewski5 1Institut für Theoretische Physik, Universität Innsbruck, Technikerstraße 21a, A-6020 Innsbruck, Austria 2Vienna Center for Quantum Science and Technology (VCQ), Atominstitut, TU Wien, 1020 Vienna, Austria 3Wolfgang Pauli Institute, c/o Fakultät für Mathematik, Universität Wien, 1090 Vienna, Austria 4Department of Chemical Physics, Weizmann Institute of Science, Rehovot 7610001, Israel 5Heidelberg University, Kirchhoff-Institut für Physik, Im Neuenheimer Feld 227, D-69120 Heidelberg, Germany June 24, 2019 We propose to implement a quantized ther- a) mal machine based on a mixture of two atomic species. One atomic species implements the working medium and the other implements two (cold and hot) baths. We show that such a setup can be employed for the refrigeration of a large bosonic cloud starting above and end- ing below the condensation threshold. We ana- lyze its operation in a regime conforming to the b) quantized Otto cycle and discuss the prospects for continuous-cycle operation, addressing the experimental as well as theoretical limitations. <latexit sha1_base64="xPORfqE4jiv0WYJsIrI5dlUB7fE=">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</latexit>Beyond -
The Wind-Catcher, a Traditional Solution for a Modern Problem Narguess
THE WIND-CATCHER, A TRADITIONAL SOLUTION FOR A MODERN PROBLEM NARGUESS KHATAMI A submission presented in partial fulfilment of the requirements of the University of Glamorgan/ Prifysgol Morgannwg for the degree of Master of Philosophy August 2009 I R11 1 Certificate of Research This is to certify that, except where specific reference is made, the work described in this thesis is the result of the candidate’s research. Neither this thesis, nor any part of it, has been presented, or is currently submitted, in candidature for any degree at any other University. Signed ……………………………………… Candidate 11/10/2009 Date …………………………………....... Signed ……………………………………… Director of Studies 11/10/2009 Date ……………………………………… II Abstract This study investigated the ability of wind-catcher as an environmentally friendly component to provide natural ventilation for indoor environments and intended to improve the overall efficiency of the existing designs of modern wind-catchers. In fact this thesis attempts to answer this question as to if it is possible to apply traditional design of wind-catchers to enhance the design of modern wind-catchers. Wind-catchers are vertical towers which are installed above buildings to catch and introduce fresh and cool air into the indoor environment and exhaust inside polluted and hot air to the outside. In order to improve overall efficacy of contemporary wind-catchers the study focuses on the effects of applying vertical louvres, which have been used in traditional systems, and horizontal louvres, which are applied in contemporary wind-catchers. The aims are therefore to compare the performance of these two types of louvres in the system. For this reason, a Computational Fluid Dynamic (CFD) model was chosen to simulate and study the air movement in and around a wind-catcher when using vertical and horizontal louvres. -
Thermodynamics the Study of the Transformations of Energy from One Form Into Another
Thermodynamics the study of the transformations of energy from one form into another First Law: Heat and Work are both forms of Energy. in any process, Energy can be changed from one form to another (including heat and work), but it is never created or distroyed: Conservation of Energy Second Law: Entropy is a measure of disorder; Entropy of an isolated system Increases in any spontaneous process. OR This law also predicts that the entropy of an isolated system always increases with time. Third Law: The entropy of a perfect crystal approaches zero as temperature approaches absolute zero. ©2010, 2008, 2005, 2002 by P. W. Atkins and L. L. Jones ©2010, 2008, 2005, 2002 by P. W. Atkins and L. L. Jones A Molecular Interlude: Internal Energy, U, from translation, rotation, vibration •Utranslation = 3/2 × nRT •Urotation = nRT (for linear molecules) or •Urotation = 3/2 × nRT (for nonlinear molecules) •At room temperature, the vibrational contribution is small (it is of course zero for monatomic gas at any temperature). At some high temperature, it is (3N-5)nR for linear and (3N-6)nR for nolinear molecules (N = number of atoms in the molecule. Enthalpy H = U + PV Enthalpy is a state function and at constant pressure: ∆H = ∆U + P∆V and ∆H = q At constant pressure, the change in enthalpy is equal to the heat released or absorbed by the system. Exothermic: ∆H < 0 Endothermic: ∆H > 0 Thermoneutral: ∆H = 0 Enthalpy of Physical Changes For phase transfers at constant pressure Vaporization: ∆Hvap = Hvapor – Hliquid Melting (fusion): ∆Hfus = Hliquid – -
Ecology Design
ECOLOGY and DESIGN Ecological Literacy in Architecture Education 2006 Report and Proposal The AIA Committee on the Environment Cover photos (clockwise) Cornell University's entry in the 2005 Solar Decathlon included an edible garden. This team earned second place overall in the competition. Photo by Stefano Paltera/Solar Decathlon Students collaborating in John Quale's ecoMOD course (University of Virginia), which received special recognition in this report (see page 61). Photo by ecoMOD Students in Jim Wasley's Green Design Studio and Professional Practice Seminar (University of Wisconsin-Milwaukee) prepare to present to their client; this course was one of the three Ecological Literacy in Architecture Education grant recipients (see page 50). Photo by Jim Wasley ECOLOGY and DESIGN Ecological by Kira Gould, Assoc. AIA Literacy in Lance Hosey, AIA, LEED AP Architecture with contributions by Kathleen Bakewell, LEED AP Education Kate Bojsza, Assoc. AIA 2006 Report Peter Hind , Assoc. AIA Greg Mella, AIA, LEED AP and Proposal Matthew Wolf for the Tides Foundation Kendeda Sustainability Fund The contents of this report represent the views and opinions of the authors and do not necessarily represent the opinions of the American Institute of Architects (AIA). The AIA supports the research efforts of the AIA’s Committee on the Environment (COTE) and understands that the contents of this report may reflect the views of the leadership of AIA COTE, but the views are not necessarily those of the staff and/or managers of the Institute. The AIA Committee