Chapter 3 Moist Thermodynamics
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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. -
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. -
Guide to Understanding Condensation
Guide to Understanding Condensation The complete Andersen® Owner-To-Owner™ limited warranty is available at: www.andersenwindows.com. “Andersen” is a registered trademark of Andersen Corporation. All other marks where denoted are marks of Andersen Corporation. © 2007 Andersen Corporation. All rights reserved. 7/07 INTRODUCTION 2 The moisture that suddenly appears in cold weather on the interior We have created this brochure to answer questions you may have or exterior of window and patio door glass can block the view, drip about condensation, indoor humidity and exterior condensation. on the floor or freeze on the glass. It can be an annoying problem. We’ll start with the basics and offer solutions and alternatives While it may seem natural to blame the windows or doors, interior along the way. condensation is really an indication of excess humidity in the home. Exterior condensation, on the other hand, is a form of dew — the Should you run into problems or situations not covered in the glass simply provides a surface on which the moisture can condense. following pages, please contact your Andersen retailer. The important thing to realize is that if excessive humidity is Visit the Andersen website: www.andersenwindows.com causing window condensation, it may also be causing problems elsewhere in your home. Here are some other signs of excess The Andersen customer service toll-free number: 1-888-888-7020. humidity: • A “damp feeling” in the home. • Staining or discoloration of interior surfaces. • Mold or mildew on surfaces or a “musty smell.” • Warped wooden surfaces. • Cracking, peeling or blistering interior or exterior paint. -
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. -
Chapter 3 Bose-Einstein Condensation of an Ideal
Chapter 3 Bose-Einstein Condensation of An Ideal Gas An ideal gas consisting of non-interacting Bose particles is a ¯ctitious system since every realistic Bose gas shows some level of particle-particle interaction. Nevertheless, such a mathematical model provides the simplest example for the realization of Bose-Einstein condensation. This simple model, ¯rst studied by A. Einstein [1], correctly describes important basic properties of actual non-ideal (interacting) Bose gas. In particular, such basic concepts as BEC critical temperature Tc (or critical particle density nc), condensate fraction N0=N and the dimensionality issue will be obtained. 3.1 The ideal Bose gas in the canonical and grand canonical ensemble Suppose an ideal gas of non-interacting particles with ¯xed particle number N is trapped in a box with a volume V and at equilibrium temperature T . We assume a particle system somehow establishes an equilibrium temperature in spite of the absence of interaction. Such a system can be characterized by the thermodynamic partition function of canonical ensemble X Z = e¡¯ER ; (3.1) R where R stands for a macroscopic state of the gas and is uniquely speci¯ed by the occupa- tion number ni of each single particle state i: fn0; n1; ¢ ¢ ¢ ¢ ¢ ¢g. ¯ = 1=kBT is a temperature parameter. Then, the total energy of a macroscopic state R is given by only the kinetic energy: X ER = "ini; (3.2) i where "i is the eigen-energy of the single particle state i and the occupation number ni satis¯es the normalization condition X N = ni: (3.3) i 1 The probability -
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 -
Moist Static Energy Budget of MJO-Like Disturbances in The
1 Moist Static Energy Budget of MJO-like 2 disturbances in the atmosphere of a zonally 3 symmetric aquaplanet 4 5 6 Joseph Allan Andersen1 7 Department of Physics, Harvard University, Cambridge, Massachusetts 8 9 10 Zhiming Kuang 11 Department of Earth and Planetary Science and School of Engineering 12 and Applied Sciences, Harvard University, Cambridge, Massachusetts 13 14 15 16 17 18 19 20 21 22 1 Corresponding author address: Joseph Andersen, Department of Physics, Harvard University, Cambridge, MA 02138. E-mail: [email protected] 1 1 2 Abstract 3 A Madden-Julian Oscillation (MJO)-like spectral feature is observed in the time-space 4 spectra of precipitation and column integrated Moist Static Energy (MSE) for a zonally 5 symmetric aquaplanet simulated with Super-Parameterized Community Atmospheric 6 Model (SP-CAM). This disturbance possesses the basic structural and propagation 7 features of the observed MJO. 8 To explore the processes involved in propagation and maintenance of this disturbance, 9 we analyze the MSE budget of the disturbance. We observe that the disturbances 10 propagate both eastwards and polewards. The column integrated long-wave heating is the 11 only significant source of column integrated MSE acting to maintain the MJO-like 12 anomaly balanced against the combination of column integrated horizontal and vertical 13 advection of MSE and Latent Heat Flux. Eastward propagation of the MJO-like 14 disturbance is associated with MSE generated by both column integrated horizontal and 15 vertical advection of MSE, with the column long-wave heating generating MSE that 16 retards the propagation. 17 The contribution to the eastward propagation by the column integrated horizontal 18 advection of MSE is dominated by synoptic eddies. -
It's Just a Phase!
BASIS Lesson Plan Lesson Name: It’s Just a Phase! Grade Level Connection(s) NGSS Standards: Grade 2, Physical Science FOSS CA Edition: Grade 3 Physical Science: Matter and Energy Module *Note to teachers: Detailed standards connections can be found at the end of this lesson plan. Teaser/Overview Properties of matter are illustrated through a series of demonstrations and hands-on explorations. Students will learn to identify solids, liquids, and gases. Water will be used to demonstrate the three phases. Students will learn about sublimation through a fun experiment with dry ice (solid CO2). Next, they will compare the propensity of several liquids to evaporate. Finally, they will learn about freezing and melting while making ice cream. Lesson Objectives ● Students will be able to identify the three states of matter (solid, liquid, gas) based on the relative properties of those states. ● Students will understand how to describe the transition from one phase to another (melting, freezing, evaporation, condensation, sublimation) ● Students will learn that matter can change phase when heat/energy is added or removed Vocabulary Words ● Solid: A phase of matter that is characterized by a resistance to change in shape and volume. ● Liquid: A phase of matter that is characterized by a resistance to change in volume; a liquid takes the shape of its container ● Gas: A phase of matter that can change shape and volume ● Phase change: Transformation from one phase of matter to another ● Melting: Transformation from a solid to a liquid ● Freezing: Transformation -
Capillary Condensation of Colloid–Polymer Mixtures Confined
INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF PHYSICS: CONDENSED MATTER J. Phys.: Condens. Matter 15 (2003) S3411–S3420 PII: S0953-8984(03)66420-9 Capillary condensation of colloid–polymer mixtures confined between parallel plates Matthias Schmidt1,Andrea Fortini and Marjolein Dijkstra Soft Condensed Matter, Debye Institute, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands Received 21 July 2003 Published 20 November 2003 Onlineatstacks.iop.org/JPhysCM/15/S3411 Abstract We investigate the fluid–fluid demixing phase transition of the Asakura–Oosawa model colloid–polymer mixture confined between two smooth parallel hard walls using density functional theory and computer simulations. Comparing fluid density profiles for statepoints away from colloidal gas–liquid coexistence yields good agreement of the theoretical results with simulation data. Theoretical and simulation results predict consistently a shift of the demixing binodal and the critical point towards higher polymer reservoir packing fraction and towards higher colloid fugacities upon decreasing the plate separation distance. This implies capillary condensation of the colloid liquid phase, which should be experimentally observable inside slitlike micropores in contact with abulkcolloidal gas. 1. Introduction Capillary condensation denotes the phenomenon that spatial confinement can stabilize a liquid phase coexisting with its vapour in bulk [1, 2]. In order for this to happen the attractive interaction between the confining walls and the fluid particles needs to be sufficiently strong. Although the main body of work on this subject has been done in the context of confined simple liquids, one might expect that capillary condensation is particularly well suited to be studied with colloidal dispersions. In these complex fluids length scales are on the micron rather than on the ångstrom¨ scale which is typical for atomicsubstances.