The Portion of the Universe Under Study Surroundings

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Thermodynamics: a few definitions system: the portion of the universe under study surroundings: the rest of the universe boundary: separates the system from the surroundings closed system: matter cannot enter or leave (impermeable boundary) heat may enter or leave; work may be done open system: matter may enter or leave (permeable boundary) isolated system: boundary prevents any interaction with the system no heat or matter may enter or leave no work may be done by the system on the surroundings or by the surroundings on the system rigid, impermeable, adiabatic wall adiabatic system: no heat exchange between the system and the surroundings the boundary is an adiabatic wall an adiabatic system is a perfectly insulated system state: the state of a system is defined by specifying its properties properties with numerical values can be divided into two categories: intensive properties: magnitude does not depend upon the amount of substance temperature, pressure, concentration, density, molar volume extensive properties: magnitude depends on the amount of substance total value equals the sum of its values for all parts of the system volume, mass, change in enthalpy homogeneous system: intensive properties constant throughout (opposite: heterogeneous) a phase is a homogeneous part of a system A state variable (also called a state function, thermodynamic variable, thermodynamic function) depends only on the state of the system. state of equilibrium: (a) system shows no further tendency to change its properties with time (b) removal from contact with surroundings causes no further change in properties if (a) but not (b), system is in a steady state) can specify an equilibrium state by its state functions; in fact, only a few are needed (not as easy to specify a nonequilibrium state) one can further subdivide the concept of equilibrium: 1. mechanical equilibrium: no unbalanced forces acting on or within the system (a system in mechanical equilibrium has a well-defined pressure) 2. material equilibrium: no net chemical reaction no net transfer of matter from one part of the system to another 3. thermal equilibrium: a system and its surroundings are in thermal equilibrium if there are no changes in the properties of the system when the system and surroundings are separated by a thermally conducting wall .

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Guggenheim Aeronautical Laboratory~://; California
R.ES~.LttCH REPCRT GUGGENHEIM AERONAUTICAL LABORATORY ~://; CALIFORNIA INSTITUTE OF TECHNOLOGY HYPERSC»JIC RESEARCH PROJECT Memorandum No. 47 December 15, 1958 AN EXPERIMENTAL INVESTIGATION OF THE EFFECT OF EJECTING A COOLANT GAS AT THE NOSE OF A BLUNT BODY by C. Hugh E. Warren ARMY ORDNANCE CONTRACT NO. DA-04-495-0rd-19 GUGGENHEIM AERONAUTICAL LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena1 California HYPERSONIC RESEARCH PROJECT Memorandum No. 4 7 December 151 1958 AN EXPERIMENTAL INVESTIGATION OF THE EFFECT OF EJECTING A COOLANT GAS AT THE NOSE OF A BLUNT BODY by C. Hugh E. Warren ~~C!a r~:Ml ia:nl bil'eCtOr Guggenheim Aeronautical Laboratory ARMY ORDNANCE CONTRACT NO. DA-04-495-0rd-19 Army Project No. 5B0306004 Ordnance Project No. TB3-0118 OOR Project No. 1600-PE ACKNOWLEDGMENTS The author wishes to express his appreciation to Professor Lester Lees for his assistance1 guidance and encouragement during this work1 to Mr. Howard McDonald and other members of the Aeronautics Machine Shop for fabricating and maintaining the models and other items of equipment1 to Mr. Paul Baloga and the staff of the Hypersonic Wind Tunnel for their assistance and advice during testing~ to Mrs. Betty Laue for much computational work1 and to Mrs. Gerry Van Gieson for typing the manuscript and piloting the report through after the author 1 s departure. Most of the work was done while the author was in receipt of a Harkness Fellowship of the Commonwealth Fund of New York1 to whom thanks are due for the opportunity to spend a year on such an instructive and interesting program in such congenial surroundings.
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Application of Laser Doppler Velocimetry
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Conduction Heat Transfer Notes for MECH 7210
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Thermodynamic Processes: the Limits of Possible
Thermodynamic Processes: The Limits of Possible Thermodynamics put severe restrictions on what processes involving a change of the thermodynamic state of a system (U,V,N,…) are possible. In a quasi-static process system moves from one equilibrium state to another via a series of other equilibrium states . All quasi-static processes fall into two main classes: reversible and irreversible processes . Processes with decreasing total entropy of a thermodynamic system and its environment are prohibited by Postulate II Notes Graphic representation of a single thermodynamic system Phase space of extensive coordinates The fundamental relation S(1) =S(U (1) , X (1) ) of a thermodynamic system defines a hypersurface in the coordinate space S(1) S(1) U(1) U(1) X(1) X(1) S(1) – entropy of system 1 (1) (1) (1) (1) (1) U – energy of system 1 X = V , N 1 , …N m – coordinates of system 1 Notes Graphic representation of a composite thermodynamic system Phase space of extensive coordinates The fundamental relation of a composite thermodynamic system S = S (1) (U (1 ), X (1) ) + S (2) (U-U(1) ,X (2) ) (system 1 and system 2). defines a hyper-surface in the coordinate space of the composite system S(1+2) S(1+2) U (1,2) X = V, N 1, …N m – coordinates U of subsystems (1 and 2) X(1,2) (1,2) S – entropy of a composite system X U – energy of a composite system Notes Irreversible and reversible processes If we change constraints on some of the composite system coordinates, (e.g.
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Heat Transfer in Nanofluid Boundary Layer Near Adiabatic Wall
Copyright © 2018 by American Scientific Publishers Journal of Nanofluids All rights reserved. Vol. 7, pp. 1297–1302, 2018 Printed in the United States of America (www.aspbs.com/jon) Heat Transfer in Nanofluid Boundary Layer Near Adiabatic Wall D. Hopper, D. Jaganathan, J. L. Orr, J. Shi, F. Simeski, M. Yin, and J. T. C. Liu∗ School of Engineering (ENGN 2760) and Fluids@Brown, Brown University, Providence, Rhode Island 02912, USA Heat transfer in nanofluid boundary layers has been receiving significant attention in recent years due to widespread applications and ongoing research in both academia and industry. Cooling systems in batteries, semiconductors, and other components in the hardware technology industry are just a few areas where the limits of heat transfer are being pushed. The principal region of heat exchange between the wall and fluid is within the thermal boundary layer. Intriguingly, the heat transfer of particle-laden nanofluid is greatly affected by both the appearance of the particle and the nanoscale molecular effects; hence, a thorough characterization of the boundary layer behaviour and properties is needed. Prior research has shown that nanofluids enhance the heat transfer. Based on related works (J. T. C. Liu, Proc. Royal Society A 408, 2383 (2012); J. T. C. Liu, et al., Arch. Mech. 69, 75 (2017); C. J. B. de Castilho, et al., J. Heat Transfer Eng. 1 (2018)), convective heat transfer in nanofluid boundary layers is studied by a theoretical model with first-order perturbation of variables. Small nanoparticle volume concentration is assumed. A theoretical model of nanofluid flow over an adiabatic wall is ARTICLE presented, and the corresponding temperature and velocity profiles are obtained.
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Thermodynamics
CHAPTER TWELVE THERMODYNAMICS 12.1 INTRODUCTION In previous chapter we have studied thermal properties of matter. In this chapter we shall study laws that govern thermal energy. We shall study the processes where work is 12.1 Introduction converted into heat and vice versa. In winter, when we rub 12.2 Thermal equilibrium our palms together, we feel warmer; here work done in rubbing 12.3 Zeroth law of produces the ‘heat’. Conversely, in a steam engine, the ‘heat’ Thermodynamics of the steam is used to do useful work in moving the pistons, 12.4 Heat, internal energy and which in turn rotate the wheels of the train. work In physics, we need to define the notions of heat, 12.5 First law of temperature, work, etc. more carefully. Historically, it took a thermodynamics long time to arrive at the proper concept of ‘heat’. Before the 12.6 Specific heat capacity modern picture, heat was regarded as a fine invisible fluid 12.7 Thermodynamic state filling in the pores of a substance. On contact between a hot variables and equation of body and a cold body, the fluid (called caloric) flowed from state the colder to the hotter body! This is similar to what happens 12.8 Thermodynamic processes when a horizontal pipe connects two tanks containing water 12.9 Heat engines up to different heights. The flow continues until the levels of 12.10 Refrigerators and heat water in the two tanks are the same. Likewise, in the ‘caloric’ pumps picture of heat, heat flows until the ‘caloric levels’ (i.e., the 12.11 Second law of temperatures) equalise.
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MODI Fled CROCCO- LEES M Lxi NG THEORY for SUPERSONIC SEPARATED and REATTACHING FLOWS by Herbert S
RESEARCH REPORT ·~yl GUGGENHEIM AERONAUTICAL LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY ~ HYPERSONIC RESEARCH PROJECT Memorandum No. 53 May 2, 1960 MODI FlED CROCCO- LEES M lXI NG THEORY FOR SUPERSONIC SEPARATED AND REATTACHING FLOWS by Herbert S . Glick AUG - 3 1960 ARMY ORDNANCE CONTRACT NO. DA-04-495-0rd-1960 - GUGGENHEIM AERONAUTICAL LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California HYPERSONIC RESEARCH PROJECT ERRATA FOR 1962 Memorandwn No. 53 .f~o ~ May 2, 1960 ~ £NGNG. SCI. t\Y.~~ "Modified Crocco-Lees Mixing Theory for Supersonic Separated and Reattaching Flows" by Herbert S. Glick page 74 -- line 12 -- (nwnerator) in the equation L = (denom1nator) the numerator of the equation should read: GUGGENHEIM AERONAUTICAL LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY Pa eadena, California HYPERSONIC RESEARCH PROJECT Memorandum No. 53 May Z, 1960 MODIFIED CROCCO-LEES MIXING THEORY FOR SUPERSONIC SEPARATED AND REATTACHING FLOWS by Herbert S. Glick C~ ar 1 • n uector ARMY ORDNANCE CONTRACT NO. DA-04-495-0rd-1960 ACKNOWLEDGMENTS The author wishes to express his appreciation to Professor Lester Lees for his guidance throughout the course of the investigation. He also wishes to thank Mrs. Betty Laue for her enthusiastic and able assistance in carrying out most of the desk computations; Mrs. Truus van Harreveld, Miss Georgette A. Pauwels, and Mr. Andy Chapkis who assisted in the early computations; Mrs. Betty Wood for preparing the figures, and Mrs. Geraldine VanGieson for her typing of the manu script. The author acknowledges with gratitude the receipt of a sabbatical leave grant from the Cornell Aeronautical Laboratory, Inc. of Buffalo, New York for the year 1957-1958, and a fellowship from the Curtiss Wright Corporation for the year 1958-1959.
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The Foundations of Classical Thermodynamics
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Section 1 Introduction to Classical Thermodynamics
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Investigation of Thermal Adiabatic Boundary Condition on Semitransparent Wall in Combined Radiation and Natural Convection
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