Thermal Systems Design MARYLAND. Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects
|
|
- Shannon Quinn
- 6 years ago
- Views:
Transcription
1 Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects Internal power generation Environmental temperatures Conduction Thermal system components 2002 David L. Akin - All rights reserved
2 Classical Methods of Heat Transfer Convection Heat transferred to cooler surrounding gas, which creates currents to remove hot gas and supply new cool gas Don t (in general) have surrounding gas or gravity for convective currents Conduction Direct heat transfer between touching components Primary heat flow mechanism internal to vehicle Radiation Heat transferred by infrared radiation Only mechanism for dumping heat external to vehicle
3 Ideal Radiative Heat Transfer Planck s equation gives energy emitted in a specific frequency by a black body as a function of temperature e λb = Stefan-Boltzmann equation integrates Planck s equation over entire spectrum Prad = σt 4 W σ = 567. x m K 2 2πhC0 hc λ exp λkt (Don t worry, we won t actually use this equation for anything ) ( Stefan-Boltzmann Constant )
4 Thermodynamic Equilibrium First Law of Thermodynamics Q W = du dt heat in -heat out = work done internally Heat in = incident energy absorbed Heat out = radiated energy Work done internally = internal power used (negative work in this sense - adds to total heat in the system)
5 Radiative Equilibrium Temperature Assume a spherical black body of radius r Heat in due to intercepted solar flux Q = I π r 2 in s Heat out due to radiation (from total surface area) Qout = 4πr σt 2 4 For equilibrium, set equal I πr = 4πr σt I = 4σT s s 1 AU: I s =1394 W/m 2 ; T eq =280 K T eq Is = 4σ 1 4
6 Effect of Distance on Equilibrium Temp Black Body Equilibrium Temperature ( K) Distance from Sun (AU)
7 Shape and Radiative Equilibrium A shape absorbs energy only via illuminated faces A shape radiates energy via all surface area Basic assumption made is that black bodies are intrinsically isothermal (perfect and instantaneous conduction of heat internally to all faces)
8 Effect of Shape on Black Body Temps Black Body Equilibrium Temperature ( K) Spherical Black Body Adiabatic Black Wall Double-Sided Wall Distance from Sun (AU)
9 Incident Radiation on Non-Ideal Bodies Kirchkoff s Law for total incident energy flux on solid bodies: QIncident = Qabsorbed + Qreflected + Qtransmitted Q Q Q absorbed reflected transmitted + + =1 QIncident QIncident QIncident Q Q absorbed reflected α ; ρ ; τ Q Q where Incident α =absorptance (or absorptivity) ρ =reflectance (or reflectivity) τ =transmittance (or transmissivity) Incident Q Q transmitted Incident
10 Non-Ideal Radiative Equilibrium Temp Assume a spherical black body of radius r Heat in due to intercepted solar flux Q = Iαπ r 2 in s Heat out due to radiation (from total surface area) Qout = 4πr εσt 2 4 For equilibrium, set equal (ε = emissivity - efficiency of surface at radiating heat) ε Isαπ r = 4π r εσt Is = 4 T α σ T eq Is = α ε 4σ 1 4
11 Effect of Surface Coating on Temperature Black Ni, Cr, Cu Black Paint Aluminum Paint Teq=560 K (a/e=4) Teq=471 K (a/e=2) Teq=396 K (a/e=1) Teq=333 K (a/e=0.5) Teq=280 K (a/e=0.25) 0.2 Polished Metals White Paint Optical Surface Reflector
12 Non-Ideal Radiative Heat Transfer Full form of the Stefan-Boltzmann equation P = εσa T T rad ( 4 4 ) env where T env =environmental temperature (=4 K for space) Also take into account power used internally ( ) IαA + P = εσa T T 4 4 s s int rad env
13 Example: AERCam/SPRINT 30 cm diameter sphere α=0.2; ε=0.8 P int =200W T env =280 K (cargo bay below; Earth above) Analysis cases: Free space w/o sun Free space w/sun Earth orbit w/o sun Earth orbit w/sun
14 AERCam/SPRINT Analysis (Free Space) A s = m 2 ; A rad = m 2 Free space, no sun 4 200W Pint = εσaradt T = 8 W m 2 4 m K ( 2) 1 4 = 354 K
15 AERCam/SPRINT Analysis (Free Space) A s = m 2 ; A rad = m 2 Free space with sun 4 IαA + P = εσa T T = s s int rad Isα As+ P εσa rad int 1 4 = 362 K
16 AERCam/SPRINT Analysis (LEO Cargo Bay) T env =280 K LEO cargo bay, no sun 4 4 W Pint = Arad ( T Tenv) T = 200 εσ W m 2 4 m K LEO cargo bay with sun ( ) + 2 Isα As+ P IsαAs + P = εσa ( int rad T Tenv) T = εσa 4 4 int 4 env rad ( 280 K) = 384 K T 1 4 = 391 K
17 Radiative Insulation I s T insulation T wall Thin sheet (mylar/kapton with surface coatings) used to isolate panel from solar flux Panel reaches equilibrium with radiation from sheet and from itself reflected from sheet Sheet reaches equilibrium with radiation from sun and panel, and from itself reflected off panel
18 Multi-Layer Insulation (MLI) I s Multiple insulation layers to cut down on radiative transfer Gets computationally intensive quickly Highly effective means of insulation Biggest problem is existence of conductive leak paths (physical connections to insulated components)
19 1D Conduction Basic law of one-dimensional heat conduction (Fourier 1822) where K=thermal conductivity (W/m K) A=area Q = KA dt dx dt/dx=thermal gradient
20 3D Conduction General differential equation for heat flow in a solid r r r grt (,) ρc Trt, 2 Trt (, )+ = K K t where g(r,t)=internally generated heat ρ=density (kg/m 3 ) c=specific heat (J/kg K) K/ρc=thermal diffusivity ( )
21 Simple Analytical Conduction Model Heat flowing from (i-1) into (i) T i-1 T i T i+1 Q KA T T i in = x i 1 Heat flowing from (i) into (i+1) Q KA T T i+1 out = x Heat remaining in cell Q out Q = in i ρ c Ti( j+ 1) Ti( j) K t
22 Heat Pipe Schematic
23 Shuttle Thermal Control Components
24 Shuttle Thermal Control System Schematic
25 ISS Radiator Assembly
MARYLAND. Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects. Conduction Thermal system components
Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects Internal power generation Environmental temperatures Conduction Thermal system components 2003 David L. Akin - All
More informationThermal Systems Design MARYLAND. Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects
Thermal Systems Design Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects Internal power generation Environmental temperatures Conduction Thermal system components
More informationThermal Systems Design
Thermal Systems Design Fundamentals of heat transfer Radiative equilibrium Surface properties Non-ideal effects Internal power generation Environmental temperatures Conduction Thermal system components
More informationChapter 3 Energy Balance and Temperature. Topics to be covered
Chapter 3 Energy Balance and Temperature Astro 9601 1 Topics to be covered Energy Balance and Temperature (3.1) - All Conduction (3..1), Radiation (3.. and31) 3...1) Convection (3..3), Hydrostatic Equilibrium
More informationChapter 3 Energy Balance and Temperature. Astro 9601
Chapter 3 Energy Balance and Temperature Astro 9601 1 Topics to be covered Energy Balance and Temperature (3.1) - All Conduction (3..1), Radiation (3.. and 3...1) Convection (3..3), Hydrostatic Equilibrium
More informationThermal Radiation Heat Transfer Mechanisms
18-6 Heat Transfer Mechanisms Thermal Radiation Radiation is an energy transfer via the emission of electromagnetic energy. The rate P rad at which an object emits energy via thermal radiation is Here
More informationChapter 10: Steady Heat Conduction
Chapter 0: Steady Heat Conduction In thermodynamics, we considered the amount of heat transfer as a system undergoes a process from one equilibrium state to another hermodynamics gives no indication of
More information2. Illustration of Atmospheric Greenhouse Effect with Simple Models
2. Illustration of Atmospheric Greenhouse Effect with Simple Models In the first lecture, I introduced the concept of global energy balance and talked about the greenhouse effect. Today we will address
More informationRadiative Equilibrium Models. Solar radiation reflected by the earth back to space. Solar radiation absorbed by the earth
I. The arth as a Whole (Atmosphere and Surface Treated as One Layer) Longwave infrared (LWIR) radiation earth to space by the earth back to space Incoming solar radiation Top of the Solar radiation absorbed
More informationMechanisms of heat transfer
Lecture 4 Mechanisms of heat transfer Pre-reading: 17.7 Review Heat can be transferred from one object to another due to a temperature difference. The properties of many objects change with temperature:
More informationTRANSMISSION OF HEAT
TRANSMISSION OF HEAT Synopsis :. In general heat travels from one point to another whenever there is a difference of temperatures.. Heat flows from a body at higher temperature to a lower temperature..
More informationHeat Transfer: Physical Origins and Rate Equations. Chapter One Sections 1.1 and 1.2
Heat Transfer: Physical Origins and Rate Equations Chapter One Sections 1.1 and 1. Heat Transfer and Thermal Energy What is heat transfer? Heat transfer is thermal energy in transit due to a temperature
More informationTHERMODYNAMICS METHODS OF HEAT TRANSFER RADIATION
VISUAL PHYSICS ONLINE THERMODYNAMICS METHODS OF HEAT TRANSFER RADIATION Radiation is the energy transferred by electromagnetic waves mainly infrared (IR), visible and ultraviolet (UV). All materials radiate
More informationHeriot-Watt University
Heriot-Watt University Distinctly Global www.hw.ac.uk Thermodynamics By Peter Cumber Prerequisites Interest in thermodynamics Some ability in calculus (multiple integrals) Good understanding of conduction
More informationRadiation Heat Transfer. Introduction. Blackbody Radiation. Definitions ,
Radiation Heat Transfer Reading Problems 5-5-7 5-27, 5-33, 5-50, 5-57, 5-77, 5-79, 5-96, 5-07, 5-08 Introduction A narrower band inside the thermal radiation spectrum is denoted as the visible spectrum,
More informationThermal Radiation: The Stefan-Boltzmann Law
Thermal Radiation: The Stefan-Boltzmann Law Andy Chmilenko, 20310799 Instructor: Tan Dinh Section 1 (Dated: 2:30 pm Wednesday June 26, 2013) I. PURPOSE The purpose of this experiment is to verify the Stefan-
More informationATMOS 5140 Lecture 7 Chapter 6
ATMOS 5140 Lecture 7 Chapter 6 Thermal Emission Blackbody Radiation Planck s Function Wien s Displacement Law Stefan-Bolzmann Law Emissivity Greybody Approximation Kirchhoff s Law Brightness Temperature
More informationRadiation Heat Transfer. Introduction. Blackbody Radiation
Radiation Heat Transfer Reading Problems 21-1 21-6 21-21, 21-24, 21-41, 21-61, 21-69 22-1 21-5 22-11, 22-17, 22-26, 22-36, 22-71, 22-72 Introduction It should be readily apparent that radiation heat transfer
More informationRadiative heat transfer
Radiative heat transfer 22 mars 2017 Energy can be transported by the electromagnetic field radiated by an object at finite temperature. A very important example is the infrared radiation emitted towards
More informationBeer-Lambert (cont.)
The Beer-Lambert Law: Optical Depth Consider the following process: F(x) Absorbed flux df abs F(x + dx) Scattered flux df scat x x + dx The absorption or scattering of radiation by an optically active
More informationSOLUTIONS. F 0 λ1 T = (1) F 0 λ2 T = (2) ε = (6) F 0 λt = (7) F 0 λt = (11)
Federal University of Rio Grande do Sul Mechanical Engineering Department MEC0065 - Thermal Radiation Professor - Francis Name: Márleson Rôndiner dos Santos Ferreira SOLUTIONS Question 2-5: The total hemispherical
More informationENSC 388. Assignment #8
ENSC 388 Assignment #8 Assignment date: Wednesday Nov. 11, 2009 Due date: Wednesday Nov. 18, 2009 Problem 1 A 3-mm-thick panel of aluminum alloy (k = 177 W/m K, c = 875 J/kg K, and ρ = 2770 kg/m³) is finished
More informationQUESTION ANSWER. . e. Fourier number:
QUESTION 1. (0 pts) The Lumped Capacitance Method (a) List and describe the implications of the two major assumptions of the lumped capacitance method. (6 pts) (b) Define the Biot number by equations and
More informationPROBLEM 1.2 ( ) 25 C 15 C dx L 0.30 m Ambient air temperature, T2 (C)
PROBLEM 1.2 KNOWN: Inner surface temperature and thermal conductivity of a concrete wall. FIND: Heat loss by conduction through the wall as a function of ambient air temperatures ranging from -15 to 38
More informationWhich picture shows the larger flux of blue circles?
Which picture shows the larger flux of blue circles? 33% 33% 33% 1. Left 2. Right 3. Neither Left Right Neither This Week: Global Climate Model Pt. 1 Reading: Chapter 3 Another Problem Set Coming Towards
More informationRadiation in climate models.
Lecture. Radiation in climate models. Objectives:. A hierarchy of the climate models.. Radiative and radiative-convective equilibrium.. Examples of simple energy balance models.. Radiation in the atmospheric
More informationThermal Radiation By: Prof. K M Joshi
Thermal Radiation By: Prof. K M Joshi Radiation originate due to emission of matter and its subsequent transports does not required any matter / medium. Que: Then what is the nature of this transport???
More informationAbsorptivity, Reflectivity, and Transmissivity
cen54261_ch21.qxd 1/25/4 11:32 AM Page 97 97 where f l1 and f l2 are blackbody functions corresponding to l 1 T and l 2 T. These functions are determined from Table 21 2 to be l 1 T (3 mm)(8 K) 24 mm K
More informationMASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics Problem Solving 10: The Greenhouse Effect. Section Table and Group
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.02 Problem Solving 10: The Greenhouse Effect Section Table and Group Names Hand in one copy per group at the end of the Friday Problem Solving
More informationGlobal Energy Balance. GEOG/ENST 2331: Lecture 4 Ahrens: Chapter 2
Global Energy Balance GEOG/ENST 2331: Lecture 4 Ahrens: Chapter 2 Solstices and Equinoxes Winter Solstice was on December 21 last year 8 hours 22 minutes of daylight March (Vernal) Equinox: March 20 this
More informationAtmospheric "greenhouse effect" - How the presence of an atmosphere makes Earth's surface warmer
Atmospheric "greenhouse effect" - How the presence of an atmosphere makes Earth's surface warmer Some relevant parameters and facts (see previous slide sets) (So/) 32 W m -2 is the average incoming solar
More informationINTRODUCTION Radiation differs from conduction and convection in that it does not require the presence of a material medium to take place.
RADIATION INTRODUCTION Radiation differs from conduction and convection in that it does not require the presence of a material medium to take place. Radiation: The energy emitted by matter in the form
More informationSources of radiation
Sources of radiation Most important type of radiation is blackbody radiation. This is radiation that is in thermal equilibrium with matter at some temperature T. Lab source of blackbody radiation: hot
More informationME 476 Solar Energy UNIT TWO THERMAL RADIATION
ME 476 Solar Energy UNIT TWO THERMAL RADIATION Unit Outline 2 Electromagnetic radiation Thermal radiation Blackbody radiation Radiation emitted from a real surface Irradiance Kirchhoff s Law Diffuse and
More informationFriday 8 September, :00-4:00 Class#05
Friday 8 September, 2017 3:00-4:00 Class#05 Topics for the hour Global Energy Budget, schematic view Solar Radiation Blackbody Radiation http://www2.gi.alaska.edu/~bhatt/teaching/atm694.fall2017/ notes.html
More informationAtmospheric "greenhouse effect" - How the presence of an atmosphere makes Earth's surface warmer
Atmospheric "greenhouse effect" - How the presence of an atmosphere makes Earth's surface warmer Some relevant parameters and facts (see previous slide sets) (So/) 32 W m -2 is the average incoming solar
More informationMNFFY 221/SIF 4082 Energy and Environmental Physics. 2002
MNFFY 221/SIF 4082 Energy and Environmental Physics. 2002 Suggested solution to exam Problem 2 a) Show that the energy received from the sun earth is on average equal to the solar constant S given by 1
More informationINFRAMET. 2.1 Basic laws
tel: 048 60844873, fax 48 6668780. Basic laws.. Planck law All objects above the temperature of absolute zero emit thermal radiation due to thermal motion of the atoms and the molecules. The hotter they
More informationHeat and Mass Transfer Unit-1 Conduction
1. State Fourier s Law of conduction. Heat and Mass Transfer Unit-1 Conduction Part-A The rate of heat conduction is proportional to the area measured normal to the direction of heat flow and to the temperature
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Clouds Meteorology Photochemistry Atmospheric Escape EAS 4803/8803 - CP 11:1 Structure Generalized Hydrostatic Equilibrium P( z) = P( 0)e z # ( ) " dr / H r
More informationRadiation from planets
Chapter 4 Radiation from planets We consider first basic, mostly photometric radiation parameters for solar system planets which can be easily compared with existing or future observations of extra-solar
More informationReview: Conduction. Breaking News
CH EN 3453 Heat Transfer Review: Conduction Breaking News No more homework (yay!) Final project reports due today by 8:00 PM Email PDF version to report@chen3453.com Review grading rubric on Project page
More informationThermal Systems. What and How? Physical Mechanisms and Rate Equations Conservation of Energy Requirement Control Volume Surface Energy Balance
Introduction to Heat Transfer What and How? Physical Mechanisms and Rate Equations Conservation of Energy Requirement Control Volume Surface Energy Balance Thermal Resistance Thermal Capacitance Thermal
More informationPaper No. : 04 Paper Title: Unit Operations in Food Processing Module-07: Heat Transfer 3: Heat Radiation
Paper No. : 04 Paper Title: Unit Operations in Food Processing Module-07: Heat Transfer 3: Heat Radiation 7.1 Introduction Radiation heat transfer is the transfer of heat energy in the form of electromagnetic
More informationProblem Set 2 Solutions
Problem Set 2 Solutions Problem 1: A A hot blackbody will emit more photons per unit time per unit surface area than a cold blackbody. It does not, however, necessarily need to have a higher luminosity,
More informationLecture 4: Radiation Transfer
Lecture 4: Radiation Transfer Spectrum of radiation Stefan-Boltzmann law Selective absorption and emission Reflection and scattering Remote sensing Importance of Radiation Transfer Virtually all the exchange
More informationChapter 1: 20, 23, 35, 41, 68, 71, 76, 77, 80, 85, 90, 101, 103 and 104.
Chapter 1: 0, 3, 35, 1, 68, 71, 76, 77, 80, 85, 90, 101, 103 and 10. 1-0 The filament of a 150 W incandescent lamp is 5 cm long and has a diameter of 0.5 mm. The heat flux on the surface of the filament,
More informationPROBLEM 1.3. dt T1 T dx L 0.30 m
PROBLEM 1.3 KNOWN: Inner surface temperature and thermal conductivity of a concrete wall. FIND: Heat loss by conduction through the wall as a function of outer surface temperatures ranging from -15 to
More informationUniversity of New Mexico Mechanical Engineering Fall 2012 PhD qualifying examination Heat Transfer
University of New Mexico Mechanical Engineering Fall 2012 PhD qualifying examination Heat Transfer Closed book. Formula sheet and calculator are allowed, but not cell phones, computers or any other wireless
More informationE d. h, c o, k are all parameters from quantum physics. We need not worry about their precise definition here.
The actual form of Plank s law is: b db d b 5 e C C2 1 T 1 where: C 1 = 2hc o 2 = 3.7210 8 Wm /m 2 C 2 = hc o /k = 1.3910 mk Where: h, c o, k are all parameters from quantum physics. We need not worry
More informationReview from last class:
Review from last class: Properties of photons Flux and luminosity, apparent magnitude and absolute magnitude, colors Spectroscopic observations. Doppler s effect and applications Distance measurements
More informationaka Light Properties of Light are simultaneously
Today Interaction of Light with Matter Thermal Radiation Kirchhoff s Laws aka Light Properties of Light are simultaneously wave-like AND particle-like Sometimes it behaves like ripples on a pond (waves).
More informationStefan-Boltzmann law for the Earth as a black body (or perfect radiator) gives:
2. Derivation of IPCC expression ΔF = 5.35 ln (C/C 0 ) 2.1 Derivation One The assumptions we will make allow us to represent the real atmosphere. This remarkably reasonable representation of the real atmosphere
More informationUniversity of New Mexico Mechanical Engineering Spring 2012 PhD qualifying examination Heat Transfer
University of New Mexico Mechanical Engineering Spring 2012 PhD qualifying examination Heat Transfer Closed book. Formula sheet and calculator are allowed, but not cell phones, computers or any other wireless
More informationTHE EXOSPHERIC HEAT BUDGET
E&ES 359, 2008, p.1 THE EXOSPHERIC HEAT BUDGET What determines the temperature on earth? In this course we are interested in quantitative aspects of the fundamental processes that drive the earth machine.
More informationAstro 210 Lecture 16 Feb 23, 2018
Astro 210 Lecture 16 Feb 23, 2018 Announcements HW4 due online in PDF, Today 5:00 pm HW5 posted today, due online next Friday Night Observing next week...weather permitting Campus Observatory. Mon, Tue,
More informationChapter 18 Temperature, Heat, and the First Law of Thermodynamics. Thermodynamics and Statistical Physics
Chapter 18 Temperature, Heat, and the First Law of Thermodynamics Thermodynamics and Statistical Physics Key contents: Temperature scales Thermal expansion Temperature and heat, specific heat Heat and
More informationHand in Question sheets with answer booklets Calculators allowed Mobile telephones or other devices not allowed
York University Department of Earth and Space Science and Engineering ESSE 3030 Department of Physics and Astronomy PHYS 3080 Atmospheric Radiation and Thermodynamics Final Examination 2:00 PM 11 December
More informationPlanetary Atmospheres
Planetary Atmospheres Structure Composition Clouds Meteorology Photochemistry Atmospheric Escape EAS 4803/8803 - CP 17:1 Structure Generalized Hydrostatic Equilibrium P( z) = P( 0)e z # ( ) " dr / H r
More informationElectromagnetic Radiation. Radiation and the Planetary Energy Balance. Electromagnetic Spectrum of the Sun
Radiation and the Planetary Energy Balance Electromagnetic Radiation Solar radiation warms the planet Conversion of solar energy at the surface Absorption and emission by the atmosphere The greenhouse
More informationTransport processes. 7. Semester Chemical Engineering Civil Engineering
Transport processes 7. Semester Chemical Engineering Civil Engineering 1. Elementary Fluid Dynamics 2. Fluid Kinematics 3. Finite Control Volume Analysis 4. Differential Analysis of Fluid Flow 5. Viscous
More informationTransient Heat Transfer Experiment. ME 331 Introduction to Heat Transfer. June 1 st, 2017
Transient Heat Transfer Experiment ME 331 Introduction to Heat Transfer June 1 st, 2017 Abstract The lumped capacitance assumption for transient conduction was tested for three heated spheres; a gold plated
More informationMeasuring the Temperature of the Sun
Measuring the Temperature of the Sun Purpose: In this lab you will measure the solar flux, the amount of energy per unit area per unit time that reaches the Earth from the Sun. From this, you will calculate
More informationReading Problems , 15-33, 15-49, 15-50, 15-77, 15-79, 15-86, ,
Radiation Heat Transfer Reading Problems 15-1 15-7 15-27, 15-33, 15-49, 15-50, 15-77, 15-79, 15-86, 15-106, 15-107 Introduction The following figure shows the relatively narrow band occupied by thermal
More informationIf there is convective heat transfer from outer surface to fluid maintained at T W.
Heat Transfer 1. What are the different modes of heat transfer? Explain with examples. 2. State Fourier s Law of heat conduction? Write some of their applications. 3. State the effect of variation of temperature
More informationOPTIMIZATION of the GEOMETRY & MATERIAL of SOLAR WATER HEATERS.
OPTIMIZATION of the GEOMETRY & MATERIAL of SOLAR WATER HEATERS. FLAT PLATE COLLECTORS ABSORBER PLATES OPTIMIZATION OF GEOMETRY SELECTIVE SURFACES METHODS OF TESTING TO DETERMINE THE THERMAL PERFORMANCE
More informationThe Tropical Atmosphere: Hurricane Incubator
The Tropical Atmosphere: Hurricane Incubator Images from journals published by the American Meteorological Society are copyright AMS and used with permission. A One-Dimensional Description of the Tropical
More informationTime-Dependent Conduction :
Time-Dependent Conduction : The Lumped Capacitance Method Chapter Five Sections 5.1 thru 5.3 Transient Conduction A heat transfer process for which the temperature varies with time, as well as location
More informationLECTURE NOTES. Heat Transfer. III B. Tech II Semester (JNTUA-R15) CHADALAWADA RAMANAMMA ENGINEERING COLLEGE (AUTONOMOUS)
LECTURE NOTES on Heat Transfer III B. Tech II Semester (JNTUA-R15) Mr. K.SURESH, Assistant Professor CHADALAWADA RAMANAMMA ENGINEERING COLLEGE (AUTONOMOUS) Chadalawada Nagar, Renigunta Road, Tirupati 517
More information2. Energy Balance. 1. All substances radiate unless their temperature is at absolute zero (0 K). Gases radiate at specific frequencies, while solids
I. Radiation 2. Energy Balance 1. All substances radiate unless their temperature is at absolute zero (0 K). Gases radiate at specific frequencies, while solids radiate at many Click frequencies, to edit
More informationLecture 3: Emission and absorption
Lecture 3: Emission and absorption Senior Astrophysics 2017-03-10 Senior Astrophysics Lecture 3: Emission and absorption 2017-03-10 1 / 35 Outline 1 Optical depth 2 Sources of radiation 3 Blackbody radiation
More informationHeat Transfer: A Practical Approach - Yunus A Cengel Assignment 11 Fall 2003 Tuesday, November 18, 2003 Chapter 11, Problem 49
Heat Transer: A Practical Approach - Yunus A Cengel Assignment Fall 00 Tuesday, November 8, 00 Chapter, Problem 9 The variation o the spectral transmissivity o a 0.6- cm-thick glass window is as given
More informationAtomic Physics 3 ASTR 2110 Sarazin
Atomic Physics 3 ASTR 2110 Sarazin Homework #5 Due Wednesday, October 4 due to fall break Test #1 Monday, October 9, 11-11:50 am Ruffner G006 (classroom) You may not consult the text, your notes, or any
More informationWith certain caveats (described later) an object absorbs as effectively as it emits
Figure 1: A blackbody defined by a cavity where emission and absorption are in equilibrium so as to maintain a constant temperature Blackbody radiation The basic principles of thermal emission are as follows:
More informationName... Class... Date...
Radiation and temperature Specification reference: P6.3 Black body radiation (physics only) Aims This is an activity that has been designed to help you improve your literacy skills. In this activity you
More informationThe Nature of Light I: Electromagnetic Waves Spectra Kirchoff s Laws Temperature Blackbody radiation
The Nature of Light I: Electromagnetic Waves Spectra Kirchoff s Laws Temperature Blackbody radiation Electromagnetic Radiation (How we get most of our information about the cosmos) Examples of electromagnetic
More informationEART164: PLANETARY ATMOSPHERES
EART16: PLANETARY ATMOSPHERES Francis Nimmo Last Week How do planets form? They accrete from the solar nebula (dust+gas) They may subsequently migrate Where do atmospheres come from? Primary, secondary,
More informationLet s make a simple climate model for Earth.
Let s make a simple climate model for Earth. What is the energy balance of the Earth? How is it controlled? ó How is it affected by humans? Energy balance (radiant energy) Greenhouse Effect (absorption
More informationEarth: the Goldilocks Planet
Earth: the Goldilocks Planet Not too hot (460 C) Fig. 3-1 Not too cold (-55 C) Wave properties: Wavelength, velocity, and? Fig. 3-2 Reviewing units: Wavelength = distance (meters or nanometers, etc.) Velocity
More informationinnova-ve entrepreneurial global 1
www.utm.my innova-ve entrepreneurial global 1 The science of how heat flows is called heat transfer. There are three ways heat transfer works: conduction, convection, and radiation. Heat flow depends on
More informationThermodynamics 1. Lecture 7: Heat transfer Open systems. Bendiks Jan Boersma Thijs Vlugt Theo Woudstra. March 1, 2010.
hermodynamics Lecture 7: Heat transfer Open systems Bendiks Jan Boersma hijs Vlugt heo Woudstra March, 00 Energy echnology Summary lecture 6 Poisson relation efficiency of a two-stroke IC engine (Otto
More informationEquation for Global Warming
Equation for Global Warming Derivation and Application Contents 1. Amazing carbon dioxide How can a small change in carbon dioxide (CO 2 ) content make a critical difference to the actual global surface
More informationChapter 18. Temperature, Heat, and the First Law of Thermodynamics Temperature
Chapter 18 Temperature, Heat, and the First Law of Thermodynamics 18.2 Temperature 18.3: The Zeroth aw of Thermodynamics If bodies A and B are each in thermal equilibrium with a third body T, then A and
More informationProblem One Answer the following questions concerning fundamental radiative heat transfer. (2 points each) Part Question Your Answer
Problem One Answer the following questions concerning fundamental radiative heat transfer. ( points each) Part Question Your Answer A Do all forms of matter emit radiation? Yes B Does the transport of
More informationChapter 1 INTRODUCTION AND BASIC CONCEPTS
Heat and Mass Transfer: Fundamentals & Applications 5th Edition in SI Units Yunus A. Çengel, Afshin J. Ghajar McGraw-Hill, 2015 Chapter 1 INTRODUCTION AND BASIC CONCEPTS Mehmet Kanoglu University of Gaziantep
More information= (fundamental constants c 0, h, k ). (1) k
Introductory Physics Laboratory, Faculty of Physics and Geosciences, University of Leipzig W 12e Radiation Thermometers Tasks 1 Measure the black temperature T s of a glowing resistance wire at eight different
More informationSimplified Collector Performance Model
Simplified Collector Performance Model Prediction of the thermal output of various solar collectors: The quantity of thermal energy produced by any solar collector can be described by the energy balance
More informationEXPERIMENT NO. 4. Thermal Radiation: the Stefan-Boltzmann Law
1 EXPERIMENT NO. 4 Thermal Radiation: the Stefan-Boltzmann Law References: Physics for Scientists and Engineers, Serway and Jewett. Sections 40.1 An Introduction to Thermal Physics, Schroeder, Section
More information1. Weather and climate.
Lecture 31. Introduction to climate and climate change. Part 1. Objectives: 1. Weather and climate. 2. Earth s radiation budget. 3. Clouds and radiation field. Readings: Turco: p. 320-349; Brimblecombe:
More informationEquilibrium Properties of Matter and Radiation
Equilibrium Properties of Matter and Radiation Temperature What is it? A measure of internal energy in a system. Measure from (1) velocities of atoms/molecules () population of excited/ionized states (3)
More informationSpectroscopy Lecture 2
Spectroscopy Lecture 2 I. Atomic excitation and ionization II. Radiation Terms III. Absorption and emission coefficients IV. Einstein coefficients V. Black Body radiation I. Atomic excitation and ionization
More informationToday. Spectra. Thermal Radiation. Wien s Law. Stefan-Boltzmann Law. Kirchoff s Laws. Emission and Absorption. Spectra & Composition
Today Spectra Thermal Radiation Wien s Law Stefan-Boltzmann Law Kirchoff s Laws Emission and Absorption Spectra & Composition Spectrum Originally, the range of colors obtained by passing sunlight through
More informationChapter 4: Transient Heat Conduction. Dr Ali Jawarneh Department of Mechanical Engineering Hashemite University
Chapter 4: Transient Heat Conduction Dr Ali Jawarneh Department of Mechanical Engineering Hashemite University Objectives When you finish studying this chapter, you should be able to: Assess when the spatial
More informationRadiative Transfer Chapter 3, Hartmann
Radiative Transfer Chapter 3, Hartmann Shortwave Absorption: Clouds, H 2 0, O 3, some CO 2 Shortwave Reflection: Clouds, surface, atmosphere Longwave Absorption: Clouds, H 2 0, CO 2, CH 4, N 2 O Planck
More informationdi λ ds = ρk λi λ B λ (T ) + ρk λ dz' )= B λ (T(z'))e I λ (z TOA + k λ Longwave radiative transfer Longwave radiative transfer
Radiative transfer applied to the atmosphere: Longwave radiation z In the longwave spectrum (> µm) we have to take into account both absorption and emission, as the atmosphere and Earth surface with temperatures
More informationTo remain at 0 K heat absorbed by the medium must be removed in the amount of. dq dx = q(l) q(0) dx. Q = [1 2E 3 (τ L )] σ(t T 4 2 ).
294 RADIATIVE HEAT TRANSFER 13.7 Two infinite, isothermal plates at temperatures T 1 and T 2 are separated by a cold, gray medium of optical thickness τ L = L (no scattering). (a) Calculate the radiative
More informationUNIT FOUR SOLAR COLLECTORS
ME 476 Solar Energy UNIT FOUR SOLAR COLLECTORS Flat Plate Collectors Outline 2 What are flat plate collectors? Types of flat plate collectors Applications of flat plate collectors Materials of construction
More informationDescription of radiation field
Description of radiation field Qualitatively, we know that characterization should involve energy/time frequency all functions of x,t. direction We also now that radiation is not altered by passing through
More informationATMO 551a Intro to Optical Depth Fall τ υ,z. dz = di υ. B[ v,t(z) ]e
Atmospheric Radiative Transfer We need to understand how energy is transferred via radiation within the atmosphere. We introduce the concept of optical depth. We will further show that the light moves
More informationUniversity of Rome Tor Vergata
University of Rome Tor Vergata Faculty of Engineering Department of Industrial Engineering THERMODYNAMIC AND HEAT TRANSFER HEAT TRANSFER dr. G. Bovesecchi gianluigi.bovesecchi@gmail.com 06-7259-727 (7249)
More information