The Three Heat Transfer Modes in Reflow Soldering
|
|
- Blanche Flowers
- 7 years ago
- Views:
Transcription
1 Section 5: Reflow Oven Heat Transfer The Three Heat Transfer Modes in Reflow Soldering There are three different heating modes involved with most SMT reflow processes: conduction, convection, and infrared radiation (IR). All three of these heating modes occur naturally in our daily lives. Perhaps the easiest way to understand each of these heating modes is through example. Hot Spot Heat Flow Heat Flows From Hot to Cold To Help Equalize Temperatures Figure 5-1. Example of conduction heat transfer. Cold Spot heat transfer occurs when two solid masses of different temperatures are in contact with each other. A good example is when a pan is placed on an electric burner. Most of the heat is transferred to the pan by the contact between the pan and the burner. also occurs within the same mass if a temperature differential exists within the mass. can both help and hinder the SMT reflow process. helps in uniform product heating, as heat will conduct from a hot spot to a cold spot in the product. Thus, if a product is difficult to reflow, often a good solution is to reduce the oven heater setpoint temperatures and conveyor speed. This allows more time for the conductive flow to occur and the product will heat more uniformly. hinders the process if an edge conveyor in contact with the board is cooler or hotter than the product. heat transfer can result in a hot or cool spot along the edge of the product, preventing uniform solder joints on the outer fringes of the PCB. Infrared Infrared Radiation (IR) occurs when two bodies of different temperatures are in sight of each other. The best example of IR is the heating of the earth by the sun. Dull, rough surfaces absorb the sun s rays better than shiny, smooth surfaces. An object in the direct sun light will become hotter than if in the shade. Radiation Sun Radiant Energy From The Sun Heats The Earth Figure 5-2. Example of infrared radiation. Research International Page 22
2 IR in SMT applications works similarly. Fluxes, plastic components, and epoxy glass laminate absorb IR very well. Shiny, reflowed solder will reflect the IR energy away. Solder joints around small packages (such as chip resistors, capacitors, and SOIC s) are in sight of the IR energy and heat very well. Solder joints around larger devices (such as PLCC s) are shaded, and do not heat as well. heat transfer occurs when a fluid (such as air, nitrogen, or water) passes over an object (such as an SMT assembly). A cool breeze on a hot sunny day provides convective cooling. Hot air from a hair dryer provides convective heating. heating or cooling requires contact of the flow with the solid part. Only the layer of the flow that is in contact with the part is actually transferring heat. may be classified as natural or forced. Natural convection occurs when no flow is being forced over the object. Temperature differences between the object and the environment create the convective heat transfer. Perhaps the best example is the chimney effect, where a strong convective current rises away from the hot embers to the cooler outdoors. Forced convection requires an external force that pushes or pulls the flow over the object. A common house fan is a good example. Hot Air Flow Cold Object Is Heated By From The Hot Air Flow Figure 5-3. Example of convection heat transfer. Typically, forced convection heating or cooling rates are higher than natural convection rates. Most reflow ovens today use forced convection as the primary heat transfer mode. Research International won the 1998 SMT Magazine Vision Award for advances in Soldering Equipment. Notes: Page 23 Research International
3 Heat Transfer Equations In order to understand what parameters are important in conduction heat transfer, one can consider the variables in the general conduction heat transfer equation. Q = K * A * ( T 1 - T 2 ) / X Q = heat transfer (W ) A = Cross sectional area (cm 2 ) K = Thermal conductivity (W/cm - C) T 1 = Temperature at point 1 ( C) T 2 = Temperature at point 2 ( C) X = Thickness of material between points 1 and 2 (cm) The thermal conductivity (K) is a measure of how well the object conducts heat. Insulators (such as epoxy glass) have very low thermal conductivity and permit very low amounts of conductive heat transfer. Conductors (such as copper) have a very high thermal conductivity and permit high amounts of conductive heat transfer. Thus, an SMT assembly with high amounts of copper will heat more uniformly than one without much copper. through the circuit board during the reflow process improves heating uniformity, as the heat conducts from the hot spots to the cold spots. t 1 k = Thermal Conductivity Surface 1 Surface 2 Conductive heat transfer is proportional to the cross sectional area (A) between point 1 and point 2. In SMT reflow, a thicker board will provide greater populated uniformity than a thin board since the cross sectional area is greater. Conductive heat transfer is also dependent upon the distance between point 1 and point 2 ( X). The greater the distance, the less the heat transfer. Thus, a thicker board has a better chance of maintaining a higher temperature difference between the top and bottom side of the board than a thin board. IR - Infrared Infrared (IR) heat transfer occurs when two objects at different temperatures are in sight of each other. The heat is transferred by electromagnetic waves of 0.78 to 1000 micron wavelengths. All objects emit some level of infrared energy. The quantity of infrared energy emitted and the wavelength of the emission are both dependent upon the absolute temperature of the object. As the source temperature increases, the heat transfer output increases exponentially to the fourth power. Increasing the source temperature results in shorter wavelengths. Decreasing the source temperature results in longer wavelengths. In order to understand what parameters are important in infrared heating, one can consider the general equation for heat transfer between the heat source and the object being heated. The purpose is not to memorize the equation, but rather to point out the significance of what is involved. t 2 x Figure 5-4. heat transfer model. Research International Page 24
4 The general equation for infrared heat transfer is: Q/A = F v * ε s * α t σ * ( T s 4 - T t 4 ) Q/A = Infrared heat transfer (W/cm 2 ) F v = Geometric view factor (0-1) ε s = Emmissivity of the source (0-1) α t = Absorptivity of the target (0-1) σ = Stefan-Boltzmann Constant (5.67 x W/cm 2 / K 4 ) T s = Source temperature ( K) = Target temperature ( K) T t IR Source Control of infrared is generally done by controlling the source temperature. Providing that the overall source emission can be regulated, IR energy provides high levels of repeatability. heat transfer occurs when a fluid at a given temperature contacts a solid mass at a different temperature. If the fluid is hotter than the mass, the mass will be heated. If the fluid is cooler than the mass, the mass will be cooled. Perhaps the easiest way to understand convection is to look at the convection equation and note the significance of each variable. The following is the general equation for convection heating or cooling: This Area is Shaded by Adjacent Components Resulting in a Lower View Factor Figure 5-5. IR view factor. The geometric view factor F v is the fraction of energy that leaves the source that hits the target. In SMT reflow, the oven chamber designs yield very high view factors in the range of 0.90 to An important aspect of the view factor comes in product design. If two very large components are in close proximity to each other, the view factor to a solder joint between them is decreased, which makes it more difficult to reflow. The source emissivity (ε s ) and the target absorptivity factors (α t ) are in the range of 0.90 to 0.95 for most SMT applications. Solder paste is an excellent absorber of infrared energy. Shiny gold components may be difficult to heat, as they tend to be reflective. Most often, however, the board material, solder paste, and the components all absorb quite well. Q/A = H * (T a - T t ) Q/A = heat transfer per unit area (W/cm 2 ) H = Convective film coefficient (W/cm 2 - C) T a = Fluid temperature ( C) = Target temperature ( C) T t The amount of heat transfer can be modified by either changing the convective coefficient (H) or the temperature difference (T a - T t ). Increasing the fluid temperature will increase the temperature difference, and thus the amount of heat transfer will increase proportionally. The convective coefficient (H) can have a significant impact on the heat transfer. The value of H is related to a number of variables, including velocity of the flow and angle of attack of the flow. Increasing the flow velocity will increase the value of H. For example, when one is outside in the wind, a low velocity cool breeze on a warm day will feel quite nice. However, a strong wind on that same day may feel very cold. Page 25 Research International
5 That is because the higher velocity wind has a higher convective coefficient, and thus removes heat more effectively from your skin. In SMT reflow applications, increasing the velocity of the flow also improves the amount of convection heat transfer. There are practical limits to this, as too high velocity may cause components to shift around. Parallel Flow Air Velocity (V) At Surface, V=0 Perpendicular Flow Surface Agitation Prevents Boundary Layer Buildup Air Velocity (V) Figure 5-6. Fluid flow patterns. Boundary Layer Thickness The flow direction also has a significant impact on H. heat transfer relies on contact between the flow and the object. Parallel flow can result in a stagnation or boundary layer in which the heat transfer is diminished. Perpendicular flow can break up formation of a boundary layer and enhance the convective heat transfer. Perpendicular flow thus provides higher heat transfer rates than parallel flow. Heat Transfer Mode Interaction and their Effect on SMT Reflow In SMT reflow applications, there is no such thing as pure convection or pure IR. The only way to achieve a 100% convection system would be to have gas flowing over the product with no chamber walls inside the reflow oven. Obviously the reflow oven is a mechanical device with walls that absorb or emit heat, so 100% convection is a physical impossbility. To have a 100% IR reflow system, the chamber would need to be operated in a vacuum (no air fluid heat transfer). Most reflow processes currently occur in some process gas whether air, nitrogen or vapor phase techniques. However, reflow oven heat transfer designs utilize a greater convection component, while others utilize IR as the primary heat source. For the sake of simplicity, this text will refer to a convection dominate heat transfer machine as a convection machine, and an IR dominated machine as an IR machine. In SMT reflow applications (with the exception of vapor phase), convection, conduction, and IR all play a role in the heating process. Referring to a system as 100% convection or 100% IR is an error in terminology. An oven may be dominated by convection or IR, but the other heat transfer is always present. IR dominant systems usually range in the convection/ir ratio of 60/40 to 40/60. dominant systems have ratios in the range of 70/30 to 90/10. Research International Page 26
Energy and Energy Transformations Test Review
Energy and Energy Transformations Test Review Completion: 1. Mass 13. Kinetic 2. Four 14. thermal 3. Kinetic 15. Thermal energy (heat) 4. Electromagnetic/Radiant 16. Thermal energy (heat) 5. Thermal 17.
More informationGreenhouse Glazing Effects on Heat Transfer for Winter Heating and Summer Cooling
Greenhouse Glazing Effects on Heat Transfer for Winter Heating and Summer Cooling David R. Mears, Ph.D. Bioresource Engineering Department of Plant Biology and Pathology Rutgers University 20 Ag Extension
More informationChapter 4: Transfer of Thermal Energy
Chapter 4: Transfer of Thermal Energy Goals of Period 4 Section 4.1: To define temperature and thermal energy Section 4.2: To discuss three methods of thermal energy transfer. Section 4.3: To describe
More informationEnergy Transport. Focus on heat transfer. Heat Transfer Mechanisms: Conduction Radiation Convection (mass movement of fluids)
Energy Transport Focus on heat transfer Heat Transfer Mechanisms: Conduction Radiation Convection (mass movement of fluids) Conduction Conduction heat transfer occurs only when there is physical contact
More informationForms of Energy. Freshman Seminar
Forms of Energy Freshman Seminar Energy Energy The ability & capacity to do work Energy can take many different forms Energy can be quantified Law of Conservation of energy In any change from one form
More informationConvection, Conduction & Radiation
Convection, Conduction & Radiation There are three basic ways in which heat is transferred: convection, conduction and radiation. In gases and liquids, heat is usually transferred by convection, in which
More informationName: Class: Date: 10. Some substances, when exposed to visible light, absorb more energy as heat than other substances absorb.
Name: Class: Date: ID: A PS Chapter 13 Review Modified True/False Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true. 1. In all cooling
More information1/9/2013. Terminology Calculating Heat Transfer Code Requirements Design Examples and Sustainability
1/9/13 By Brett T. Fagan, P.E. Presented by Marie Horan, P.E. Building Diagnostics, Inc. Building Diagnostics Terminology Calculating Heat Transfer Code Requirements Design Examples and Sustainability
More informationWhat Is Heat? What Is Heat?
What Is Heat? Paul shivered inside the wood cabin. It was cold outside, and inside the cabin it wasn t much warmer. Paul could hear the rain beating down on the roof. Every few minutes there would be a
More information1. At which temperature would a source radiate the least amount of electromagnetic energy? 1) 273 K 3) 32 K 2) 212 K 4) 5 K
1. At which temperature would a source radiate the least amount of electromagnetic energy? 1) 273 K 3) 32 K 2) 212 K 4) 5 K 2. How does the amount of heat energy reflected by a smooth, dark-colored concrete
More informationChapter 18 Temperature, Heat, and the First Law of Thermodynamics. Problems: 8, 11, 13, 17, 21, 27, 29, 37, 39, 41, 47, 51, 57
Chapter 18 Temperature, Heat, and the First Law of Thermodynamics Problems: 8, 11, 13, 17, 21, 27, 29, 37, 39, 41, 47, 51, 57 Thermodynamics study and application of thermal energy temperature quantity
More informationLecture 30 - Chapter 6 Thermal & Energy Systems (Examples) 1
Potential Energy ME 101: Thermal and Energy Systems Chapter 7 - Examples Gravitational Potential Energy U = mgδh Relative to a reference height Increase in elevation increases U Decrease in elevation decreases
More informationCPI Links Content Guide & Five Items Resource
CPI Links Content Guide & Five Items Resource Introduction The following information should be used as a companion to the CPI Links. It provides clarifications concerning the content and skills contained
More informationa) species of plants that require a relatively cool, moist environment tend to grow on poleward-facing slopes.
J.D. McAlpine ATMS 611 HMWK #8 a) species of plants that require a relatively cool, moist environment tend to grow on poleward-facing slopes. These sides of the slopes will tend to have less average solar
More informationChapter 2: Solar Radiation and Seasons
Chapter 2: Solar Radiation and Seasons Spectrum of Radiation Intensity and Peak Wavelength of Radiation Solar (shortwave) Radiation Terrestrial (longwave) Radiations How to Change Air Temperature? Add
More informationTech Bulletin. Understanding Solar Performance
Tech Bulletin Understanding Solar Performance Bekaert solar control window films use advanced technology to benefit consumers with quality solutions that enhance comfort and decrease energy use. By understanding
More informationTOPIC 5 (cont.) RADIATION LAWS - Part 2
TOPIC 5 (cont.) RADIATION LAWS - Part 2 Quick review ELECTROMAGNETIC SPECTRUM Our focus in this class is on: UV VIS lr = micrometers (aka microns) = nanometers (also commonly used) Q1. The first thing
More informationSOLAR ENERGY How much strikes the earth? How much can my building get? When is it too much?
SOLAR ENERGY How much strikes the earth? How much can my building get? When is it too much? The sun: friend of foe? Drawing by Le Corbusier ENGS 44 Sustainable Design Benoit Cushman-Roisin 14 April 2015
More informationPOROUS BURNER - A New Approach to Infrared
Page: 1 POROUS BURNER - A New Approach to Infrared 1. Preface There are several possibilities to produce infrared radiation in the technical sense. Regarding the source of energy you can distinguish between
More information8001782 Owner s Manual
8001782 Digital Infrared Thermometer Owner s Manual Introduction This instrument is a portable, easy to use compact-size digital thermometer with laser sighting designed for one hand operation. The meter
More informationTEACHER BACKGROUND INFORMATION THERMAL ENERGY
TEACHER BACKGROUND INFORMATION THERMAL ENERGY In general, when an object performs work on another object, it does not transfer all of its energy to that object. Some of the energy is lost as heat due to
More informationWhat is Solar Control?
A better environment inside and out. Solar, Safety and Security Window Films: Tech Bulletin Understanding Solar Performance Solar Gard solar control window films use advanced technology to benefit consumers
More informationPrinciple of Thermal Imaging
Section 8 All materials, which are above 0 degrees Kelvin (-273 degrees C), emit infrared energy. The infrared energy emitted from the measured object is converted into an electrical signal by the imaging
More informationSelective Soldering Defects and How to Prevent Them
Selective Soldering Defects and How to Prevent Them Gerjan Diepstraten Vitronics Soltec BV Introduction Two major issues affecting the soldering process today are the conversion to lead-free soldering
More informationComments on How Exterior Paints and Interior Paints Can Play Roles in Conserving Energy. For Tech Traders Inc. By H. F. Poppendiek
Comments on How Exterior Paints and Interior Paints Can Play Roles in Conserving Energy For Tech Traders Inc. By H. F. Poppendiek June 2002 GEOSCIENCE LTD 620 Marindustry Drive San Diego, California 92121
More informationCHAPTER 2 Energy and Earth
CHAPTER 2 Energy and Earth This chapter is concerned with the nature of energy and how it interacts with Earth. At this stage we are looking at energy in an abstract form though relate it to how it affect
More informationEvery mathematician knows it is impossible to understand an elementary course in thermodynamics. ~V.I. Arnold
Every mathematician knows it is impossible to understand an elementary course in thermodynamics. ~V.I. Arnold Radiation Radiation: Heat energy transmitted by electromagnetic waves Q t = εσat 4 emissivity
More informationAS COMPETITION PAPER 2007 SOLUTIONS
AS COMPETITION PAPER 2007 Total Mark/50 SOLUTIONS Section A: Multiple Choice 1. C 2. D 3. B 4. B 5. B 6. A 7. A 8. C 1 Section B: Written Answer Question 9. A mass M is attached to the end of a horizontal
More informationWindows are one of the most important components of a
design concepts Arjun Kamal MAKING BETTER INDOOR ENVIRONMENTS WITH ENERGY-EFFICIENT WINDOW DESIGN An insight into the various technologies used for constructing windows, and an attempt at understanding
More informationES 106 Laboratory # 2 HEAT AND TEMPERATURE
ES 106 Laboratory # 2 HEAT AND TEMPERATURE Introduction Heat transfer is the movement of heat energy from one place to another. Heat energy can be transferred by three different mechanisms: convection,
More informationHow To Calculate Thermal Resistance On A Pb (Plastipo)
VISHAY BEYSCHLAG Resistive Products 1. INTRODUCTION Thermal management is becoming more important as the density of electronic components in modern printed circuit boards (PCBs), as well as the applied
More informationAS COMPETITION PAPER 2008
AS COMPETITION PAPER 28 Name School Town & County Total Mark/5 Time Allowed: One hour Attempt as many questions as you can. Write your answers on this question paper. Marks allocated for each question
More informationTake away concepts. What is Energy? Solar Energy. EM Radiation. Properties of waves. Solar Radiation Emission and Absorption
Take away concepts Solar Radiation Emission and Absorption 1. 2. 3. 4. 5. 6. Conservation of energy. Black body radiation principle Emission wavelength and temperature (Wein s Law). Radiation vs. distance
More informationATM S 111, Global Warming: Understanding the Forecast
ATM S 111, Global Warming: Understanding the Forecast DARGAN M. W. FRIERSON DEPARTMENT OF ATMOSPHERIC SCIENCES DAY 1: OCTOBER 1, 2015 Outline How exactly the Sun heats the Earth How strong? Important concept
More informationVapor Chambers. Figure 1: Example of vapor chamber. Benefits of Using Vapor Chambers
Vapor Chambers A vapor chamber is a high-end thermal management device that can evenly dissipate heat from a small source to a large platform of area (see Figure 1). It has a similar construction and mechanism
More informationPractice Test. 4) The planet Earth loses heat mainly by A) conduction. B) convection. C) radiation. D) all of these Answer: C
Practice Test 1) Increase the pressure in a container of oxygen gas while keeping the temperature constant and you increase the A) molecular speed. B) molecular kinetic energy. C) Choice A and choice B
More information1. Theoretical background
1. Theoretical background We consider the energy budget at the soil surface (equation 1). Energy flux components absorbed or emitted by the soil surface are: net radiation, latent heat flux, sensible heat
More informationHeat Energy FORMS OF ENERGY LESSON PLAN 2.7. Public School System Teaching Standards Covered
FORMS OF ENERGY LESSON PLAN 2.7 Heat Energy This lesson is designed for 3rd 5th grade students in a variety of school settings (public, private, STEM schools, and home schools) in the seven states served
More informationIn today s world of wireless communications
TUTORIAL RF CERAMIC CHIP CAPACITORS IN HIGH RF POWER APPLICATIONS Reprinted with permission of MICROWAVE JOURNAL from the April 2000 issue. 2000 Horizon House Publications, Inc. In today s world of wireless
More informationModule 2.2. Heat transfer mechanisms
Module 2.2 Heat transfer mechanisms Learning Outcomes On successful completion of this module learners will be able to - Describe the 1 st and 2 nd laws of thermodynamics. - Describe heat transfer mechanisms.
More informationGreen Heating. Pupil Research Brief. Teachers Notes. Syllabus Coverage Subject Knowledge and Understanding. Route through the Brief UPIL ESEARCHER
R P UPIL ESEARCHER Green Heating I NITIATIVE Pupil Research Brief Teachers Notes Syllabus Coverage Subject Knowledge and Understanding all types of electromagnetic radiation form a continuous spectrum
More informationScience Standard 3 Energy and Its Effects Grade Level Expectations
Science Standard 3 Energy and Its Effects Grade Level Expectations Science Standard 3 Energy and Its Effects The flow of energy drives processes of change in all biological, chemical, physical, and geological
More informationHeat Transfer: Conduction, Convection, and Radiation
Heat Transfer: Conduction, Convection, and Radiation Introduction We have learned that heat is the energy that makes molecules move. Molecules with more heat energy move faster, and molecules with less
More informationInfrared and Its Application For Drying Coatings On Webs
Infrared and Its Application For Drying Coatings On Webs AIMCAL FALL TECHNICAL CONFERENCE 2005 By: Bob Narang Radiant Energy Systems, Inc. www.radiantenergy.com Water or solvent based wet coatings applied
More informationHow To Build A Solar Energised Power Plant
Project Title Solar Energised Power Plant Project Description In recent years energy crisis has become one of the most talked about issues around the world. Especially in the developing countries, the
More informationImpregnating Machine
Impregnating Machine Dasan Engineering manufactured Resin Coating & Laminating Machine for composite material and insulating material in addition to Impregnating & drying machine by means of high efficiency
More informationElectronics and Soldering Notes
Electronics and Soldering Notes The Tools You ll Need While there are literally one hundred tools for soldering, testing, and fixing electronic circuits, you only need a few to make robot. These tools
More informationTHERMAL RADIATION (THERM)
UNIVERSITY OF SURREY DEPARTMENT OF PHYSICS Level 2 Classical Laboratory Experiment THERMAL RADIATION (THERM) Objectives In this experiment you will explore the basic characteristics of thermal radiation,
More informationTopic Page Contents Page
Heat energy (11-16) Contents Topic Page Contents Page Heat energy and temperature 3 Latent heat energy 15 Interesting temperatures 4 Conduction of heat energy 16 A cooling curve 5 Convection 17 Expansion
More informationGeneral Thoughts on Generator Set - Acoustic Solutions & Noise Control
t: 023 81 290160 www.excelpowerltd.co.uk f: 023 81 290260 info@excelpowerltd.co.uk General Thoughts on Generator Set - Acoustic Solutions & Noise Control Written By Steve Delaney A.M.I.O.A. of TAS Ltd
More informationSteady Heat Conduction
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 how long
More informationUNIT 1 GCSE PHYSICS 1.1.1 Infrared Radiation 2011 FXA
1 All objects emit and absorb thermal radiation. The hotter an object is the infrared radiation it radiates in a given time. It is continually being transferred to and from all objects. The hotter the
More informationAfter a wave passes through a medium, how does the position of that medium compare to its original position?
Light Waves Test Question Bank Standard/Advanced Name: Question 1 (1 point) The electromagnetic waves with the highest frequencies are called A. radio waves. B. gamma rays. C. X-rays. D. visible light.
More informationOverview. What is EMR? Electromagnetic Radiation (EMR) LA502 Special Studies Remote Sensing
LA502 Special Studies Remote Sensing Electromagnetic Radiation (EMR) Dr. Ragab Khalil Department of Landscape Architecture Faculty of Environmental Design King AbdulAziz University Room 103 Overview What
More information(Walter Glogowski, Chaz Shapiro & Reid Sherman) INTRODUCTION
Convection (Walter Glogowski, Chaz Shapiro & Reid Sherman) INTRODUCTION You know from common experience that when there's a difference in temperature between two places close to each other, the temperatures
More informationSolar Flux and Flux Density. Lecture 3: Global Energy Cycle. Solar Energy Incident On the Earth. Solar Flux Density Reaching Earth
Lecture 3: Global Energy Cycle Solar Flux and Flux Density Planetary energy balance Greenhouse Effect Vertical energy balance Latitudinal energy balance Seasonal and diurnal cycles Solar Luminosity (L)
More informationThe First Law of Thermodynamics
The First aw of Thermodynamics Q and W are process (path)-dependent. (Q W) = E int is independent of the process. E int = E int,f E int,i = Q W (first law) Q: + heat into the system; heat lost from the
More informationSolar Energy. Outline. Solar radiation. What is light?-- Electromagnetic Radiation. Light - Electromagnetic wave spectrum. Electromagnetic Radiation
Outline MAE 493R/593V- Renewable Energy Devices Solar Energy Electromagnetic wave Solar spectrum Solar global radiation Solar thermal energy Solar thermal collectors Solar thermal power plants Photovoltaics
More informationEverline Module Application Note: Round LED Module Thermal Management
Everline Module Application Note: Round LED Module Thermal Management PURPOSE: Use of proper thermal management is a critical element of Light Emitting Diode (LED) system design. The LED temperature directly
More informationInfrared Moisture Detection
What it can do for you... what it can t and why 1. Infrared camera basics 2. Examples Lew Harriman MoistureDM.com 3. Summary - The 4 most important facts about infrared moisture detection 1 of 19 Infrared
More informationThe Ideal Gas Law. Gas Constant. Applications of the Gas law. P = ρ R T. Lecture 2: Atmospheric Thermodynamics
Lecture 2: Atmospheric Thermodynamics Ideal Gas Law (Equation of State) Hydrostatic Balance Heat and Temperature Conduction, Convection, Radiation Latent Heating Adiabatic Process Lapse Rate and Stability
More informationKinetic Theory. Energy. Transfers and Efficiency. The National Grid
AQA P1 Revision Infrared Radiation Heating and Insulating Buildings Kinetic Theory Energy Transfers and Efficiency Energy Transfer by Heating Transferring Electrical Energy Generating Electricity The National
More informationHEAT AND MASS TRANSFER
MEL242 HEAT AND MASS TRANSFER Prabal Talukdar Associate Professor Department of Mechanical Engineering g IIT Delhi prabal@mech.iitd.ac.in MECH/IITD Course Coordinator: Dr. Prabal Talukdar Room No: III,
More informationHeat Transfer and Energy
What is Heat? Heat Transfer and Energy Heat is Energy in Transit. Recall the First law from Thermodynamics. U = Q - W What did we mean by all the terms? What is U? What is Q? What is W? What is Heat Transfer?
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Sample Mid-Term 3 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) If you double the frequency of a vibrating object, its period A) is quartered.
More informationSOLAR ENERGY FUNDAMENTALS
Radiantec SOLAR ENERGY FUNDAMENTALS G E N E R A L S U P P L E M E N T 420 by Radiantec Company What is Solar Energy? What is the Sun? The sun is a star, not much different from the billions of others in
More informationBob Willis leadfreesoldering.com
Assembly of Flexible Circuits with Lead-Free Solder Alloy Bob Willis leadfreesoldering.com Introduction to Lead-Free Assembly Video Clips Component www.bobwillis.co.uk/lead/videos/components.rm Printed
More informationRadiation Transfer in Environmental Science
Radiation Transfer in Environmental Science with emphasis on aquatic and vegetation canopy media Autumn 2008 Prof. Emmanuel Boss, Dr. Eyal Rotenberg Introduction Radiation in Environmental sciences Most
More informationEnergy - Heat, Light, and Sound
Science Benchmark: 06:06 Heat, light, and sound are all forms of energy. Heat can be transferred by radiation, conduction and convection. Visible light can be produced, reflected, refracted, and separated
More informationApplication Note. Soldering Methods and Procedures for 1st and 2nd Generation Power Modules. Overview. Analysis of a Good Solder Joint
Soldering Methods and Procedures for 1st and 2nd Generation Power Modules Overview This document is intended to provide guidance in utilizing soldering practices to make high quality connections of Vicor
More information6 th Grade Science Assessment: Weather & Water Select the best answer on the answer sheet. Please do not make any marks on this test.
Select the be answer on the answer sheet. Please do not make any marks on this te. 1. Weather is be defined as the A. changes that occur in cloud formations from day to day. B. amount of rain or snow that
More informationRADIANT HEATING WITH INFRARED
W A T L O W RADIANT HEATING WITH INFRARED A TECHNICAL GUIDE TO UNDERSTANDING AND APPLYING INFRARED HEATERS ed Contents Topic Page The Advantages of Radiant Heat............................... 1 The Theory
More informationTHERMAL DESIGN AND TEST REQUIREMENTS FOR OUTSIDE PLANT CABLE TELECOMMUNICATIONS EQUIPMENT Al Marshall, P.E. Philips Broadband Networks
THERMAL DESIGN AND TEST REQUIREMENTS FOR OUTSIDE PLANT CABLE TELECOMMUNICATIONS EQUIPMENT Al Marshall, P.E. Philips Broadband Networks Abstract Shrinking thermal margins, driven by sophisticated but thermally
More informationSurface Mount Technology cooling for high volumes applications by: Cesare Capriz Aavid Thermalloy via XXV Aprile 32 Cadriano (BO) ITALY
Surface Mount Technology cooling for high volumes applications by: Cesare Capriz Aavid Thermalloy via XXV Aprile 32 Cadriano (BO) ITALY Abstract: The automotive technology is fast moving in integrating
More informationMAKING SENSE OF ENERGY Electromagnetic Waves
Adapted from State of Delaware TOE Unit MAKING SENSE OF ENERGY Electromagnetic Waves GOALS: In this Part of the unit you will Learn about electromagnetic waves, how they are grouped, and how each group
More informationLecture 7 Heat Transfer & Thermal Insulation. J. G. Weisend II
Lecture 7 Heat Transfer & Thermal Insulation J. G. Weisend II Goals Introduce conduction, convection & radiation heat transfer as they apply to cryogenics Describe design techniques to reduce heat transfer
More informationHumidity, Condensation, Clouds, and Fog. Water in the Atmosphere
Humidity, Condensation, Clouds, and Fog or Water in the Atmosphere The Hydrologic Cycle Where the Water Exists on Earth Evaporation From the Oceans and Land The Source of Water Vapor for the Atmosphere
More informationSeasonal & Daily Temperatures. Seasons & Sun's Distance. Solstice & Equinox. Seasons & Solar Intensity
Seasonal & Daily Temperatures Seasons & Sun's Distance The role of Earth's tilt, revolution, & rotation in causing spatial, seasonal, & daily temperature variations Please read Chapter 3 in Ahrens Figure
More informationTHERMAL ANALYSIS. Overview
W H I T E P A P E R THERMAL ANALYSIS Overview In this white paper we define and then outline the concept of thermal analysis as it relates to product design. We discuss the principles of conduction, convection,
More informationWhat is Energy? What is the relationship between energy and work?
What is Energy? What is the relationship between energy and work? Compare kinetic and potential energy What are the different types of energy? What is energy? Energy is the ability to do work. Great, but
More informationAn equivalent circuit of a loop antenna.
3.2.1. Circuit Modeling: Loop Impedance A loop antenna can be represented by a lumped circuit when its dimension is small with respect to a wavelength. In this representation, the circuit parameters (generally
More informationBasic Equations, Boundary Conditions and Dimensionless Parameters
Chapter 2 Basic Equations, Boundary Conditions and Dimensionless Parameters In the foregoing chapter, many basic concepts related to the present investigation and the associated literature survey were
More informationAssembly of LPCC Packages AN-0001
Assembly of LPCC Packages AN-0001 Surface Mount Assembly and Handling of ANADIGICS LPCC Packages 1.0 Overview ANADIGICS power amplifiers are typically packaged in a Leadless Plastic Chip Carrier (LPCC)
More informationWhat is surface mount?
A way of attaching electronic components to a printed circuit board The solder joint forms the mechanical and electrical connection What is surface mount? Bonding of the solder joint is to the surface
More informationPHYS 222 Spring 2012 Final Exam. Closed books, notes, etc. No electronic device except a calculator.
PHYS 222 Spring 2012 Final Exam Closed books, notes, etc. No electronic device except a calculator. NAME: (all questions with equal weight) 1. If the distance between two point charges is tripled, the
More informationTeaching Time: One-to-two 50-minute periods
Lesson Summary Students create a planet using a computer game and change features of the planet to increase or decrease the planet s temperature. Students will explore some of the same principles scientists
More informationInterested in conducting your own webinar? Email webinars@bnpmedia.com
Interested in conducting your own webinar? Email webinars@bnpmedia.com IR Applications in the Real World Archive www.process-heating.com Add to your favorites IR Applications in the Real World What it
More informationCFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER
International Journal of Advancements in Research & Technology, Volume 1, Issue2, July-2012 1 CFD SIMULATION OF SDHW STORAGE TANK WITH AND WITHOUT HEATER ABSTRACT (1) Mr. Mainak Bhaumik M.E. (Thermal Engg.)
More informationMCQ - ENERGY and CLIMATE
1 MCQ - ENERGY and CLIMATE 1. The volume of a given mass of water at a temperature of T 1 is V 1. The volume increases to V 2 at temperature T 2. The coefficient of volume expansion of water may be calculated
More informationElectromagnetic Radiation Energy that comes to us from the sun is transported in the form of waves known as electromagnetic energy.
Electromagnetic Radiation Energy that comes to us from the sun is transported in the form of waves known as electromagnetic energy. This combines electricity and magnetism such that setting up an electric
More informationThe photoionization detector (PID) utilizes ultraviolet
Chapter 6 Photoionization Detectors The photoionization detector (PID) utilizes ultraviolet light to ionize gas molecules, and is commonly employed in the detection of volatile organic compounds (VOCs).
More informationLecture 23: Terrestrial Worlds in Comparison. This lecture compares and contrasts the properties and evolution of the 5 main terrestrial bodies.
Lecture 23: Terrestrial Worlds in Comparison Astronomy 141 Winter 2012 This lecture compares and contrasts the properties and evolution of the 5 main terrestrial bodies. The small terrestrial planets have
More informationObjectives 200 CHAPTER 4 RESISTANCE
Objectives Explain the differences among conductors, insulators, and semiconductors. Define electrical resistance. Solve problems using resistance, voltage, and current. Describe a material that obeys
More information5 Things. You Must Know. Before Buying. Radiant Barrier
Consumer Report: 5 Things You Must Know Before Buying Radiant Barrier 1 INDEX I: How Do Radiant Barriers Really Work pg 3 A: Understanding Heat Transfer pg 3 B: How Radiant Barriers Stop the Heat pg 4
More informationimagine SOLAR AIR CONDITIONING MADE EASY
imagine SOLAR AIR CONDITIONING MADE EASY WHY SOLAR COOLING? Imagine...being able to fit a solar air conditioning system to your building that would result in dramatic reductions in electricity consumption
More informationPhysics PH1FP. (Jun15PH1FP01) General Certificate of Secondary Education Foundation Tier June 2015. Unit Physics P1. Unit Physics P1 TOTAL
Centre Number Surname Candidate Number For Examiner s Use Other Names Candidate Signature Examiner s Initials Question Mark Science A Unit Physics P1 Physics Unit Physics P1 Friday 12 June 2015 General
More informationGLOBAL COLLEGE OF ENGINEERING &TECHNOLOGY: YSR DIST. Unit VII Fiber Optics Engineering Physics
Introduction Fiber optics deals with the light propagation through thin glass fibers. Fiber optics plays an important role in the field of communication to transmit voice, television and digital data signals
More informationOverview of Baseboard Heating
Overview of Baseboard Heating If you live in an apartment equipped with a baseboard heating system, please take a moment to review the following sections so that you can better understand how your heating
More informationEnergy Pathways in Earth s Atmosphere
BRSP - 10 Page 1 Solar radiation reaching Earth s atmosphere includes a wide spectrum of wavelengths. In addition to visible light there is radiation of higher energy and shorter wavelength called ultraviolet
More informationGood Boards = Results
Section 2: Printed Circuit Board Fabrication & Solderability Good Boards = Results Board fabrication is one aspect of the electronics production industry that SMT assembly engineers often know little about.
More information