Measurement of Temperature
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MODULE 11: GLOSSARY and CONVERSIONS Cell Engines
Hydrogen Fuel MODULE 11: GLOSSARY AND CONVERSIONS Cell Engines CONTENTS 11.1 GLOSSARY.......................................................................................................... 11-1 11.2 MEASUREMENT SYSTEMS .................................................................................. 11-31 11.3 CONVERSION TABLE .......................................................................................... 11-33 Hydrogen Fuel Cell Engines and Related Technologies: Rev 0, December 2001 Hydrogen Fuel MODULE 11: GLOSSARY AND CONVERSIONS Cell Engines OBJECTIVES This module is for reference only. Hydrogen Fuel Cell Engines and Related Technologies: Rev 0, December 2001 PAGE 11-1 Hydrogen Fuel Cell Engines MODULE 11: GLOSSARY AND CONVERSIONS 11.1 Glossary This glossary covers words, phrases, and acronyms that are used with fuel cell engines and hydrogen fueled vehicles. Some words may have different meanings when used in other contexts. There are variations in the use of periods and capitalization for abbrevia- tions, acronyms and standard measures. The terms in this glossary are pre- sented without periods. ABNORMAL COMBUSTION – Combustion in which knock, pre-ignition, run- on or surface ignition occurs; combustion that does not proceed in the nor- mal way (where the flame front is initiated by the spark and proceeds throughout the combustion chamber smoothly and without detonation). ABSOLUTE PRESSURE – Pressure shown on the pressure gauge plus at- mospheric pressure (psia). At sea level atmospheric pressure is 14.7 psia. Use absolute pressure in compressor calculations and when using the ideal gas law. See also psi and psig. ABSOLUTE TEMPERATURE – Temperature scale with absolute zero as the zero of the scale. In standard, the absolute temperature is the temperature in ºF plus 460, or in metric it is the temperature in ºC plus 273. Absolute zero is referred to as Rankine or r, and in metric as Kelvin or K. -
The Kelvin and Temperature Measurements
Volume 106, Number 1, January–February 2001 Journal of Research of the National Institute of Standards and Technology [J. Res. Natl. Inst. Stand. Technol. 106, 105–149 (2001)] The Kelvin and Temperature Measurements Volume 106 Number 1 January–February 2001 B. W. Mangum, G. T. Furukawa, The International Temperature Scale of are available to the thermometry commu- K. G. Kreider, C. W. Meyer, D. C. 1990 (ITS-90) is defined from 0.65 K nity are described. Part II of the paper Ripple, G. F. Strouse, W. L. Tew, upwards to the highest temperature measur- describes the realization of temperature able by spectral radiation thermometry, above 1234.93 K for which the ITS-90 is M. R. Moldover, B. Carol Johnson, the radiation thermometry being based on defined in terms of the calibration of spec- H. W. Yoon, C. E. Gibson, and the Planck radiation law. When it was troradiometers using reference blackbody R. D. Saunders developed, the ITS-90 represented thermo- sources that are at the temperature of the dynamic temperatures as closely as pos- equilibrium liquid-solid phase transition National Institute of Standards and sible. Part I of this paper describes the real- of pure silver, gold, or copper. The realiza- Technology, ization of contact thermometry up to tion of temperature from absolute spec- 1234.93 K, the temperature range in which tral or total radiometry over the tempera- Gaithersburg, MD 20899-0001 the ITS-90 is defined in terms of calibra- ture range from about 60 K to 3000 K is [email protected] tion of thermometers at 15 fixed points and also described. -
What Is Temperature
City Research Online City, University of London Institutional Repository Citation: Kyriacou, P. A. (2010). Temperature sensor technology. In: Jones, D. P. (Ed.), Biomedical Sensors. (pp. 1-38). New York: Momentum Press. ISBN 9781606500569 This is the accepted version of the paper. This version of the publication may differ from the final published version. Permanent repository link: https://openaccess.city.ac.uk/id/eprint/3539/ Link to published version: Copyright: City Research Online aims to make research outputs of City, University of London available to a wider audience. Copyright and Moral Rights remain with the author(s) and/or copyright holders. URLs from City Research Online may be freely distributed and linked to. Reuse: Copies of full items can be used for personal research or study, educational, or not-for-profit purposes without prior permission or charge. Provided that the authors, title and full bibliographic details are credited, a hyperlink and/or URL is given for the original metadata page and the content is not changed in any way. City Research Online: http://openaccess.city.ac.uk/ [email protected] Biomedical Sensors: Temperature Sensor Technology P A Kyriacou, PhD Reader in Biomedical Engineering School of Engineering and Mathematical Sciences City University, London EC1V 0HB “...the clinical thermometer ranks in importance with the stethoscope. A doctor without his thermometer is like a sailor without his compass” Family Physician, 1882 Celsius thermometer (attached to a barometer) made by J.G. Hasselström, Stockholm, late 18th century Page 1 of 39 1. Introduction Human body temperature is of vital importance to the well being of the person and therefore it is routinely monitored to indicate the state of the person’s health. -
Thermometry (Temperature Measurement)
THERMOMETRY Thermometry ................................................................................................................................................. 1 Applications .............................................................................................................................................. 2 Temperature metrology ............................................................................................................................. 2 The primary standard: the TPW-cell ..................................................................................................... 5 Temperature and the ITS-90 ..................................................................................................................... 6 The Celsius scale ................................................................................................................................... 6 Thermometers and thermal baths .......................................................................................................... 7 Metrological properties ............................................................................................................................. 7 Types of thermometers.............................................................................................................................. 9 Liquid-in-glass ...................................................................................................................................... 9 Thermocouple .................................................................................................................................... -
TEMPERATURE © 2019, 2008, 2004, 1990 by David A
TEMPERATURE © 2019, 2008, 2004, 1990 by David A. Katz. All rights reserved. A BRIEF HISTORY OF TEMPERATURE MEASUREMENT Ancient people were physically aware of hot and cold and probably related temperature by the size of the fire needed, and how close to sit, to keep warm. An Australian tribe, still primitive, uses dogs instead of blankets to keep warm, thus, they can relate temperature by the dog. (See Figure 1.) A moderately cool night may require two dogs to keep warm, thus it is a two-dog night. An icy night would be a six-dog night. Early people were, at first, fire tenders, maintaining fires originally Figure 1. Australian started by natural causes. Later, they learned how to make fire and aborginies use dogs became fire makers. Eventually, they became fire managers as they to keep warm. learned to work with fire to gain the heat needed to boil water, cook meat, fire pottery (500°F or 257°C), work with copper, tin, bronze (an alloy of copper and tin) and iron, and to make glass. (See Figure 2) Although they had no quantitative measuring devices to determine how hot a fire was, they developed recipes for building different types of fires and probably used a physical indicator, such as some mineral or metal melting, to indicate the correct Figure 2. Early people temperature for a particular process. used fire to cook food and later to work with The ancient Greeks knew that air expanded when heated and metals. applied the principle mechanically, but they developed no means of measuring temperature or amount of heat needed and devised no measuring instruments. -
The Science Behind Meaningful Temperature Measurement, Part 1: Introduction
Calibrating Thermometers: The Science Behind Meaningful Temperature Measurement, Part 1: Introduction By Maria Knake, Laboratory Assessment Program Manager Posted: May 2012 A Promise is a Promise I've said it myself: without calibration, we have no confidence in the measurements that we take. And if a measurement isn’t meaningful, why even bother? Nevertheless, if you’ve read my previous articles, "The Anatomy of a Liquid-in-Glass Thermometer" and "Let’s Get Digital," you know that, up to this point, I have (intentionally) avoided the subject of thermometer calibration. So, if calibration is such an important subject, why have I been avoiding it for so long? The answer is simple: I’ve been procrastinating. As I promised at the end of my last article, it’s time to finally talk about thermometer calibration, or what I like to call “the science behind meaningful temperature measurement.” If the cornerstone of any good measurement is calibration, then the cornerstone of any good calibration is the method(s) used to complete the calibration. Over my next few posts, I will explain some of the details of thermometer calibration. Units of Temperature Throughout history, many units and scales of temperature measurement have been developed for various applications around the world. In fact, historical accounts claim that over 35 different temperature scales had been developed by the 18th century. One of the most famous scales was developed by Daniel Gabriel Fahrenheit around 1714. Fahrenheit was the first scientist to use mercury in a liquid-in-glass thermometer. He used three fixed points to create his temperature scale. -
Lesson 1 the Nature and History of Temperature
Lektion 1 Sidan 2 av 5 © Pentronic AB 2017-01-19 ---------------------------------------------------------------------------------------------------------------------------------------------------- However, the thermometer had no real practical use until 1714, when the German physicist Daniel Gabriel Fahrenheit developed a temperature scale that made it possible to take comparative measurements. He is also considered to be the inventor of the mercury thermometer as it is today – that is, mercury inside a closed glass tube. It is worth pointing out that the glass thermometers containing mercury that may still be in use are being used by special exemption. Mercury is a stable substance but it becomes dangerous out in the environment. Today we use other liquids such as coloured alcohol. The temperature scales Fahrenheit Fahrenheit created a 100-degree scale in which zero degrees was the temperature of a mixture of sal ammoniac and snow – the coldest he could achieve in his laboratory in Danzig. As the upper fixed point he used the internal body temperature of a healthy human being and gave it the value of 100°F. In degrees Celsius this scale corresponds approximately to the range of -18 to +37 degrees. With this issue Pentronic begins its training in Becausetemperature it can be awkwardmeasurement to achieve .the We upper will fixed start point , he apparently introduced the more practical fixed points of +32°F and +96°F, which were respectively the freezing point of lesson 1 with a historical review and then continuewater and with the temperaturethermodynamics, of a human being’sheat armpittransfer. and quality assurance with calibration. Only after that will we move on to temperature sensors – primarily thermocouples and Pt100s.Fahrenheit’s scale was later extended to the boiling point of water, which was assigned the temperature value of +212°F. -
Thermodynamic Temperature
Thermodynamic temperature Thermodynamic temperature is the absolute measure 1 Overview of temperature and is one of the principal parameters of thermodynamics. Temperature is a measure of the random submicroscopic Thermodynamic temperature is defined by the third law motions and vibrations of the particle constituents of of thermodynamics in which the theoretically lowest tem- matter. These motions comprise the internal energy of perature is the null or zero point. At this point, absolute a substance. More specifically, the thermodynamic tem- zero, the particle constituents of matter have minimal perature of any bulk quantity of matter is the measure motion and can become no colder.[1][2] In the quantum- of the average kinetic energy per classical (i.e., non- mechanical description, matter at absolute zero is in its quantum) degree of freedom of its constituent particles. ground state, which is its state of lowest energy. Thermo- “Translational motions” are almost always in the classical dynamic temperature is often also called absolute tem- regime. Translational motions are ordinary, whole-body perature, for two reasons: one, proposed by Kelvin, that movements in three-dimensional space in which particles it does not depend on the properties of a particular mate- move about and exchange energy in collisions. Figure 1 rial; two that it refers to an absolute zero according to the below shows translational motion in gases; Figure 4 be- properties of the ideal gas. low shows translational motion in solids. Thermodynamic temperature’s null point, absolute zero, is the temperature The International System of Units specifies a particular at which the particle constituents of matter are as close as scale for thermodynamic temperature. -
Temperature Measurement Temperature Scales TH TC QC QH W
MAE 334 - INTRODUCTION TO COMPUTERS AND INSTRUMENTATION Temperature Measurement Gabriel Daniel Fahrenheit developed the mercury thermometer in 1714. Mercury has the desirable property of a low freezing point (-38.7 C), a high boiling point (357 C) and a relatively constant coefficient of thermal expansion. Being highly toxic, expensive, slow to respond and impractical to interface with a computer are significant issues preventing its wide spread use. Fahrenheit used a mixture of ice, salt and water as the zero degree reference point and the temperature of the human body as a 96 degree reference point. Anders Celsius created his temperature scale in 1742. Originally zero degrees was the boiling point of water and 100 degrees was the freezing point. These points were later reversed. Temperature Scales As described above original temperature scales were based on certain fixed points. A more rational definition is one based on the Second Law of Thermodynamics. The efficiency of a Carnot engine, , provides a definition of the zero point and a conceptual way of defining intermediate temperatures. W TQCC 11 QTQHHH QH QC TH TC W Figure 1. Carnot engine diagram - where heat flows from a high temperture TH furnace through the fluid of the "working body" (working substance) and into the cold sink TC, thus forcing the working substance to do mechanical work W on the surroundings, via cycles of contractions and expansions. The size of a degree based on the two common scales, Rankine (Fahrenheit) and Kelvin (Celsius), is described above. The Rankine and Kelvin scale are thermodynamic scales and can therefore be used in equations such as the ideal PV gas equation of state. -
MEASURING TEMPERATURE the Thermometer
MEASURING TEMPERATURE The Thermometer emperature — distinguishing between “the degree of hotness or coldness [of] a body or Tenvironment” (askoxford.com, 2005) — is a phenomenon that has been extensively investigated MIRVETTE CHAMOUN looks over a significant period of time. As a result of this investigation, a device known as the thermometer was at the historical development developed with a sole purpose of measuring the degree of hotness or coldness in a body or environ- of a measurement scale with ment using a particular scale (World Book, 2000). The apparatus constructed has the ability to show the the view of helping children temperature measure, as incorporated within its struc- ture is a liquid that rises and falls in a tube as the understand the role that temperature around it cools or warms (U Learn Today, 2001). This rise and fall is due to the fact that “when mathematics plays in society. the temperature rises, the liquid in the glass tube warms up and molecules move apart causing expan- sion in the liquid, which in turn takes up more space in the tube” (U Learn Today, 2001, p. 6). The history of the thermometer The thermometer took on many different shapes and forms over many years of exploration to get to where it is today. The accuracy and precision of the modern day thermometer came about after many years of trial and tribulation, experienced by an array of inventors and scientists. These scientists and inventors aimed in developing a device that took on the forces of the world around them to measure temperature. -
1. Temperature and the Ideal Gas Law (Note: This Is a Fairly Long Experiment
Physics 341 Chapter 1 Page 1-1 1. Temperature and the Ideal Gas Law (Note: This is a fairly long experiment. To save time, much of the graphing can be done “at home”. As always, make sure that you have all the data you need before you leave.) 1.1 Introduction The most important concept at the foundation of thermodynamics is that of thermal equilibrium. We take this for granted in our daily experiences. We know, for instance, that an ice cube will melt when taken out of the freezer – no matter what object “at room temperature” it is brought into contact with. This is the essence of the utility of temperature and thermal equilibrium: the direction of heat flow is independent of the substance involved - it depends on only temperature. In fact, this defines temperature. More precise observations of thermal equilibrium are as follows. First of all, as with the equally familiar notion of mechanical equilibrium, we may say that an isolated macroscopic system is in thermal equilibrium, or thermodynamic equilibrium, whenever it attains a state that is not observed to change with time, at least at a macroscopic level. Obviously, for such a situation to occur, it is also necessary that the system in question is in (internal) mechanical and chemical equilibrium. At the foundations of thermodynamics is the experimental fact that two systems in thermal equilibrium with a third system must also be in thermal equilibrium with each other. This is often referred to as the zeroth law of thermodynamics. It is what leads to the empirical notion of a temperature scale. -
Class – 9 Chemistry
Class – 9 Chemistry The common unit of Temperature :- The common unit of measuring temperature is degree Celsius which is written in short form as°C. There is another scale of temperature called Kelvin scale of temperature the SI unit of measuring temperature is Kelvin it is denoted by the symbol K . 0°C = 273 K The relation between Kelvin scale and Celsius scale of temperature can be written as Temperature of Kelvin scale = Temperature of Celsius scale+273 Example 1. convert the temperature of 25 °Cto the Kelvin scale. Solution :- Temperature on Kelvin scale = Temperature on Celsius scale + 273 =25+273 =298K Thus a temperature of 25 degree Celsius on Celsius scale is equal to 298 Kelvin on the Kelvin scale. Example 2 . Convert the temperature of 300 Kelvin to the Celsius scale. Solution. we know that temperature on Kelvin scale =Temperature on Celsius scale + 273 so , 300 = temperature on Celsius scale + 273 and , temperature on Celsius scale = 300 – 273 =27 degree Celsius Thus a temperature of 300 Kelvin on Kelvin scale is equal to 27 degree Celsius on Celsius scale. Note. It is clear from the above discussion that: 1. To convert a temperature on Celsius scale to the Kelvin scale we have to add 273 to the Celsius temperature. 2. and the convert a temperature on Kelvin scale to the Celsius scale we have to subtract 273 from the Kelvin temperature. Temperature is measured in Fahrenheit also. People in USA used the Fahrenheit degree while Indians use the Celsius degree. So we need to find out the exact temperature on means, if he says that he is at 100° F.