Physics Guide First Assessment 2016
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Radiant Heating with Infrared
W A T L O W RADIANT HEATING WITH INFRARED A TECHNICAL GUIDE TO UNDERSTANDING AND APPLYING INFRARED HEATERS Bleed Contents Topic Page The Advantages of Radiant Heat . 1 The Theory of Radiant Heat Transfer . 2 Problem Solving . 14 Controlling Radiant Heaters . 25 Tips On Oven Design . 29 Watlow RAYMAX® Heater Specifications . 34 The purpose of this technical guide is to assist customers in their oven design process, not to put Watlow in the position of designing (and guaranteeing) radiant ovens. The final responsibility for an oven design must remain with the equipment builder. This technical guide will provide you with an understanding of infrared radiant heating theory and application principles. It also contains examples and formulas used in determining specifications for a radiant heating application. To further understand electric heating principles, thermal system dynamics, infrared temperature sensing, temperature control and power control, the following information is also available from Watlow: • Watlow Product Catalog • Watlow Application Guide • Watlow Infrared Technical Guide to Understanding and Applying Infrared Temperature Sensors • Infrared Technical Letter #5-Emissivity Table • Radiant Technical Letter #11-Energy Uniformity of a Radiant Panel © Watlow Electric Manufacturing Company, 1997 The Advantages of Radiant Heat Electric radiant heat has many benefits over the alternative heating methods of conduction and convection: • Non-Contact Heating Radiant heaters have the ability to heat a product without physically contacting it. This can be advantageous when the product must be heated while in motion or when physical contact would contaminate or mar the product’s surface finish. • Fast Response Low thermal inertia of an infrared radiation heating system eliminates the need for long pre-heat cycles. -
Comparisons of Perceived Exertion of Elliptical Training Versus Treadmill
COMPARISONS OF PERCEIVED EXERTION ON ELLIPTICAL TRAINING VERSUS TREADMILL EXERCISE A Thesis Presented to the Faculty of the College of Education Morehead State University In Partial Fulfillment of the Requirements for the Degree Master of Arts by Marcisha Brazley July, 2002 Mf,IJ._ TIIEiS!S {,,( 3.11012.... B 'Z 'J..7 c. COMPARISONS OF PERCEIVED EXERTION ON ELLIPTICAL TRAINING VERSUS TREADMILL EXERCISE Marcisha Brazley, M.A. Morehead State University, 2002 Director of Thesis: --'--=----''---c=.---''-'---..,_,,-"--"-"'.=..c--"'~-Ao.,-.Q?,.j:!sr j;; ,,{, 0, Statement of the Problem: The relationship between rates of perceived exertion (RPE) during elliptical trainer exercise and treadmill exercise is undefined. Therefore, the purpose of this investigation was to compare and determine whether there are differences in RPE with respect to submaximal workloads between elliptical trainer exercise and treadmill exercise. Sources of d,ata: Five normotensive males, age 21 to 25 years (22.4 ± 1.7) and six normotensive females, age 20 to 23 years (21 ±1.2), VO2 max values 30-59 ml/min/kg were recruited from the Health, Physical Education, and Exercise Science classes at Morehead State University (M.S.U.) and the Wellness Center at Morehead State University. Methods: Each subject completed one graded exercise test on a treadmill as determined by a Bruce protocol. On a separate day, each subject completed one graded exercise test, as determined by a predetermined protocol, on a Precor® EFX544 elliptical cross trainer. The second test was conducted at least 48 hours after the first test. Rate of perceived exertion and heart rate values were recorded after every three minutes of each exercise session. -
A Compilation of Data on the Radiant Emissivity of Some Materials at High Temperatures
This is a repository copy of A compilation of data on the radiant emissivity of some materials at high temperatures. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/133266/ Version: Accepted Version Article: Jones, JM orcid.org/0000-0001-8687-9869, Mason, PE and Williams, A (2019) A compilation of data on the radiant emissivity of some materials at high temperatures. Journal of the Energy Institute, 92 (3). pp. 523-534. ISSN 1743-9671 https://doi.org/10.1016/j.joei.2018.04.006 © 2018 Energy Institute. Published by Elsevier Ltd. This is an author produced version of a paper published in Journal of the Energy Institute. Uploaded in accordance with the publisher's self-archiving policy. This manuscript version is made available under the Creative Commons CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ Reuse This article is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs (CC BY-NC-ND) licence. This licence only allows you to download this work and share it with others as long as you credit the authors, but you can’t change the article in any way or use it commercially. More information and the full terms of the licence here: https://creativecommons.org/licenses/ Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ A COMPILATION OF DATA ON THE RADIANT EMISSIVITY OF SOME MATERIALS AT HIGH TEMPERATURES J.M Jones, P E Mason and A. -
Energy and Training Module ITU Competitive Coach
37 energy and training module ITU Competitive Coach Produced by the International Triathlon Union, 2007 38 39 energy & training Have you ever wondered why some athletes shoot off the start line while others take a moment to react? Have you every experienced a “burning” sensation in your muscles on the bike? Have athletes ever claimed they could ‘keep going forever!’? All of these situations involve the use of energy in the body. Any activity the body performs requires work and work requires energy. A molecule called ATP (adenosine triphosphate) is the “energy currency” of the body. ATP powers most cellular processes that require energy including muscle contraction required for sport performance. Where does ATP come from and how is it used? ATP is produced by the breakdown of fuel molecules—carbohydrates, fats, and proteins. During physical activity, three different processes work to split ATP molecules, which release energy for muscles to use in contraction, force production, and ultimately sport performance. These processes, or “energy systems”, act as pathways for the production of energy in sport. The intensity and duration of physical activity determines which pathway acts as the dominant fuel source. Immediate energy system Fuel sources ATP Sport E.g. carbohydrates, energy performance proteins, fats “currency” Short term energy system E.g. swimming, cycling, running, transitions Long term energy system During what parts of a triathlon might athletes use powerful, short, bursts of speed? 1 2 What duration, intensity, and type of activities in a triathlon cause muscles to “burn”? When in a triathlon do athletes have to perform an action repeatedly for longer than 10 or 15 3 minutes at a moderate pace? 40 energy systems Long Term (Aerobic) System The long term system produces energy through aerobic (with oxygen) pathways. -
Energy Expenditure During Acute Weight Training Exercises in Healthy Participants: a Preliminary Study
applied sciences Article Energy Expenditure during Acute Weight Training Exercises in Healthy Participants: A Preliminary Study Muhammad Adeel 1,2, Chien-Hung Lai 3,4, Chun-Wei Wu 2, Jiunn-Horng Kang 3,4, Jian-Chiun Liou 2, Hung-Chou Chen 3,5 , Meng-Jyun Hong 2 and Chih-Wei Peng 1,2,6,* 1 International PhD Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei 110, Taiwan; [email protected] 2 School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei 110, Taiwan; [email protected] (C.-W.W.); [email protected] (J.-C.L.); [email protected] (M.-J.H.) 3 Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan; [email protected] (C.-H.L.); [email protected] (J.-H.K.); [email protected] (H.-C.C.) 4 Department of Physical Medicine and Rehabilitation, Taipei Medical University Hospital, Taipei 110, Taiwan 5 Department of Physical Medicine and Rehabilitation, Shuang Ho Hospital, Taipei Medical University, New Taipei City 235, Taiwan 6 School of Gerontology Health Management, College of Nursing, Taipei Medical University, Taipei 110, Taiwan * Correspondence: [email protected]; Tel./Fax: +886-2-2736-1661 (ext. 3070) Abstract: Energy expenditure during weight training exercises produces great fitness and health benefits for humans, but few studies have investigated energy expenditure directly during weight training. Therefore, in this study, we aimed to determine energy costs during three training sessions Citation: Adeel, M.; Lai, C.-H.; Wu, consisting of three different exercises. -
Black Body Radiation and Radiometric Parameters
Black Body Radiation and Radiometric Parameters: All materials absorb and emit radiation to some extent. A blackbody is an idealization of how materials emit and absorb radiation. It can be used as a reference for real source properties. An ideal blackbody absorbs all incident radiation and does not reflect. This is true at all wavelengths and angles of incidence. Thermodynamic principals dictates that the BB must also radiate at all ’s and angles. The basic properties of a BB can be summarized as: 1. Perfect absorber/emitter at all ’s and angles of emission/incidence. Cavity BB 2. The total radiant energy emitted is only a function of the BB temperature. 3. Emits the maximum possible radiant energy from a body at a given temperature. 4. The BB radiation field does not depend on the shape of the cavity. The radiation field must be homogeneous and isotropic. T If the radiation going from a BB of one shape to another (both at the same T) were different it would cause a cooling or heating of one or the other cavity. This would violate the 1st Law of Thermodynamics. T T A B Radiometric Parameters: 1. Solid Angle dA d r 2 where dA is the surface area of a segment of a sphere surrounding a point. r d A r is the distance from the point on the source to the sphere. The solid angle looks like a cone with a spherical cap. z r d r r sind y r sin x An element of area of a sphere 2 dA rsin d d Therefore dd sin d The full solid angle surrounding a point source is: 2 dd sind 00 2cos 0 4 Or integrating to other angles < : 21cos The unit of solid angle is steradian. -
CNT-Based Solar Thermal Coatings: Absorptance Vs. Emittance
coatings Article CNT-Based Solar Thermal Coatings: Absorptance vs. Emittance Yelena Vinetsky, Jyothi Jambu, Daniel Mandler * and Shlomo Magdassi * Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; [email protected] (Y.V.); [email protected] (J.J.) * Correspondence: [email protected] (D.M.); [email protected] (S.M.) Received: 15 October 2020; Accepted: 13 November 2020; Published: 17 November 2020 Abstract: A novel approach for fabricating selective absorbing coatings based on carbon nanotubes (CNTs) for mid-temperature solar–thermal application is presented. The developed formulations are dispersions of CNTs in water or solvents. Being coated on stainless steel (SS) by spraying, these formulations provide good characteristics of solar absorptance. The effect of CNT concentration and the type of the binder and its ratios to the CNT were investigated. Coatings based on water dispersions give higher adsorption, but solvent-based coatings enable achieving lower emittance. Interestingly, the binder was found to be responsible for the high emittance, yet, it is essential for obtaining good adhesion to the SS substrate. The best performance of the coatings requires adjusting the concentration of the CNTs and their ratio to the binder to obtain the highest absorptance with excellent adhesion; high absorptance is obtained at high CNT concentration, while good adhesion requires a minimum ratio between the binder/CNT; however, increasing the binder concentration increases the emissivity. The best coatings have an absorptance of ca. 90% with an emittance of ca. 0.3 and excellent adhesion to stainless steel. Keywords: carbon nanotubes (CNTs); binder; dispersion; solar thermal coating; absorptance; emittance; adhesion; selectivity 1. -
Radiation Exchange Between Surfaces
Chapter 1 Radiation Exchange Between Surfaces 1.1 Motivation and Objectives Thermal radiation, as you know, constitutes one of the three basic modes (or mechanisms) of heat transfer, i.e., conduction, convection, and radiation. Actually, on a physical basis, there are only two mechanisms of heat transfer; diffusion (the transfer of heat via molecular interactions) and radiation (the transfer of heat via photons/electomagnetic waves). Convection, being the bulk transport of a fluid, is not precisely a heat transfer mechanism. The physics of radiation transport are distinctly different than diffusion transport. The latter is a local phenomena, meaning that the rate of diffusion heat transfer, at a point in space, precisely depends only on the local nature about the point, i.e., the temperature gradient and thermal conductivity at the point. Of course, the temperature field will depend on the boundary and initial conditions imposed on the system. However, the diffusion heat flux at, say, one point in the system does not directly effect the diffusion flux at some distant point. Radiation, on the other hand, is not local; the flux of radiation at a point will, in general, be directly and instantaneously dependent on the radiation flux at all points in a system. Unlike diffusion, radiation can act over a distance. Accordingly, the mathematical description of radiation transport will employ an integral equation for the radiation field, as opposed to the differential equation for heat diffusion. Our objectives in studying radiation in the short amount of time left in the course will be to 1. Develop a basic physical understanding of electromagnetic radiation, with emphasis on the properties of radiation that are relevant to heat transfer. -
The Effects of Motion on Trunk Biomechanics
Clinical Biomechanics 15 (2000) 703±717 www.elsevier.com/locate/clinbiomech Review paper The eects of motion on trunk biomechanics K.G. Davis, W.S. Marras * Biodynamics Laboratory, Room 210, 210 Baker Systems, 1971 Neil Avenue, The Ohio State University, Columbus, OH 43210, USA Received 15 June 2000; accepted 16 June 2000 Abstract Objective. To review the literature that evaluates the in¯uence of trunk motion on trunk strength and structural loading. Background. In recent years, trunk dynamics have been identi®ed as potential risk factors for developing low-back disorders. Consequently, a better understanding of the underlying mechanisms involved in trunk motion is needed. Methods. This review summarizes the results of 53 studies that have evaluated trunk motion and its impact on several biome- chanical outcome measures. The biomechanical measures consisted of trunk strength, intra-abdominal pressure, muscle activity, imposed trunk moments, and spinal loads. Each of these biomechanical measures was discussed in relation to the existing knowledge within each plane of motion (extension, ¯exion, lateral ¯exion, twisting, and asymmetric extension). Results. Trunk strength was drastically reduced as dynamic motion increased, and males were impacted more than females. Intra- abdominal pressure seemed to only be aected by trunk dynamics at high levels of force. Trunk moments were found to increase monotonically with increased trunk motion. Both agonistic and antagonistic muscle activities were greater as dynamic character- istics increased. As a result, the three-dimensional spinal loads increase signi®cantly for dynamic exertions as compared to isometric conditions. Conclusions. Trunk motion has a dramatic aect on the muscle coactivity, which seems to be the underlying source for the decrease strength capability as well as the increased muscle force, IAP, and spinal loads. -
Fundamentals of Biomechanics Duane Knudson
Fundamentals of Biomechanics Duane Knudson Fundamentals of Biomechanics Second Edition Duane Knudson Department of Kinesiology California State University at Chico First & Normal Street Chico, CA 95929-0330 USA [email protected] Library of Congress Control Number: 2007925371 ISBN 978-0-387-49311-4 e-ISBN 978-0-387-49312-1 Printed on acid-free paper. © 2007 Springer Science+Business Media, LLC All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. 987654321 springer.com Contents Preface ix NINE FUNDAMENTALS OF BIOMECHANICS 29 Principles and Laws 29 Acknowledgments xi Nine Principles for Application of Biomechanics 30 QUALITATIVE ANALYSIS 35 PART I SUMMARY 36 INTRODUCTION REVIEW QUESTIONS 36 CHAPTER 1 KEY TERMS 37 INTRODUCTION TO BIOMECHANICS SUGGESTED READING 37 OF UMAN OVEMENT H M WEB LINKS 37 WHAT IS BIOMECHANICS?3 PART II WHY STUDY BIOMECHANICS?5 BIOLOGICAL/STRUCTURAL BASES -
Technological Advances to Maximize Solar Collector Energy Output
Swapnil S. Salvi School of Mechanical, Materials and Energy Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India Technological Advances to Vishal Bhalla1 School of Mechanical, Maximize Solar Collector Energy Materials and Energy Engineering, Indian Institute of Technology Ropar, Rupnagar 140001, Punjab, India Output: A Review Robert A. Taylor Since it is highly correlated with quality of life, the demand for energy continues to School of Mechanical and increase as the global population grows and modernizes. Although there has been signifi- Manufacturing Engineering; cant impetus to move away from reliance on fossil fuels for decades (e.g., localized pollu- School of Photovoltaics and tion and climate change), solar energy has only recently taken on a non-negligible role Renewable Energy Engineering, in the global production of energy. The photovoltaics (PV) industry has many of the same The University of New South Wales, electronics packaging challenges as the semiconductor industry, because in both cases, Sydney 2052, Australia high temperatures lead to lowering of the system performance. Also, there are several technologies, which can harvest solar energy solely as heat. Advances in these technolo- Vikrant Khullar gies (e.g., solar selective coatings, design optimizations, and improvement in materials) Mechanical Engineering Department, have also kept the solar thermal market growing in recent years (albeit not nearly as rap- Thapar University, idly as PV). This paper presents a review on how heat is managed in solar thermal and Patiala 147004, Punjab, India PV systems, with a focus on the recent developments for technologies, which can harvest heat to meet global energy demands. It also briefs about possible ways to resolve the Todd P. -
Emissivity – the Crux of Accurate Radiometric Measurement
EMISSIVITY – THE CRUX OF ACCURATE RADIOMETRIC MEASUREMENT Frank Liebmann Fluke Corporation Hart Scientific Division 799 Utah Valley Drive American Fork, UT 84003 801-763-1600 [email protected] Abstract - Infrared (IR) radiometry is a very useful form of temperature measurement. Its advantages over contact thermometry are that it has quick response times and it does not have to come in contact with the area being measured. One of its major drawbacks is that it not as accurate as contact thermometry. One of the major sources of this uncertainty is the emissivity of the surface being measured. This is true for calibration of these devices as well. The best way to calibrate an IR thermometer is by use of a near perfect blackbody. However, a near perfect blackbody is not always a practical option for calibration. Flat plates are needed for calibration of some IR thermometers. Emissivity is not always well behaved. Emissivity can vary with time, meaning that a flat plate’s surface coating needs to have a burn in time established. Emissivity can also vary with wavelength and temperature. This paper discusses the sources of error for flat plate emissivity. Knowledge of these sources leads to a more accurate calibration of IR thermometers. WHAT IS EMISSIVITY Emissivity is a material's ability to radiate as a perfect blackbody. It is a ratio or percentage of power a perfect blackbody would radiate at a given temperature. Every material radiates energy. The amount of radiated power is dependent on the material’s temperature and the material’s emissivity. IR thermometers take advantage of this.