DOCSLIB.ORG

LATENT HEAT TRANSPORT and MICROLAYER EVAPORATION in NUCLEATE BOILING H H Jawurek

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
LATENT HEAT TRANSPORT and MICROLAYER EVAPORATION in NUCLEATE BOILING H H Jawurek LATENT HEAT TRANSPORT AND MICROLAYER EVAPORATION IN NUCLEATE BOILING H H Jawurek UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG SCHOOL OF MECHANICAL ENGINEERING LATENT HEAT TRANSPORT AND MICROLAYER EVAPORATION IN NUCLEATE BOILING H H JAWUREK A Thesis Presented in Fulfilment of the Requirements for the Degree of Doctor of Philosophy- August 1977 (ü) DECLARATION BY CANDIDATE I, Harald Hans Jawurek hereby declare that this thesis is my own work and that the material presented herein has not been submitted for any degree at any other university. (iü) ABSTRACT Part 1 of this work provides a broad overview and, where possible, a quantitative assessment of the complex physical processes which together constitute the mechanism of nucleate boiling heat transfer. It is shown that under a wide range of conditions the primary surface-to-liquid heat flows within an area of bubble influence are so redistributed as to manifest themselves predominantly as latent heat transport, that is, as vaporisation into attached bubbles. This and related findings are applied in the derivation of a new pool boiling heat transfer correlation. The correla- tion allows the prediction of boiling curves (q/A versus AT) at any pressure provided that one boiling curve for the same surface-liquid combination is. available as a reference. Part 2 deals in greater detail with one of the component processes of latent heat transport, namely microlayer evapora- tion. A literature review reveals the need for synchronised records of microlayer geometry versus time and of normal bubble growth and departure. An apparatus developed to pro- vide such records is described. High-speed cine interference photography from beneath and through a transparent heating surface provided details of microlayer geometry and an image- reflection system synchronised these records with the bubble profile views. Results are given for methanol and ethanol boiling at sub-atmospheric pressures and at various heat fluxes and bulk subcoolings. In all cases it is found that microlayers were of sub-micron thickness, that microlayer thinning was restricted to the inner layer edge (with the thickness elsewhere remaining constant or increasing with time) and that the contribution of this visible evaporation to the total vapour flow into bubbles was negligible. The observa- tion of thickening towards the outer microlayer edge, however, demonstrates that a liquid replenishment flow occurred simul- taneously with the evaporation process. The effects of such replenishment are investigated by means of a numerical analysis of microlayer heat transfer. The analysis indicates that the net evaporation from the continuously re- plenished microlayers was a significant contributor to the total bubble growth. The optical results of the present study are thus reconciled with the deductions of published surface- thermometry studies. The forces acting on the observed bubbles are analysed and are found to be compatible with a replenishment mechanism. Microlayer interferometry studies founded on published portions of the present study are discussed and controversial results analysed. Civ) ACKNOWLEDGEMENTS Numerous colleagues, friends and teachers, my employers and members of my family have contributed to this work. I am deeply indebted and grateful to them all. In particular, I offer my warm thanks to Professor C J Rallis for his enthusiasm, advice and encouragement and to Dr W L Grant and the Atomic Energy Board for the approval and funding of this project and of my scholar- ship. I should like to thank Dr G E B Tremeer, Professor A M Starfield and Mr G F de Vries for their help with computing problems, Dr J H Talbot for clarifying certain aspects of laser optics, and Mr D J Maritz for assistance with experimentation and photography. Dr J J Wannenburg made available printing and draughting facilities, Mrs Daphne Germond typed the manuscript with patience and accuracy and Mrs Lana Botes prepared the figures meticulously; i am most grateful to them. Finally my thanks go to my wife, who through her encourage- ment and active involvement contributed greatly to the completion of this study. (v) CONTENTS PACE DECLARATION (ii) ABSTRACT (iii) ACKNOWLEDGEMENTS (iv) CONTENTS (v) LIST OF FIGURES (xii) LIST OF TABLES (xix") NOMENCLATURE (xxil CHAPTER 1 INTRODUCTION 1 1.1 BACKGROUND AND HISTORY OF THESIS 1 1.2 STRUCTURE AND OUTLINE OF THESIS 5 1 .3 UNITS 5 PART 1 LATENT HEAT TRANSPORT 7 CHAPTER 2 THE MECHANISM OF SATURATED POOL BOILING: AN INTERPRETIVE REVIEW 8 2.1 INTRODUCTION 8 2.1.1 Aims and Scope 8 2.1.2 Presentation and Method 9 2.2 INSIGNIFICANT LATENT HEAT TRANSPORT. MICROCONVECTION 10 2.2.1 Early Heat Transfer Correlations Based on Microconvection 20 2.3 FURTHER PROPOSALS ON BUBBLE-INDUCED CONVECTION 23 2.3.1 Area of Bubble Influence 26 2.3.2 The Bulk Convection Mechanism of Ilan and Griffith 29 2.3.3 Thermal Laver Recoverv bv Convection 34 The Bulk Convection Correlation of Mikic and Rohsenow 34 (vi) PAGE 2.4 EXPERIMENTAL STUDIES ON BUBBLE-INDUCED 38 CONVECTION 2.4.1 Optical Studies 39 2.4.2 Microthennometry Studies 42 2.4.3 Interim Conclusions 45 2.5 BREAKDOWN OF HEAT FLOW IN AREA OF BUBBLE INFLUENCE 46 2.5.1 Summary of Foregoing Sections in Terms of New Nomenclature 50 2.6 LATENT HEAT TRANSPORT 51 2.6.1 First Measurements of (q/A)L„; Rallis et al 52 2.6.2 First Evidence of Microlayer Effects; Moore and Mesler 55 2.6.3 Indirect Evidence of Significant Latent Heat Transport in Subcooled Boiling 57 2.6.4 Bubble Coalescence and Latent Heat Transport Estimates in Saturated Boiling 61 2.6.5 Measurements of Rallis and Jawurek; Water Boiling from Thin Wire 67 2.6.6 Measurement." of Novakovic et al; Bthanol Boiling on Mercury Surface 72 2.6.7 Measurements of van Strålen; Water Boiling from Thin Wire 77 2.6.8 Measurements of Schwartz and Mannes; Water Boiling at Reduced Gravities 83 2.6.9 Measurements of Judd and Merte; Freon Boiling at Normal and Mu]ti-g Accelerations 85 2.6.10 Microlayer Studies and Latent Heat Transport 89 2.7 SUMMARY AND CONCLUSIONS 90 CHAPTER 3 A LATENT-HEAT-BASED CORRELATION OF SATURATED NUCLEATE POOL BOILING HEAT TRANSFER 96 3.1 INTRODUCTION 96 3.1.1 Basic Approach and Outline 96 3.1.2 Ideal Treatment of Area of Influence Heat Transfer 97 Cvii) PAGE 3.1.3 Bulk Convection Correlations 98 3.1.4 Latent Heat Transport in Area of Bubble Influence 102 3.2 DERIVATION OF NEW CORRELATION 102 3.2.1 Expression for Latent Heat Transport 103 3.2.2 Expression for Total Heat Flux 116 3.3 APPLICATION OF CORRELATION 118 3.4 TESTING OF CORRELATION 119 3.4.1 Test Against High-pressure Water Data of Addoms 119 3.4.2 Test Against Low-pressure Ethanol Data of Bonilla and Perry 124 3.5 CONCLUDING COMMENTS 126 PART 2 EXPERIMENTAL STUDY OF MICROLAYER EVAPORATION 130 CHAPTER 4 FORMULATION OF PROBLEM 131 4.1 INTRODUCTION AND OUTLINE 131 4.2 REVIEW OF PREVIOUS MICROLAYER STUDIES 132 4.2.1 Local Surface Temperature Measurements 132 4.2.2 Temperature Measurements of Cooper and Lloyd 141 4.2.3 Scale Deposition Technique 147 4.2.4 Optical Reflection Technique 147 4.2.5 Interference Measurements of Sharp 149 4.2.6 Theoretical Predictions of Microlayer Thickness 154 4.3 SUMMARY AND DEFINITION OF PROBLEM 159 CHAPTER 5 BOILING APPARATUS 162 5.1 GENERAL REQUIREMENTS 162 Cvili) PAGE 5. 2 HEATING SURFACE 163 5. 2. 1 Specific Requirements 163 5. 2. 2 Electrically Conducting, Transparent Film on Glass 163 5. 2. 3 Stannic Oxide Films on Glass 164 5. 2. 4 Electrical Contacts: Indium Soldering 166 5. 2. 5 Configuration of Heating Film 169 5. 2. 6 Artificial Nucleation Site 169 5. 2. 7 Electrolytic Corrosion 171 5. 3 BOILING SYSTEM 173 5.,3.,1 Requirements 173 5. 3.,2 Overall Description 173 5.,3.,3 Mounting of Heating Surface 175 5.. 3..4 Tank and Water Jacket , 177 5..4 CONTROL AND MEASUREMENTS (NON-OPTICAL) 179 5..4,.1 Mean Heat Flux from Boiling Surface 179 5,.4,.2 System Pressure 181 5,.4..3 Bulk Temperature of Liquid 182 5,.4,.4 Mean Surface Temperature of Heater 183 CHAPTER 6 OPTICS OF MICROLAYER INTERFEROMETRY AND OPTICAL APPARATUS 186 6 .1 OUTLINE 186 6 .2 OPTICS OF MICROLAYER INTERFEROMETRY 187 6 .2 .1 Basic Concepts 187 6 .2 .2 Optical Analysis 188 6 .3 OPTICAL APPARATUS 197 6 .3 .1 General Requirements 197 6 .3 .2 Overall Description 198 6 .3 .3 Interference Beam Light Source and Image at Pinhole 198 6.3.4 Imperfect Collimation and Monochromaticity 203 6.3.5 Interference Beam Filters and Mirrors 212 (ix) PAGE 6.3.6 Bubble Profile: Illumination, Image Deflection and Distortion 213 6.3.7 High-speed Camera and Lens 214 6.3.8 Adjustment of System 215 CHAPTER 7 EXPERIMENTAL PROCEDURE AND DATA PROCESSING 218 7.1 OUTLINE 218 7.2 EXPERIMENTAL PROCEDURE 218 7.2.1 Establishing of Boiling Conditions 218 7.2.2 Final Preparations on Optical System 220 7.2.3 Execution of Run 220 7.3 DATA PROCESSING 221 7.5.1 Transcription of Optical Data 221 7.3.2 Time Base and Print Magnification 224 7.3.3 Microlayer Geometry: Analysis of Inter- ference Patterns 225 7.3.4 Bubble Volume 231 7.3.5 Dimensions Characterising Bubble Shape 233 7.5.6 Heat Transfer Parameters 234 CHAPTER 8 EXPERIMENTAL RESULTS 235 8.1 AIMS AND OUTLINE 235 8.2 TEST CONDITIONS 236 8.2.1 Heat Flux, Temperature and Pressure 236 8.2.2 Overall Bubble Behaviour 237 8.2.3 Bubble Involution and the Formation of Secondary Bubbles 8.3 ACCURACY OF REPORTED DATA 244 8.4 RESULTS 246 8.4.1 Methanol Runs M10 and M13 246 8.4.2 Methanol Runs M14, M19 and M20 252 8.4.3 Ethanol Runs E8 and E12 - 267 8.5 CONTRIBUTION OF VISIBLE MICROLAYER EVAPORATION TO BUBBLE VOLUME 267 8.6 COMPARISON OF EXPERIMENTAL AND PREDICTED MICROLAYER THICKNESSES 280 (x) PAGE CHAPTER 9 DISCUSSION 282 9.
Load more

Recommended publications
  • Investigation on the Mechanism of Heat Load Reduction for the Thermal Anti-Icing System
    energies Article Investigation on the Mechanism of Heat Load Reduction for the Thermal Anti-Icing System Rongjia Li 1, Guangya Zhu 2 and Dalin Zhang 2,* 1 College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; [email protected] 2 Interdisciplinary Research Institute of Aeronautics and Astronautics, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; [email protected] * Correspondence: [email protected] Received: 10 October 2020; Accepted: 6 November 2020; Published: 12 November 2020 Abstract: The aircraft ice protection system that can guarantee flight safety consumes a part of the energy of the aircraft, which is necessary to be optimized. A study for the mechanism of the heat load reduction in the thermal anti-icing system under the evaporative mode was presented. Based on the relationship between the anti-icing heat load and the heating power distribution, an optimization method involved in the genetic algorithm was adopted to optimize the anti-icing heat load and obtain the optimal heating power distribution. An experiment carried out in an icing wind tunnel was conducted to validate the optimized results. The mechanism of the anti-icing heat load reduction was revealed by analyzing the influences of the key factors, such as the heating range, the surface temperature and the convective heat transfer coefficient. The results show that the reduction in the anti-icing heat load is actually the decrease in the convective heat load. In the evaporative mode, decreasing the heating range outside the water droplet impinging limit can reduce the convective heat load. Evaporating the runback water in the high-temperature region can lead to the less convective heat load.
    [Show full text]
  • Electric Heating Load Forecasting Method Based on Improved Thermal Comfort Model and LSTM
    energies Article Electric Heating Load Forecasting Method Based on Improved Thermal Comfort Model and LSTM Jie Sun 1, Jiao Wang 1, Yonghui Sun 1, Mingxin Xu 1, Yong Shi 1, Zifa Liu 2 and Xingya Wen 2,* 1 State Grid Inner Mongolia Eastern Electric Power Co., Ltd., Economic and Technical Research Institute, Hohhot 010011, China; [email protected] (J.S.); [email protected] (J.W.); [email protected] (Y.S.); [email protected] (M.X.); [email protected] (Y.S.) 2 School of Electrical and Electronic Engineering, North China Electric Power University, Beijing 102206, China; [email protected] * Correspondence: [email protected]; Tel.: +86-18810119275 Abstract: The accuracy of the electric heating load forecast in a new load has a close relationship with the safety and stability of distribution network in normal operation. It also has enormous implications on the architecture of a distribution network. Firstly, the thermal comfort model of the human body was established to analyze the comfortable body temperature of a main crowd under different temperatures and levels of humidity. Secondly, it analyzed the influence factors of electric heating load, and from the perspective of meteorological factors, it selected the difference between human thermal comfort temperature and actual temperature and humidity by gray correlation analysis. Finally, the attention mechanism was utilized to promote the precision of combined adjunction model, and then the data results of the predicted electric heating load were obtained. In the verification, the measured data of electric heating load in a certain area of eastern Inner Mongolia were used. The results showed that after considering the input vector with most relative factors such as temperature and human thermal comfort, the LSTM network can realize the accurate prediction of the electric Citation: Sun, J.; Wang, J.; Sun, Y.; Xu, M.; Shi, Y.; Liu, Z.; Wen, X.
    [Show full text]
  • (56) November 2011
    Cl/SFB (56) Domestic Heating Commercial Heating Water Heating Solar PV Solar Thermal Heat Pumps Flame Effect Fires Portable Heating heatNovember 2011 bookSpace and water heating solutions for today – and tomorrow www.dimplex.co.uk “Wherever you go across the country, you’ll find Dimplex heating and hot water solutions. In its field, Dimplex leads the world – making life more comfortable, in more ways, in more places, than any other company.” Electric heating is the fuel of the future – it’s very versatile and offers levels of safety, reliability, cleanliness and comfort unmatched by other fuels. Dwindling supplies of North Sea gas, security of supply, The government’s microgeneration strategy also promotes the yo-yoing fuel prices and the need to reduce the UK use of low carbon sources, such as heat pumps and solar, carbon footprint are all impacting on the way we heat to help in tackling climate change and Dimplex is deeply our buildings. committed to the development of product in this area. Whilst a summary of these products is in this brochure, please visit The government has set the UK on a clear path towards a future www.dimplexrenewables.co.uk for full details of our renewable where electricity generated from nuclear power and sustainable solutions. sources will provide the cornerstone of our energy requirements – low carbon, inexhaustible and freely available. And of course energy efficient electric heating appliances are by definition ‘renewables ready’, meaning that as more renewable and low carbon sources of supply become available, electricity will increasingly be favoured over gas. Long term, there is little doubt that the future is electric, which already has a number of benefits.
    [Show full text]
  • Integrated Heating Systems Catalogue 2013 - 2014
    INTEGRATED HEATING SYSTEMS CATALOGUE 2013 - 2014 AHI Carrier South Eastern Europe AHI CARRIER SOUTH EASTERN EUROPE S.A. Business Territory Network ROMANIA Headquarters Bulgaria Branch 18, Kifissou Ave 25, Petar Dertliev blvd 104 42 - Athens 1324 - Sofia SERVIA BULGARIA GREECE BULGARIA Tel.: +30 210 6796300 Tel.: +35 929 483960 MONTENEGRO Fax: +30 210 6796390 Fax: +35 929 483990 FYROM Thessaloniki Branch Romania Branch ALBANIA 5, Ag. Georgiou str., Cosmos Offices 270d, Turnu Magurele str. Sector 4 GREECE 570 01 - Thermi Thessaloniki Cavar center - Bucharest GREECE ROMANIA Tel.: +30 231 3080430 Tel.: +40 214 050751 CYPRUS Fax: +30 231 3080435 Fax: +40 214 050753 COMPANY PROFILE Dating back to 1952, Carrier was the first air-conditioning company in Greece. In 1996, Carrier Hellas Air-Conditioning S.A. was established as a subsidiary of UTC with distribution and after sales services rights for Carrier, Toshiba & Totaline air-conditioning brands in Greece. Simultaneously, Carrier expanded its distribution rights to the Balkan area with offices in Romania & Bulgaria. In 2009, the company was renamed to Carrier South Eastern Europe Air-Conditioning S.A. signifying the distribution rights in Greece, Cyprus and the Balkan region. The first Semester of 2011, Carrier entered into an agreement to transfer its HVAC distribution and after-sales support operations in Greece, Cyprus & the Balkans to its existing AHI Carrier FZC joint venture. The company was renamed to AHI Carrier South Eastern Europe Air-Conditioning S.A. and continues to provide customers with high quality Carrier and Toshiba HVAC solutions, supported by dedicated after-sales service technicians and the Totaline parts and supply network.
    [Show full text]
  • Thermal Characterization of a Heat Transport System for Satellite Application
    Proceedings of the 2nd World Congress on Momentum, Heat and Mass Transfer (MHMT’17) Barcelona, Spain – April 6 – 8, 2017 Paper No. ICHTD 105 ISSN: 2371-5316 DOI: 10.11159/ichtd17.105 Thermal Characterization of a Heat Transport System for Satellite Application Paul Knipper, Sebastian Meinicke, Thomas Wetzel Karlsruhe Institute of Technology Kaiserstraße 12, Karlsruhe, Germany [email protected]; [email protected]; [email protected] Abstract - This contribution presents an approach for a mathematical model which is based on a detailed experimental characterization of a heat transport system as used in common satellite applications. The heat transported is being emitted from the electrical consumers inside the satellite. The present heat transport system consists of two loop heat pipes (LHP), which transport the heat obtained from four arterial heat pipes (AHP) to the heat sink outside the satellite using ammonia as a working fluid. Due to non- constant operation parameters, e.g. the thermal load and temperature of the heat sink, unwanted oscillations of the saturation temperature can be observed, which have a great impact on the operation temperature of the electrical consumers. In order to eliminate these oscillations and to ensure an optimal operation temperature an additional heat source, e.g. a heating film located on the compensation chamber of the LHPs, is being introduced into the system. This approach requires a fundamental knowledge of the thermal characteristics as well as a reliable control of the heating film. Therefore a mathematical model has been set up based on available concepts in literature and validated using experimental data from a novel test facility.
    [Show full text]
  • Analysis of the Use of Heating Film in the Heat Supply of Industrial Premises
    Vol. 9, No 2/2020, 113-118 DOI: 10.17512/bozpe.2020.2.14 Construction of optimized energy potential Budownictwo o zoptymalizowanym potencjale energetycznym ISSN 2299-8535 e-ISSN 2544-963X Analysis of the use of heating film in the heat supply of industrial premises Volodymyr Shepitchak 1 (orcid id: 0000-0001-5883-548X ) Vasyl Zhelyh 2 (orcid id: 0000-0002-5063-5077 ) 1 Lviv Polytechnic National University 2 Czestochowa University of Technology Abstract: The situation in the country and around the world needs new, better energy resources and ways to use them to save energy, and with it, the economic, ecological and social position of any state. Energy saving is a necessary issue for improving economic performance by reducing energy consumption while maintaining comfortable conditions. Large industrial buildings are a significant consumer of thermal energy. An effective approach is needed for the design of heating systems, taking into account the possible modes of their operation to ensure the rational use of energy resources. Keywords: film infrared heater, heating supply, energy savings, energy-efficient systems, heating, infrared heaters, radiant energy, working place, temperature regime Access to the content of article only on the base of the Creative Commons licence CC BY-NC-ND 4.0 Please, quote this article as follows: Shepitchak V., Zhelyh V., Analysis of the use of heating film in the heat supply of industrial premises, BoZPE, Vol. 9, No 2/2020, 113-118, DOI: 10.17512/bozpe.2020.2.14 Hygienic characteristics are one of the most important to consider in the general assessment of a heating system, especially when deciding on the use of a particular heating system in a room.
    [Show full text]
  • Installation Manual
    Carbon Heating Film • Easy to install. • Can be used as a sole room heating source (when cover at list 70% of the floor). • Does not circulate pollutants, dust, dirt, allergens or dry air. • May be installed on wall, ceiling, under laminate, engineered wood floors or tile. • Brings soothing warmth to specific rooms or cold areas. • Reduces energy up to 60% compared to forced air heating systems. • Maintenance free, strong and durable. • Complements your home heating system making rooms more comfortable. Read through this entire manual before starting installation. • All electrical connections must be made by a licensed electrician in accordance with national and local codes and standards. • Always join multiple heating film lines in parallel ONLY (never in series). • Always make sure to check the heating film before, during, and after installation of the floor covering. • Each thermostat requires a dedicated circuit at the breaker box. • Must not be installed in damp or wet areas as defined by the National Electrical Code. • Do not fold or wrinkle the heating film, walk on it unnecessarily, or drop heavy or sharp objects on it. • Never overlap the heating film. • Do not install electrical wires or pipes in the floor with the film. • Be sure underlayment contains no cellulose. • Install film only when room temperature is above freezing. • Leave a 6-inch space between film and fireplaces, chimneys, or hot water pipes. • Never use any type of insulation material on top of the heating film. • Do not install the healing mats directly over a foil backed insulation material. • When installing carpet a low tog underlay should be installed followed by a good quality hessian backed carpet.
    [Show full text]
  • Electrical Solar Panel Moisture Detector & Heater
    Project Number: AEE Electrical Solar Panel Moisture Detector & Heater A Major Qualifying Project Report Submitted to the Faculty of The WORCESTER POLYTECHNIC INSTITUTE In partial fulfillment of the requirements for the Degree of Bachelor of Science By _________________________ Jennifer Henriquez May 1, 2015 Approved: _____________________ Professor Alexander E. Emanuel, Advisor Abstract This Major Qualifying Project approaches the need to protect solar panel devices from inclement weather conditions that involve snow and ice by creating a temperature- and moisture-sensing unit and accompanying heating unit. The use of a thermistor, moisture sensor, operational amplifier, relay and heating unit working in unison help to accomplish the goal of reducing the amount of precipitation present during cold weather periods. 2 Acknowledgments I would like to first and foremost thank my mother for all of the endless, unconditional love and headstrong support she has provided during the completion of this project. Nunca me has dejado. I am also grateful to my Faculty and Project Advisor, Professor Alexander E. Emanuel, whose wisdom and patience were critical throughout this project and the rest of my WPI career. Finally, I would like to express my thanks to all of the professionals, family members, and friends who helped guide me with both advice and support. I couldn’t have done it without you. Table of Contents Abstract .......................................................................................................................................
    [Show full text]
  • Kapton® Forming Guide
    Forming with DuPont™ Kapton® Polyimide Films General Introduction 1. Film Selection DuPont™ Kapton® is a highly versatile engineering film used in All DuPont™ Kapton® films can be successfully formed, but hundreds of industrial and technical applications across a broad selection of a specific film type should be based on the range of industries. customer’s intended application. There are two base films in the product line-up: Kapton® HN, a crystalline polyimide and Kapton® Although Kapton® films can be easily punched into parts, forming JP, an amorphous polyimide. Both have good formability and the material has proven more difficult due to its special properties. resistance to most chemicals. If, however, an application calls for For many years, fabricators thought it could not be successfully added chemical resistance, a film in DuPont’s FN series should be formed. In response to numerous marketplace inquiries, DuPont considered. Also available are electrically conductive films has undertaken focused laboratory studies to better understand (Kapton® RS series), and thermally conductive films (Kapton® MT the forming process for Kapton® films. series). In addition to these commercial products, DuPont is This technical paper should be helpful to those who have an presently developing customized formable film. interest but little experience in forming methods, particularly in Films of Kapton® differ from one another in “formability” due to industries such as Speakers, Automotive, Heating and Ventilation their individual manufacturing processes. It is commonly thought and others where formed parts of Kapton® films are highly desirable. that JP films are easier to form than HN films. This may be true, but HN films have a slight stability advantage.
    [Show full text]
  • Corporate Brochure.Pdf
    YOUR WORLD LEADING PARTNER IN INTELLIGENT HEATING & CONTROL HEATER + MEASUREMENT = COMPLETE & CONTROL SOLUTION PRODUCT DEVELOPMENT We work together in a gate model to make sure we reach target in cost and production SOP Evaluation / Approval to Prototype Production Design / Testing & start: development: development: Pre-production Development: validation First serial (B-SAMPLES) (C-SAMPLES) (A-SAMPLES) delivery • Specification work • Initial testing • Production work / • Functional testing and • DVP Work • Project management • Feasibility • Verification and Final design evaluation • PPAP • Final report • First proposals analysis of A samples • Documentation and • Production engineering • Final design • Design preparation preparation • Prototype design QUALITY CERTIFICATIONS We strive to deliver the highest quality products combined Backer Calesco is certified with a flexible way of working. This permeates the whole by Intertek ISO 9001 · ISO 14001 process including sales, product development, manufactur- ing, customer service and logistics. Backer Calesco delivers Our facilities in China, Poland & Vietnam products that meet all relevant standards and tests, cer- are certified according to ISO 14001, tifying products according to customer specifications. We ISO 9001 and IATF 16949 are also able to carry out tests in modern labs, constantly Third-party approvals: improving our product performance and energy efficiency. VDE / ETL / S / UL 2 WE MAKE IT HAPPEN Our heating products together with our measurement and control devices offer our customers complete solutions. Our engineers will not only suggest solutions, they can also take part in and contribute to your product development by using our advanced technical tools and lab facilities. Our extensive experience and competence as well as our reliable quality and service guarantee your success.
    [Show full text]
  • P/V Stimson Shipyard Fy-2015
    ITB 2015-1200-2662 TECHNICAL SPECIFICATIONS P/V STIMSON SHIPYARD FY-2015 STATE OF ALASKA DEPARTMENT OF PUBLIC SAFETY DIVISION OF ALASKA WILDLIFE TROOPERS VESSEL SECTION 5700 EAST TUDOR ROAD ANCHORAGE, ALASKA 99507 (907) 269-0389 OFFICE (907) 269-5616 FAX 156.0’ – Length 38.0’ – Breadth 16.0’ – Depth 413.0 – Gross Tons ITB 2015-1200-2662 P/V STIMSON TECHNICAL SPECIFICATIONS TABLE OF CONTENTS GENERAL REQUIREMENTS Page Invitation to Bid (ITB) ................................................................................................................. 5 Work Scope ............................................................................................................................... 5 Quality Assurance ...................................................................................................................... 6 Change Orders .......................................................................................................................... 6 Pre-Shipyard Meeting ................................................................................................................ 7 Progress Meetings ..................................................................................................................... 7 Arrival at Contractor’s Facility .................................................................................................... 7 Re-delivery of the Vessel ........................................................................................................... 7 Requirements ............................................................................................................................
    [Show full text]
  • Investigation of a Root Zone Heating System for Greenhouse Seedling and Its Effects on Micro-Environment
    November, 2020 Int J Agric & Biol Eng Open Access at https://www.ijabe.org Vol. 13 No.6 47 Investigation of a root zone heating system for greenhouse seedling and its effects on micro-environment Fen He1,2, Yong Hou1,2, Kai Li1,2, Xiaoming Wei1,2,3*, Yaqing Liu1,2 (1. Academy of Agricultural Planning and Engineering, Ministry of Agriculture and Rural Affairs, Beijing 100125, China; 2. Key Laboratory of Farm Building in Structure and Construction, Ministry of Agriculture and Rural Affairs, Beijing 100125, China; 3. Beijing Research Center of Intelligent Equipment for Agriculture, Beijing 100097, China) Abstract: Under the extremely cold climatic condition, crops have to survive severe heat stress conditions, even if they are being kept in greenhouses. In the winter and spring of North China, the air and soil temperature is low inside the greenhouse, and when using a traditional heating system, the energy consumption is high. This paper reports on a study of different design solutions for a root zone heating system based on a kind of low temperature radiation material. Root zone heating systems offer increasing crop quality and productivity. A novel type of heat preservation and root zone heating system was applied in greenhouse seedling. And through multiple experiments, the effect of the root zone heating system on the ambient environment and seedbed surface was studied, and the heat preservation effect and heating uniformity were discussed. Results show that single-layer film covering on the root zone heating system can make the average temperature at night increase 1°C. And the average seedbed surface and substrate temperature can increase 11.3°C and 5.2°C, respectively.
    [Show full text]