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Numerical Modeling of a Thermal-Hydraulic Loop and Test Section Design for Heat Transfer Studies in Supercritical Fluids

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Numerical Modeling of a Thermal-Hydraulic Loop and Test Section Design for Heat Transfer Studies in Supercritical Fluids Numerical Modeling of a Thermal-Hydraulic Loop and Test Section Design for Heat Transfer Studies in Supercritical Fluids By Daniel McGuire A thesis submitted to The Faculty of Graduate and Postdoctoral Affairs in partial fulfilment of the degree requirements of Masters of Applied Science Ottawa-Carleton Institute for Mechanical and Aerospace Engineering Department of Mechanical and Aerospace Engineering Carleton University Ottawa, Ontario, Canada May 2011 Copyright © 2011 - Daniel McGuire Library and Archives Bibliotheque et Canada Archives Canada Published Heritage Direction du 1+1 Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-93516-3 Our file Notre reference ISBN: 978-0-494-93516-3 NOTICE: AVIS: The author has granted a non­ L'auteur a accorde une licence non exclusive exclusive license allowing Library and permettant a la Bibliotheque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans le loan, distrbute and sell theses monde, a des fins commerciales ou autres, sur worldwide, for commercial or non­ support microforme, papier, electronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in this et des droits moraux qui protege cette these. Ni thesis. Neither the thesis nor la these ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent etre imprimes ou autrement printed or otherwise reproduced reproduits sans son autorisation. without the author's permission. In compliance with the Canadian Conformement a la loi canadienne sur la Privacy Act some supporting forms protection de la vie privee, quelques may have been removed from this formulaires secondaires ont ete enleves de thesis. cette these. While these forms may be included Bien que ces formulaires aient inclus dans in the document page count, their la pagination, il n'y aura aucun contenu removal does not represent any loss manquant. of content from the thesis. Canada Abstract A numerical tool for the simulation of the thermal dynamics of pipe networks with heat transfer has been developed with the novel capability of modeling supercritical fluids. The tool was developed to support the design and deployment of two thermal-hydraulic loops at Carleton University for the purpose of heat transfer studies in supercritical and near-critical fluids. First, the system was characterized based on its defining features; the characteristic length of the flow path is orders of magnitude larger than the other characteristic lengths that define the system's geometry; the behaviour of the working fluid in the supercritical thermodynamic state. An analysis of the transient thermal behaviour of the model's domains is then performed to determine the accuracy and range of validity of the modeling approach for simulating the transient thermal behaviour of a thermal-hydraulic loop. Preliminary designs of three test section geometries, for the purpose of heat transfer studies, are presented in support of the overall design of the Carleton supercritical thermal-hydraulic loops. A 7-rod-bundle, annular and tubular geometries are developed with support from the new numerical tool. Materials capable of meeting the experimental requirements while operating in supercritical water are determined. The necessary geometries to satisfy the experimental goals are then developed based on the material characteristics and predicted heat transfer behaviour from previous simulation results. An initial safety analysis is performed on the test section designs, where they are evaluated against the ASME Boiler, Pressure Vessel, and Pressure Piping Code standard, required for safe operation and certification. To my parents and brother: for all your support. Acknowledgements It is with heartfelt gratitude that I acknowledge the support and guidance of (now) Drs. Dylan McGuire and Chukwudi Azhi. Their contributions throughout my graduate education proved invaluable, providing personal encouragement as well as lending their weight of knowledge and experience to my endeavours. In addition I would like to extend my sincere appreciation of the opportunity provided by Professor Metin Yaras and his support and guidance through the process. His mentorship and insight has provided a unique and rewarding educational experience that left me enriched for the journey. I have been truly fortunate to have met these people and shared this experience with them. Table of Contents Abstract Acknowledgements ii Table of Contents iii List of Figures vi List of Tables x Nomenclature xii Chapter 1 Introduction 1 1.1 Background .................................................................................................................. 1 1.1.1 Carleton Supercritical Facility ...............................................................................2 1.2 Objectives ..................................................................................................................... 6 1.2.1 Development of Predictive Tools ..........................................................................7 1.2.2 Development of Test sections to meet Experimental Goals ...............................8 Chapter 2 Literature Survey 9 2.1 Modeling the Transient Thermal Response of a Discretized System ...................... 10 2.2 Modeling One-Dimensional, Compressible Flow ...................................................... 16 2.2.1 Capturing Turbulence Effects .......................................................................... 19 2.3 Test Section Design ....................................................................................................31 Chapter 3 Modeling a Thermal-Hydraulics Loop 32 3.1 Numerical Methods ...................................................................................................34 3.2 Fluid Modeling ........................................................................................................... 36 3.3 Solid Material Modeling .............................................................................................39 3.4 Discretization and Numerical Stability Analysis ........................................................40 3.4.1 Discretization of Governing Equations ..............................................................41 3.4.2 Stability Analysis .................................................................................................44 3.5 Modeling and Meshing of Loop Components ..........................................................46 3.5.1 Piping Modeling ..................................................................................................46 3.5.2 Component Modeling .........................................................................................49 3.5.3 Meshing ................................................................................................................... 55 3.6 Algorithm ................................................................................................................... 58 3.7 Conclusion .................................................................................................................. 62 Chapter 4 Numerical Simulation Results 67 4.1 Time Step Size ............................................................................................................67 4.2 Grid Independence ....................................................................................................68 4.3 Benchmarks and Quality Assurance ......................................................................... 72 4.3.1 Conduction in the Fluid Domain ........................................................................ 73 4.3.2 Convection in the Fluid Domain ........................................................................ 75 4.3.3 Conduction in the Solid Domain ........................................................................ 77 4.3.4 Fluid Property Handling ..................................................................................... 80 4.4 Simulation Results ......................................................................................................81 Chapter 5 Material Selection 88 5.1 High Temperature Alloys ...........................................................................................88 5.2 Corrosion .................................................................................................................... 89 5.3 Ceramic Coatings .......................................................................................................92 5.4 Electrical Resistivity and Conductor .......................................................................... 93 Chapter 6 Preliminary Test section Design 96 6.1 Background ................................................................................................................96 6.2 Test section Geometry .............................................................................................103 6.2.1 Loop Interface ...................................................................................................104
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