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Model Elements and Network Solutions of Heat, Mass and Momentum Transport Processes PDF

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Heat and Mass Transfer George L. Danko Model Elements and Network Solutions of Heat, Mass and Momentum Transport Processes Heat and Mass Transfer Series editors D. Mewes, Hannover, Germany F. Mayinger, München, Germany Heat and mass transfer occur in coupled form in most production processes and chemical-engineering applications of a physical, chemical, biological or medical nature. Very often they are associated with boiling, condensation and combustion processesandalsowithfluidsandtheirflowfields.Hencerheologicalbehaviorand dissipative heating also play a role. The increasing interplay of experimental research and computer-assisted evaluation and analysis methods has led to new results, which not only confirm empirical representations and their physical interpretation but, in addition, extend their previously limited applications significantly. The series covers all fields of heat and mass transfer, presenting the interrela- tionships between scientific foundations, experimental techniques, model-based analysisofresultsandtheirtransfertotechnologicalapplications.Theauthorsareall leadingexpertsin their fields. Heat and Mass Transfer addresses professionals and researchers, students and teachers alike. It aims to provide both basic knowledge and practical solutions, while also fostering discussion and drawing attention to the synergies that are essential to start new research projects. More information about this series at http://www.springer.com/series/4247 George L. Danko Model Elements and Network Solutions of Heat, Mass and Momentum Transport Processes 123 George L. Danko MackaySchool ofEarth Sciences andEngineering University of Nevada, Reno Reno,NV USA ISSN 1860-4846 ISSN 1860-4854 (electronic) Heat andMassTransfer ISBN978-3-662-52929-4 ISBN978-3-662-52931-7 (eBook) DOI 10.1007/978-3-662-52931-7 LibraryofCongressControlNumber:2016950864 ©Springer-VerlagGmbHGermany2017 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission orinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar methodologynowknownorhereafterdeveloped. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfrom therelevantprotectivelawsandregulationsandthereforefreeforgeneraluse. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authorsortheeditorsgiveawarranty,expressorimplied,withrespecttothematerialcontainedhereinor foranyerrorsoromissionsthatmayhavebeenmade. Printedonacid-freepaper ThisSpringerimprintispublishedbySpringerNature TheregisteredcompanyisSpringer-VerlagGmbHGermany Theregisteredcompanyaddressis:HeidelbergerPlatz3,14197Berlin,Germany To Emoke and Reka Danko Preface The present publication is the first chapter of the book in development entitled “Heat, Mass and Momentum Transport Network Models.” The reason for pub- lishing the first chapter before the completion of the entire book is to serve the practical need for technical reference for network models in ventilation, climate, and flow simulation inpipelinesystems. The early publication will also help those interested in the theory of transport processes and in new methods of network solutions. Coupled heat, mass, and momentum transport problems arise in many areas of science and engineering. With the increasing computational power coupled with new numerical solution techniques the ambition also grows for solving large-scale problems involving the flow and transport of scalar or vector substances. For this reason, network models are becoming widely used in industry, education and research,suchasVentsim,VnetPC,orVUMA,developedformodelingminesand interconnected tunneling systems. Such models are accessible to educators, stu- dents, scientists, or practicing engineers. Many of the new solution methods dis- cussed in the book are available in a special edition of Ventsim, providing a user-friendly graphical interface for easy model configuration for the solution of large-scale, coupled network models. Thetime-honoredtechniqueofnetworkapplicationisrevisitedinthebookusing flownetworksolutionsforalltransportprocesscomponentsforacoupledmodeling task. The conservation laws for mass, energy, and momentum are formulated first specificallyforthebranchesandnodesoftransportnetworksusingthecombination of the Eulerian and Lagrangean modeling methods. With the extension of Bernoulli’s original concept, a new solution is given for the flow field of viscous and compressible fluids as driven and governed by the balance of mechanical energy, coupled to the thermodynamics of the transport system. Applicable to simple or large-scale tasks, the new model elements and methods are built on first principles. Original formulations, their mathematical derivations, as well as appli- cations in numerical solution schemes are provided throughout the work. The numerical solution methods presented have been developed over two dec- ades starting with ventilation and cooling enhancement studies supported by the vii viii Preface U.S. Department of Energy (DOE), Yucca Mountain Nuclear Waste Repository Office and continued for the development and qualification of the MULTIFLUX networkcodeundergrantsfromtheScienceandTechnologyOfficeofDOE.Their support is gratefully appreciated. I acknowledge with my thanks the long-term financial support from the National Institute of Safety and Health (NIOSH), U.S., for model developments and tests for the improvement in mine safety and health. Themany research grantsfromotheragenciesandoperating minesstretchingover a decade from Nye County Natural Resources and Federal Facilities, Nevada; Barrick Goldstrike Mine and Newmont Gold Corporation, Nevada operations; as well as the Alpha Foundation are thankfully valued. The support from the Geothermal Project Office of DOE for opening a new application field for MULTIFLUX to model Engineered Geothermal Systems is gratefully recognized. The critical comments from students in the Mine 725: Heat, Mass, and Momentum Transport Process graduate course over the last few years as well as from colleagues at the University of Nevada, Reno, Mackay School of Earth Sciences and Engineering are all acknowledged with my thanks. Research Assistant Professor Davood Bahrami at the department deserves my warmest thanks for coding many of the network solution processes and setting up transport models for numerical tests and applications in various research projects. His participation in the software qualification of MULTIFLUX has been instru- mental in the development and commercialization work. The partnership support from Director Craig Stewart together with other software developers at Chasm Consulting, Australia, for the integration of the MULTIFLUX model into the Ventsim Visual software is thankfully recognized. The cooperative support of Christoph Baumann and others associated with Springer is also greatly appreciated. Reno, NV, USA George L. Danko Contents 1 Introduction... .... .... ..... .... .... .... .... .... ..... .... 1 1.1 Introduction .. .... ..... .... .... .... .... .... ..... .... 1 2 Phenomenological Properties and Constitutive Equations of Transport Processes .. ..... .... .... .... .... .... ..... .... 5 2.1 Density.. .... .... ..... .... .... .... .... .... ..... .... 5 2.2 Mixture Density, Concentration, Mass Fraction and Gas Law . .... ..... .... .... .... .... .... ..... .... 7 2.3 Temperature .. .... ..... .... .... .... .... .... ..... .... 8 2.4 Pressure . .... .... ..... .... .... .... .... .... ..... .... 9 2.5 Viscosity in Ideal Gases.. .... .... .... .... .... ..... .... 10 2.6 Viscosity in Real Gases .. .... .... .... .... .... ..... .... 12 2.7 Viscosity in Fluids . ..... .... .... .... .... .... ..... .... 15 2.8 Typical Viscosity Variations... .... .... .... .... ..... .... 16 2.9 Viscosity in Gas Mixtures .... .... .... .... .... ..... .... 17 2.10 Viscous Stresses in Three Dimensions ... .... .... ..... .... 17 2.11 Viscosity and Shear Stress in Turbulent Flow . .... ..... .... 19 2.12 Molecular Thermal Conductivity in Gases .... .... ..... .... 21 2.13 Thermal Conductivity in Gas Mixtures... .... .... ..... .... 25 2.14 Thermal Conductivity in Liquids and Solids... .... ..... .... 25 2.15 Thermal Conductivity and Diffusivity in Turbulent Flow.. .... 26 2.16 Mass Diffusivity in Gases. .... .... .... .... .... ..... .... 27 2.17 Mass Diffusivity in Gas Mixtures... .... .... .... ..... .... 30 2.18 Mass Diffusivity in Liquids ... .... .... .... .... ..... .... 30 2.19 Mass Diffusivity in Solids .... .... .... .... .... ..... .... 31 2.20 Diffusivity in Turbulent Flow.. .... .... .... .... ..... .... 32 2.21 Specific Heat . .... ..... .... .... .... .... .... ..... .... 33 2.22 Compressibility of Gas and Liquid.. .... .... .... ..... .... 34 2.23 Corollary of the Elements of Transport Processes... ..... .... 35 ix x Contents 3 Conservation of a Scalar Extensive in Integral Form... ..... .... 39 3.1 The Eulerian Shell-Balance Equation .... .... .... ..... .... 39 3.2 Eulerian Balance Equation with Lagrangean Internal Transport.. ..... .... .... .... .... .... ..... .... 40 3.3 ComparisonoftheEulerianandtheNewEulerian–Lagrangean Forms... .... .... ..... .... .... .... .... .... ..... .... 44 4 Conservation of a Scalar Extensive in Differential Form..... .... 47 4.1 Differential Species Balance in a Finite Cell... .... ..... .... 47 4.2 Differential Cell Balances with Substance Transport and Bulk Flow Conservation .. .... .... .... .... ..... .... 49 4.3 Directional, off-Centered Differential Substance Balance Equations . ..... .... .... .... .... .... ..... .... 51 5 Conservation of a Scalar Extensive in a State-Flux, Space-Time, Finite-Volume Cell.... .... .... .... .... ..... .... 57 5.1 State-Flux, Finite-Volume Cell for Unit Courant Number . .... 57 5.2 Multiple-Level, State-Flux, Finite-Volume Cell with Arbitrary Courant Number .... .... .... .... ..... .... 61 5.3 State-Flux, Space-Time Finite-Volume Block Model with Arbitrary Courant Number .... .... .... .... ..... .... 66 5.4 Extended Applications of the State-Flux, Space-Time Finite-Volume Block Model... .... .... .... .... ..... .... 72 5.5 Synopsis of the SFST Substance Balance Formulation.... .... 76 6 Conservation of Energy in Integral, Differential, and State-Flux Forms... ..... .... .... .... .... .... ..... .... 79 6.1 Integral Balance Equation for Energy.... .... .... ..... .... 79 6.2 Separation of the Mechanical and Thermal Components in the Integral Balance Equation for Energy... .... ..... .... 90 6.2.1 The Case of Zero Stagnant Volume ... .... ..... .... 91 6.2.2 The Case of Nonzero Stagnant Volume .... ..... .... 95 7 Transport Models for Mechanical Energy.... .... .... ..... .... 105 7.1 Differential Form of Mechanical Energy Balance in a Finite Cell for Unit Courant Number. .... .... ..... .... 105 7.2 State-Flux, Finite-Volume, Mechanical Energy Transport Model for a Network Branch .. .... .... .... .... ..... .... 108 7.3 State-Flux, Finite-Volume, Mechanical Energy Transport Model for a Network Junction . .... .... .... .... ..... .... 119 7.3.1 Mass Balance in a Junction Node. .... .... ..... .... 119 7.3.2 Mechanical Energy Balance for a Junction Node .. .... 122 7.4 State-Flux Network Model for Mechanical Energy Transport in Steady State . .... .... .... .... .... ..... .... 133 7.5 State-Flux Network Model for Time Dependent Mechanical Energy Transport.. .... .... .... .... ..... .... 140

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