Computational Modeling of Pulverized Coal Fired Boilers.pdf
PC fired boilers have highly turbulent flow, complex gas-solid flow, coal combustion, and radiative heat transfer. Over the years, computational fluid dynamics (CFD) tools have evolved as powerful design and predictive tools for simulating complex equipment. This book describes the methodology needed to formulate computational fluid dynamics (CFD) models to simulate boilers (typically 200 MWe). It also provides guidelines on implementing it in commercial CFD solvers, like Ansys Fluent, and provides various case studies to understand the effect of operating conditions on boiler performance.
"This book aims to provide the reader with a pragmatic approach to modeling pulverized coal fire boilers. Because of the importance of improving the efficiency of such systems and reducing CO2 emissions, this book would serve as a good reference text for future engineers engaging in handling pulverized coal fire boilers. The close link between CFD and reactor models represents the unique feature of this book." -Guan Heng Yeoh, Associate Professor, School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, Australia
Introduction Pulverized coal fired boiler Computational modeling Organization of this book Towards Computational Modeling of PC boilers Overall approach Engineering design models Particle level models Boiler level models Computational fluid dynamics based models Reactor network models Applying computational models to practice Summary Kinetics of Coal Devolatilization and Combustion: Thermo-gravimetric Analysis (TGA) & Drop Tube Furnace (DTF) Coal devolatilization and combustion Coal characterization using thermogravumetric analysis (TGA) Typical example of a TGA experiment Processing of TGA data Coal characterization using drop tube furnace (DTF) Typical example of a DTF experiment Processing of DTF data Summary and conclusions CFD Model of a Pulverized Coal Fired Boiler Formulation of CFD model of a PC boiler Overall continuity and momentum balance equations Species balance equations Energy balance equations Formation NOx and SOx Particle deposition and heat transfer through deposit layer CFD simulations of a PC boiler Numerical simulation/simplifying geometry of PC boiler Simulation of cold air velocity tests (CAVT) Simulation of a typical 210 MWe pulverized coal fired boiler Influence of operating parameters on boiler performance Summary and conclusions Reactor Network Model of a PC Fired Boiler Approach to develop reactor network model (RNM) Formulation of Reactor Network Model (RNM) from CFD simulations Formulation of reactors/zones in a PC boiler Formulation of reactor network from the identified zones Model equations and solution Continuous phase Dispersed phase Homogenous gas phase reactions Radiation Solution of model equations Application of RNM to a typical 210 MWe PC boiler Summary and conclusions Application to practice Performance enhancement using computational models Application of CFD models to PC boilers Formulation of a CFD model Solution of model equations Examination and interpretation of simulated results Application of simulated results for performance enhancement Application of reactor network models to PC boilers Common pitfalls in computational modeling Summary Summary and path forward Notations Author Index Subject Index