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. 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.