Accurate and rapid prediction of ventilation in built environment is highly desired for the design, construction and operation of energy-efficient, comfortable, and healthy buildings. Developing fast prediction techniques can advocate and accelerate a broader and better application of modeling tools for engineering practices, such as building emergency management, early-stage building and system design, and real-time system control and continuous optimization. This chapter first reviews and introduces the prevalent modeling techniques for built environment ranging from the simplest mixing model to the sophisticated field (computational fluid dynamics-CFD) model. The focus is put on those fast and accurate modeling methods, including zonal models, reduced-order models (ROMs), zero-equation turbulence models, coarse-grid CFD methods, and pressure-velocity decoupling algorithms. The chapter then demonstrates the application of some of these fast simulation techniques and methods for ventilation studies through several engineering and research case studies.

Chapter Contents:

• 11.1 Motivation
• 11.2 Overview of fast simulation techniques for built environment study
• 11.3 Mixing, nodal, and zonal airflow models
• 11.4 Field airflow models (CFD)
• 11.4.1 Turbulence model simplification
• 11.4.2 Coarse grid simulation
• 11.4.3 Velocity–pressure decoupling algorithm
• 11.4.4 Reduced-order model
• 11.5 Demonstration of fast simulation techniques for ventilation study
• 11.5.1 Zonal model simulation
• 11.5.2 Zero-equation turbulence model
• 11.5.3 Coarse-grid simulation
• 11.5.4 Velocity–pressure decoupling algorithm
• 11.6 Conclusions
• References

Inspec keywords: turbulence; reduced order systems; computational fluid dynamics; ventilation

Other keywords: pressure-velocity decoupling algorithms; early-stage building; computational fluid dynamics; zonal models; reduced-order models; real-time system control; ventilation system design; energy-efficient comfortable healthy buildings; continuous optimization; building emergency management; coarse-grid CFD method; zero-equation turbulence models

Subjects: Applied fluid mechanics; General fluid dynamics theory, simulation and other computational methods; Fluid mechanics and aerodynamics (mechanical engineering); Heat and thermodynamic processes (mechanical engineering)