A59 -- Indoor Airflow Modeling (SI)

When trying to determine best design practices for specific indoor spaces, building designers may encounter uncertainties regarding control of airflow, indoor air quality, thermal comfort, or heat transfer. Computer models allow designers to quantitatively evaluate multiple designs quickly and with a good degree of accuracy. This chapter expands on the general guidance of Chapter 13 in the 2021 ASHRAE Handbook—Fundamentals, with the addition of industry-specific advice and examples to aid designers in modeling indoor applications. The two methods featured in this chapter are computational fluid dynamics (CFD) and multizone (MZ) modeling. Although this chapter is intended to be a fast-start guide for modeling indoor airflow, engineers should have a basic understanding of fluid mechanics and the modeling principles described in Chapter 13 of 2021 ASHRAE Handbook—Fundamentals. PRELIMINARY CONSIDERATIONS COMPUTATIONAL FLUID DYNAMIC (CFD) METHOD Terminology Overview of CFD Simulation Process CFD EXAMPLES Simple Office with Diffusers and Returns Example Chilled Beam Example Displacement Ventilation Example Data Center Design Example Viral Containment in Hospital Ward Example Natural Ventilation Example Industrial Warehouse Example MULTIZONE SIMULATION METHOD Multizone Simulation of a Typical Office Building