Air Quality, Ventilation & Environment Modeling

A Particle Model For Large Eddy Simulation
July 2000 – June 2001
Principal investigator: Qingyan Chen; Research Assistant: Mingde Su
Sponsor: MIT Lincoln Laboratory

Contaminant distribution in a room
Contaminant distribution in a room

In order to predict indoor air quality, it is essential to simulate the particletrajectories of contaminants in and around buildings. The information can be used to determine the best locations for placing sensors so that the building systems can provide best air quality. The study uses the Lagrangian model to trace the particle motion in a large eddy simulation program. Drag, buoyancy and Brownian forces are being considered in the motion equations. The modeling of momentum and energy exchange between air and particles is also established according to the theoretical analysis and experimental data.

Large Eddy Simulation of Airflow In and Around Buildings
July 1997 – September 2002
Principal investigator: Qingyan Chen
Research Assistants: Wei Zhang, Yi Jiang, and Mingde Su
Sponsors: National Science Foundation, Center for Indoor Air Research and Archilife Research Foundation

Instantaneous velocity and temperature distribution in a room predicted by LES

Large eddy simulation (LES) could be a next-generation tool to predict airflow in and around buildings, because LES is universal, has few or no adjustable model coefficients, and can provide more flow information. We are developing different LES dynamic subgrid models that are suitable for both indoor and outdoor airflows, and advance numerical algorithm to reduce computing costs. The new models and algorithm are being applied for natural ventilation design in buildings.