Airflow behavior and indoor/outdoor PM2.5 dispersion in different building–tree grouping patterns depend significantly on the building–tree layouts and orientation towards the prevailing wind. By using a standard k-ε model and a revised generalized drift flux model, this study evaluated airflow fields and indoor/outdoor relationships for PM2.5 resulting from partly wind-induced natural ventilat...

This theoretical study reports on the impact of perceived indoor air quality for productivity loss in air-conditioned office buildings. A new derivation of productivity calculation model based on pollution loads and contaminant removal effectiveness is applied and the effect of the improved ventilation efficiency on productivity is estimated. The findings show that the proportion dissatisfied i...

Understanding the behavior of airflow in a room is essential for building designers to provide the most efficient design of ventilation system, and having acceptable indoor air quality. This trend is the motive to solve the relationship between airflow parameters and thermal comfort. This paper investigates airflow characteristics, indoor air quality (IAQ), and the thermal comfort (TC) in a ven...

The fluctuation characteristic of airflow is one of the important factors to influence the indoor thermal environment and human thermal comfort, which attracts researchers’ interest in these years. This paper introduces the recent researches on the fluctuation characteristics of airflow conducted in Tsinghua University. Results show that there exist obvious differences and interesting connectio...

Algebraic multi-zone infiltration models (e.g. COMIS, CONTAM) have been developed to predict air flows and contaminant transport in complex buildings. However these models assume that each building zone is a well-mixed volume. This assumption is not appropriate to model large indoor spaces. We describe two simplified approaches, called zonal methods, to describe air flows in large indoor spaces...

An appropriate estimate of a building airflow network, which consists of infiltration and interzonal airflow, is important when determining indoor air quality, energy use, and for detecting contaminants. The objective of this study was to estimate the airflow network of a commercial building using CO2 as a tracer. CO2 is naturally present in the environment and is generated inside buildings by ...

Large eddy simulation (LES) with a dynamic subgrid-scale model (DSM) is a powerful tool to predict indoor airflow. Some DSM models need to average the model coefficient over a homogeneous direction or need to use an additional parameter. The others are too complicated. This study proposes a simple filtered dynamic subgrid scale model (FDSM) for indoor flow without a homogeneous direction. The p...

The authors of the article published recently in the European Respiratory Journal on the prevalence and correlates of airflow obstruction in >317 000 never-smoking Chinese subjects concluded that they found inconsistent associations with exposures to household air pollution and went on to outline what future work needed to be done [1]. In the first instance, they should present table 5 having r...

This study integrates photovoltaic (PV) system, building structure, and heat flow mechanism to propose the notion of ventilated Building-Integrated Photovoltaic (BIPV) walls. The energy-saving potential of the ventilated BIPV walls was investigated via engineering considerations and computational fluid dynamics (CFD) simulations. The results show that the heat removal rate and indoor heat gain ...