Ventilation impact on indoor air quality problems in partitioned offices

Complaints of many indoor air quality problems occur in partitioned offices. Ventilation is one way to control the contaminant distribution and to provide better indoor air quality within the office. A comprehensive research of the ventilation impact on indoor air quality problems in partitioned offices was conducted in this thesis. Experimental measurement and computational fluid dynamics (CFD) simulation methods were applied. The study results show that, the supplied air was uniformly distributed in the ventilated area under various conditions. At the same time, the contaminant distribution was influenced by almost all kinds of parameters in the office. It was the room air flow pattern but not the uniformity of the supplied air distribution which influenced the contaminant distribution in the office. The results also indicate that the contaminant distribution in a mechanically ventilated partitioned office need to be studied individually according to the different cases. CFD simulation is an efficient tool for such kind of studies. The air inflow condition is one of the most important parameters affecting the air flow pattern and contaminant distribution in a mechanically ventilated room. Because of the complex geometry of the supply air diffuser and computer capacity, the conventional method of describing the supply air diffuser boundary conditions in CFD simulation may not well define the air inflow condition. The inaccurate description to the air inflow condition could lead to a totally unrealistic simulation result of the air flow inside the office. A new method to correctly describe the diffuser boundary conditions in CFD simulation was proposed in this thesis. The model prediction was validated with the experimental data in a literature and the results from the experimental part of this thesis. The CFD predictions applying the new method were in good agreement with the experimental results