Speaker: Prof Paul Linden
The imperative to reduce energy consumption in cities drives a need to replace air conditioning with other forms of low-energy ventilation in buildings. Natural ventilation is an obvious candidate and, since it requires exchange between the interior of a building and the outside environment, the relative level of a contaminant inside and outside is very important in determining the quality of the internal environment.
In this talk I will describe the basic fluid mechanics behind low-energy natural ventilation and the implications for contaminant movement within buildings. I will show that depending on the location of the pollution source the distribution within a building can differ significantly from one case to another. Using results from a recent field study in London I will also show that pollution levels in the city vary significantly in time and space and that these variations must be taken into account when operating a naturally ventilated building. Finally, I will discuss an ongoing project that aims to provide an integrated modelling system that will provide a tool to make accurate assessments of the potential to reduce energy consumption and excess heat emissions from buildings.