The MAGIC test site is an area of 500m radius from St George’s Circus (near Elephant and Castle), in South London, UK (Figure 1). The choice was made to see the influence of four different emission sources (representing pollution sources from traffic, human activities, etc.). The first one is located in St George’s Circus (in red in figure 1 and in the video) and the second one is located at the west beginning of Westminster Road (in purple in figure 1 and in the video). The third and fourth emission sources are near the windows of the room at the third floor of the MAGIC case study building (Clarence Centre, London South Bank University): they are located on the London Road side and on the private courtyard of the Clarence Centre building, respectively (in blue and green, respectively, in figure 1 and in the video).
The animation below shows the changes of the pollution patterns for one isocontour/isosurface as a function of time for a westerly wind direction.
Figure 1 - Area of interest located in Elephant and Castle, South London, UK. Light gray building is the MAGIC case study building. Purple, red, blue and green circles represent the source locations. Colour code is the same as in the animation (L. Mottet, ICL, 2017).
The use of natural ventilation in buildings is aimed at ensuring the well-being of occupants - through good indoor air quality - as well as a reduction in energy demand (and the associated positive implications of reducing pollutant and carbon production). The indoor air quality and comfort are directly related to the outdoor air quality, and thus innovative and efficient solutions based on natural ventilation are needed for sustainable, healthy buildings.
To achieve these aims - reduction in energy demand and enhanced indoor air quality through natural ventilation - it is crucial first understand and predict accurately at high resolution the complex air flows and pollution concentrations at the building, block, borough and city scales. This can be accomplished using the Large Eddy Simulation (LES) method within the state of the art computational fluids dynamics (CFD) simulator - FLUIDITY (http://fluidityproject.github.io/), thus allowing the predictions of the turbulent air flows, pollution concentrations and temperature distributions in complex city geometries on finite-element, unstructured and adaptive grids. An important characteristic of the LES simulations for atmospheric problems is the inclusion of the turbulent inlet condition based on the synthetic eddy method.
The ultimate aim of this project is to find a cost-beneficial method in which to change the way our cities are developing. The Victorians improved health by covering sewage systems- let's see if we can do the same by improving air quality.
This project encompases a transdisciplinary research group from the Universities of Cambridge, Surrey and ICL, but we know that innovations take place beyond our reach, therefore we want to work with other academics and industry partners to further our work.
We want to inform decision makers to ensure the results of this project can benefit cities across the globe, therefore we are excited to share all elements of our research to ensure the sustainable development of cities for the future.
Animation - Area of interest located in Elephant and Castle, South London, UK. Purple, red, blue and green circles represent the source location; the colour code corresponds to figure 1, above (L. Mottet, ICL, 2017).
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