Comprehensive optimization of urban building cluster morphology based on microclimate: A two-level optimization approach

Building cluster morphology plays a crucial role in shaping urban microclimate. Due to the global warming and urban expansion, urban microclimate environment has encountered several problems, like extreme heat or cold stress events. The practical design of building clusters often involves multi-scale, multi-faceted problems and contradiction points which is always challenging to solve. This paper proposes a "two-level" optimization framework for the layout and form design of building clusters in the aspect of engineering applications. A case design project is used to demonstrate the effectiveness of the proposed framework through detailed seasonal simulation. Results show that, comparing with the base case, the candidate design plan (i.e., Plan C) is attractive given the mean UTCI of the selected locations is lower by 0.73 degrees C in the cooling season noon and higher by 1.91 degrees C in the heating season at night. Results also indicate that the layout of a building cluster has greater impacts on the outdoor thermal environment during the heating season than the cooling season. Considering Plan C still has a heat/cold stress, further refinements have been performed on the local micro climate to adjust the wind corridor and solar radiation at the lower-level of architectural form. Finally, comprehensive design strategies have been synthesized for the building cluster design.