Framework for integrated multi-scale computational fluid dynamics simulations in natural ventilation design

Abstract

The wind flow field constitutes an important input parameter for computational fluid dynamics (CFD) simulations that are used in architectural design for the design and analysis of natural ventilation strategies.  Despite indications that the wind flow field may vary between places, CFD simulations that do not adequately account for this potential variation are still commonplace. This may significantly compromise the integrity and accuracy of the CFD simulations. This study was a two-pronged investigation with the ultimate objective of contributing towards efforts aimed at improving the accuracy of the CFD simulations. Firstly, a framework for integrated meso-scale and micro-scale CFD simulations was developed. Secondly, the newly developed framework was then implemented by deploying it to study the variation of the wind flow field between a reference meteorological station, and a selected local building site. The findings confirmed the indications that the wind flow field might vary spatially. The integrated multi-scale framework that was developed as part of the study was not only able to capture the wind flow field variation, but it also provided a way to quantify it, ultimately, leading to the generation of a more accurate wind flow field characterization representative of the local conditions. Through its ability to integrate multiple spatial scales that typically influence one another, this framework can help to enhance the accuracy and integrity of the CFD simulations that are used for natural ventilation design. Practical application: The findings from this study can be particularly useful when undertaking spatially integrated CFD simulations to design and analyse natural ventilation strategies in the building design process.