Coupled simulations for naturally ventilated residential buildings

Abstract

The study of thermal environment of naturally ventilated buildings is significant for providing a thermally comfortable and energy saving indoor environment, which is important for both architects and engineers. However, there is no appropriate simulation tool to predict indoor thermal environment of natural ventilation. In order to improve accuracy and efficiency of simulation tools to assess the potential of natural ventilation, a coupling program with a text-mode interface between building simulation (BS) and computational fluid dynamics (CFD) simulation is developed for thermal prediction in time series. Coupled simulations were validated with two different methods: full CFD simulation and field measurement. In the full CFD validation, multi-zone cases were investigated to validate coupled simulation results with full CFD results. In the field measurement validation, the measuring results for a typical naturally ventilated HDB building in Singapore has been used to compare with coupled simulation results. It was concluded that the building simulation alone is difficult to accurately predict indoor thermal environment. This paper suggested that coupled simulations between BS and CFD are able to improve the accuracy and efficiency in natural ventilation prediction by taking pressure boundary conditions for indoor CFD simulation.