Coupling building energy simulation and computational fluid dynamics: Application to a two-storey house in a temperate climate

This article reports the coupling of a building energy simulation (BES) made with TRNSYS with a computational fluid dynamics (CFD) simulation made with ANSYS FLUENT and its application to a typical Belgian two-storey house. The coupling scheme developed in this study aims to improve the overheating prediction for buildings. This phenomenon is becoming increasingly frequent in Northern Europe due to increased insulation and a lack of sun protection and natural cooling strategies. Complementary contributions of the two numerical approaches are underlined and used to obtain accurate results in an acceptable computing time, even in a thermally stratified room. The space and time coupling is discussed to obtain an optimised tool in which BES is in charge of the primary portion of the effort, while CFD intervenes punctually on one room of interest. The numerical results are compared both qualitatively and quantitatively to the experimental results, and the improved accuracy of the coupled tool compared with a standalone BES is underlined.