Analysis of the heating energy demand of a generic shop with an air curtain by coupled CFD and BES

Air curtains are devices used to separate two different environments, in terms of air temperature and/or concentration of species. One of the main applications of air curtains consists in their placement at the open entrances of commercial buildings in order to provide an aerodynamic seal that reduces air infiltration through the entrance while allowing the unobstructed passage of people and equipment. From an energy conservation perspective, it is known that air infiltration can be responsible for a major share of the total energy losses occurring in a building. Therefore, it is relevant to understand the impact that infiltration through continuously open entrances can have on the energy demand of a building, and to comprehend how effective the placement of air curtains is as a strategy to restrict infiltration and reduce related building energy losses in such scenarios. This paper presents a study on the dynamic effect of weather conditions, during the winter season, on the total infiltration and the resulting heating energy demand of a generic retail building with an entrance door including and excluding an air curtain. For this purpose, an automated direct coupling of computational fluid dynamics (CFD) and building energy simulation (BES) is introduced to simultaneously model the complex dynamics and transport processes of the air-curtain jet flow and its contribution to the overall thermal balance of the building.