Toward external coupling of building energy and airflow modelling programs

This paper presents the objectives and results of the initial stage of an ongoing research project on coupling of building energy simulation (BES), airflow network (AFN), and computational fluid dynamics (CFD) programs. The objective of the research underlying this paper is to develop and verify a prototype cooperative BES, AFN, and CFD design environment for optimization of building energy performance and indoor environment. The initial-stage work focuses on developing a Coupling Procedure Decision Methodology (CPDM), which is a decision support methodology to select the appropriate levels of resolution (BES, AFN, or CFD) and complexity (e.g., CFD only, BES and CFD uncoupled, BES and CFD thermally coupled, BES and CFD thermal and flow coupled) for airflow simulation in the context of building design. The selection of the appropriate level of resolution results from simulation-based sensitivity analysis. The selection of the appropriate level of complexity is an issue to be researched further. A practical case of integrated design of buildings and heating, ventilating, and air-conditioning (HVAC) systems is presented to highlight the use of CPDM. The paper finishes with directions for future work.