A numerical-based evaluation framework for ventilation airflow forms in small office: Energy efficiency, comfort, cleanliness, and anti-infection level

Different mechanical ventilation strategies contribute variably to the ideal indoor microenvironment. In this study, the performance and differences in indoor microenvironments across 12 airflow forms are explored by the computational fluid dynamics (CFD) investigation. Utilizing the CFD dataset, a numerical decision-making framework is proposed to evaluate airflow forms based on multiple ventilation indicators. This framework allows for assessing and selecting airflow forms tailored to various design targets, such as energy efficiency, comfort, cleanliness, and anti-infection level, to balance resource and demand. The single-objective and multi-objective decision-making results exhibit distinct differences due to the varied performance of different airflow forms across various ventilation indicators. For single-objective decisions, the optimal ventilation designs are SV-CASE1 for energy efficiency, DV-CASE1 for comfort, CJV-CASE for cleanliness, and SV-CASE2 for anti-infection level. It is worth noting that the best performances are observed at the air change rate of 7ACH. When considering a multi-objective decision incorporating all four indicators, the ideal designs are DV-CASE1 for prioritized energy efficiency, comfort, or cleanliness and SV-CASE2 for primary focus on the anti-infection level. The research findings and the developed numerical framework provide building designers with a theoretical pre-design scheme to help select appropriate ventilation strategies tailored to specific design preferences.