Optimal design of duct openings in naturally-ventilated buildings

摘要

Natural-ventilation systems are used in sustainable buildings. In order to promote naturalventilation by airflow, these buildings have openings that connect rooms and commonspaces. These openings, while supporting airflow, transmit sound from one space to theother, leading to poor noise isolation and speech privacy. The performance of theseopenings needs to be optimized – meaning the sound isolation of these openings has to beimproved, with minimal impact on the airflow performance. Previous work by Bibbyinvestigated openings in thin partitions. This paper addresses the problem of openings inthick partitions, which essentially are short ducts, as well as long ducts that deliver air-flowto different building levels through the stack effect, by prediction and experimentalvalidation. An objective function for optimal air-flow and sound attenuation was developedusing surrogate models that describe the acoustics and fluid dynamics in the duct. Thesesurrogate models were constructed using symbolic regression from Finite Elementsimulations. Different configurations of sound absorbers (duct lining and baffles) weretested to identify optimal designs based on objective function constraints. The surrogatemodels were then validated experimentally in a scale-model facility, applying appropriatescaling laws.