Assessment of different HVAC configurations in a Conference Room with thermal stratification for improved microclimate conditions

The paper aims to investigate the microclimate conditions within a conference room, namely the chapel of Villa San Saverio presently housing the "Scuola Superiore" of the University of Catania, as a case study. Initial surveys of the chapel involved monitoring air temperature and relative humidity. Subsequently, numerical simulations utilizing a simplified computational fluid-dynamics (CFD) model, built with DesignBuilder software, were conducted and validated against measured values. Three scenarios were simulated, encompassing the existing state without thermal systems and two configurations incorporating both air-conditioning and ventilation. Results indicate that, for optimal comfort, a lightweight radiant floor heating system, coupled with a floor-level ventilation system for air renewal near occupants, proves superior to floor-level fan coils and high ventilation channels. This finding is further supported by a basic energy analysis comparing the two HVAC options. The analysis considers winter ventilation effectiveness, emitter water temperature, COP value of the heat pump, and electricity consumption of the various components. This comprehensive approach provides valuable insights for enhancing comfort and energy efficiency in enclosed spaces, offering practical applications for similar environments. Key words. Microclimate, historic building, HVAC systems