Enhancing non-domestic Passivhaus auditoria ventilation design for improved indoor environmental quality. (15th April 2023)

• Record Type: Journal Article
• Authors: Mustafa, Murat; Cook, Malcolm J.; McLeod, Robert S.
• Is Part Of: Building and environment. Volume 234(2023)
• Publication Date: 2023-04-15
• Subjects: CFD -- Auditorium ventilation -- Thermal comfort -- nZEB -- IEQ -- Overheating; CFD Computational Fluid Dynamics -- nZEB near Zero Energy Building -- IEQ Indoor Environmental Quality; Buildings -- Environmental engineering -- Periodicals; Building -- Research -- Periodicals; Constructions -- Technique de l'environnement -- Périodiques; Electronic journals; 696
• DOI: 10.1016/j.buildenv.2023.110202
• Languages: English
• ISSNs: 0360-1323

Abstract

Abstract: Enhanced energy conservation strategies often involve tightly controlled ventilation flow rates. However, strategies that don't carefully consider ventilation rates can, in certain contexts, result in inadequate ventilation, with increased risks of poor indoor environmental quality and user acceptance. These design challenges are often exacerbated in non-domestic buildings with highly dynamic occupancy patterns. This study used computational fluid dynamics, supported by field measurements, to investigate the relationship between zonal supply air strategies and thermal comfort in the George Davies Centre, Leicester University, which is the largest non-domestic certified Passivhaus building in the UK. Ventilation strategies involving mechanical ventilation operating with heat recovery turned on and off, and natural ventilation systems were investigated in relation to their ability to maintain thermal comfort in an auditorium space characterised by high internal heat gains and tiered seating. The results show that, depending on the selected thermal comfort criterion, a thermally comfortable environment could be achieved when incoming air is in the range of 9–26 °C for mechanical ventilation with heat recovery and 17–29 °C for natural ventilation. These temperatures are referred to as 'limiting operating temperatures' in the paper. The work showed that in a temperate climate, thermal comfort could be maintained, for up to 80% of the year, using mixed mode ventilation, without space conditioning, in combination with intelligent design and control strategies. Operating in natural ventilation mode also provided increased fresh air supply capacity, a finding which is particularly relevant in the context of mitigating airborne viral transmission. Highlights: A CFD model was validated with data from UK's largest certified Passivhaus building. Thermal comfort is assessed under three different auditoria ventilation strategies. Natural, mechanical and heat recovery ventilation strategies are compared. Limits of each ventilation strategy are established for five UK climatic zones. Highest and lowest year-round thermal comfort and energy performance are identified.