Variability of Thermal Stratification in Naturally Ventilated

Building energy simulation programs often use standard thermal comfort indices and thresholds as boundary conditions. However, most of them focus on comfortable indoor hydrothermal levels, rather than spatial distributions. This paper investigates internal temperature vertical stratification in naturally ventilated residential buildings. To evaluate this effect, a field study was carried out in Greater London during the winters of 2012 and 2013. This allowed the monitoring of indoor thermal stratification amplitude and frequency variability in real settings. To follow this investigation, CFD models simulating heat and mass transfer within the airflow are developed, and validated from the experimental results. To conclude, this paper reviews the potential for building-in greater thermal variability into existing comfort simulation tools.