Passive Cooling Strategies - Low Energy Cooling for Sustainable Buildings - page 80

Figure 3.21 Hours in the year 2005 when the room air temperature exceeded a given value (only
working days from 08:00 to 18:00 were considered). The key orders the rooms on the ground floor (GF)
and top floor (TF) from left to right
Night ventilation measurements and simulations showed that complete discharging
of internal surfaces during longer hot periods in summer can only be achieved with
very high air change rates and high heat transfer coefficients. In real building situations,
especially close to the neutral zone, the flow direction is not necessarily from the inside
to outside so that the effective air changes for cooling are often lower than measured.
Correct design of the neutral zone placement (as high as possible) is important for
effective natural night ventilation. In the building project investigated, wind-induced
Figure 3.22 Hours in the year 2006 when the room air temperature exceeded a given value (only
working days from 08:00 to 18:00 were considered). The key describes the rooms from left to right
(ambient air, ground floor (GF), top floor (TF))