analysis of the influences of solar radiation and façade glazing ...

3.4 Testing of a building indoor environment during the warm period 79
3.4 Testing of a building indoor environment during the warm
period
The simulation was carried out to audit the thermal environment in the apartments during
the warm period. Calculations were performed with the following assumptions:
• the cooling system is turned off,
• mechanical intensive night ventilation with outside air and at a variable flow rate
was realized.
Reduction of gains from solar radiation during the summer was performed by:
• protection shields made by movable glass parts printed with various patterns, which
were positioned on a movable rails construction on the level of the building facade
in front of the balconies,
• alternatively an internal or external window shade with high reflect parameters.
The zone’s thermal environment was defined by using: Predicted Mean Vote (PMV),
Predicted Percentage of Dissatisfied (PPD) and operative temperature θO given by:
( A)
MR
θO = Aθa , i + 1−
θ , (3.5)
where:
A = hr / (hc + hr)
hr – surface heat transfer coefficient by radiation,
hc – surface heat transfer coefficient by convection,
θa,i – the air temperature inside the zone-i,
θMR – the mean radiant temperature.
The calculation of the mean radiant temperature was done by equation (3.6).
n
4 ∑
i=
1
θ = F θ ,
MR
where:
4
o−i
i,
r
n – the number of surfaces inside the zone-i,
Fo-i – the view factor of the human body,
– the radiant temperature of the isothermal surface.
θi,r
(3.6)