5.2.2. Concave roof geometry
Fig. 8b displays the volume flow rates for the concave roof geometries
(B2 e reference case e, B2x2_OR1 and B2x2_OR0.5) and
shows that the volume flow rates for the double-span cases
B2x2_OR1 and B2x2_OR0.5 increase with 4.2% and 28.0% compared
to case B2, respectively. Contours of CP and jVj/Uref are given in
Fig. 10. It can be seen that the flow remains attached to the top of
the first-span roof and that it also reattaches to the top of the
second-span roof (Fig. 10d and f). The internal pressure in the
building is lower in case B2x2_OR0.5 (0.02 < CP < 0.08) than in
case B2 (0.17 < CP < 0.25) and B2x2_OR1 (0.16 < CP < 0.24). In
Table 2 it can be seen that also for the concave roof geometry the
pressure at the inlet opening is lower for B2x2_OR0.5 (CP ¼ 0.29)
than for B2x2_OR1 (CP ¼ 0.4), with pressures at the outlet openings
that are about equal. However, due to the lower internal pressure