KU Solar SKY PRO 10 CPC 58, Техническое руководство

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SKY PRO 1800 FORCED CIRCULATION MANUAL
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C
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Sample Wind Load Calculations for Solar Collectors
The sample calculations following are based on BS 6399-2 and BRE Digest 489, and are for illustrative
purposes only. Architects and specifiers should satisfy themselves that a particular solar collector is suitable
for the proposed installation location.
- Determining the Design Wind Load
BRE Digest 489 gives the following general equations for wind load used in the design of roof-mounted and
in-roof solar heating systems:
Roof-Mounted: F = q
s
C
p.net
C
a
A
ref
where
q
s
is the dynamic wind pressure at the reference height H for the installation, which can be obtained
from BS 6399-2 or the simplified method detailed in BRE Digest 489 based on the wind speed zones shown
in Figure B1. Unless otherwise defined, H can normally be safely taken as the maximum height of the roof
(the height to the ridge) to which the collector is attached
C
p.net
is the appropriate pressure coefficient for the system under consideration.
C
a
is the size effect factor from BS 6399-2. Ca may be safely taken as 1.0
A
ref
is the loaded area for the system or fixing under consideration. For overall loads on individual
collectors, Aref will be the area of the collector exposed to the wind.
If the roof-mounted collector is supported by, for example, four hooks, each hook, its fixings and the
supporting roof structure should be designed to resist a quarter of the wind force.
In-Roof: F = qs Cpt Aref D S
where
q
s
is the dynamic wind pressure at the reference height H for the installation, which can be obtained
from BS 6399-2 or or the simplified method detailed in BRE Digest 489 based on the wind speed zones
shown in Figure B1. Unless otherwise defined, H can normally be safely taken as the maximum height of the
roof (the height to the ridge) to which the collector is attached
C
pt
is the appropriate pressure difference coefficient for the system under consideration
A
ref
is the loaded area for the system or fixing under consideration. For overall loads on individual
collectors, Aref will be the area of the collector exposed to the wind.
D is the permeability factor (obtained from BS 5534)
S
is the substrate shielding factor (obtained from BS 5534)
Figure 3.7- c
3.8 Shade
Shade must be avoided on the collectors caused by obstacles so as to guarantee at least 4 hours of sunlight
at around midday during the winter solstice.