buradan - Yangın

TÜYAK BİLDİRİLER KİTABI
2009 PROCEEDINGS BOOK
Modules are supplied pre-assembled and pre mounted and ready
for installation on the ceiling of the tunnel. Each of the modules
includes 10 meter manifold stretch, discharge branch, nozzles and
installation clamps. Primary modules include selector valve with
filter and alarm valve.
For tunnels of up to 10.5 m width one only pipe with nozzles is needed,
with nozzles every 1.0 meters in the middle of the tunnel. In the case
of tunnel of more than 10.5 m additional pipes lines are needed.
Primary modules or activation modules
Figure 2. Activation Module
Primary modules or activation modules are supplied with standard
length of 10 meter. Each one of the modules contains:
w Main stainless steel manifold AISI 316 with unions at each end
PN16. Manifold is supplied with 2 ½”, 3”, 4” or 5” depending on
the hydraulics.
w Discharge branches: stainless steel pipe AISI 316 of 25 mm
diameter.
w Nozzles: Stainless steel nozzles AISI 316 mounted on the
branches. Minimum working pressure 8 bar. Average size of
drops at minimum pressure Dv90% 250 – 350 µm.
w Cut off valve: 1 ½” electrically activated valve.
w Filter: 1 ½” filter with 1 mm mesh.
w Control valve: Selector valve normally closed of 1 ½” electrically
operated with solenoid (12VDC o 24VDC) by means of panel
(included in price).
Secondary modules
Figure 3. Secondary Module
Secondary module is supplied with standard distance of 10 meter.
Each module contains:
w Main manifold: Stainless steel AISI 316 manifold with unions at
each end PN16. Manifold is supplied with diameters of 2 ½”, 3”,
4” o 5” depending on the hydraulics.
w Discharge branch: Stainless steel pipe AISI 316 of 25 mm
diameter.
w Nozzles: Stainless steel nozzles AISI 316 mounted on the
branches. Minimum working pressure 8 bar. Average size of
drops at minimum pressure Dv90% 250 – 350 µm.
4
TÜYAK 2009
Main benefits of this solution compared with high pressure water
mist solutions are:
w Electrical power consumption is lot less than high pressure water
mist solutions. This is a key point in many tunnels since they are
located in remote areas where it’s very costly to provide enough
electricity power to run ventilation and high pressure water mist
solutions.
w Same pump system can be used for hydrants without the need
to provide dedicated pump systems.
And, compared to prescriptive sprinklered solutions (Japanese
regulations):
w Tested with real fire scenarios that represents nowadays reality
in road tunnel. 6 mm/min Japanese Sprinkler design may not be
enough to control and suppress fires. Most tests carried out with
sprinklers were developed on 60’s and 70’s with mainly pool fires
. To the knowledge of the author sprinklers have been tested up
to approximately 25 MW fires.
w Uses 1/3 of the water amount. Consequently protection time
with same water reservoir is multiplied by 3. During Nihonzaka
Tunnel fire incident (11 July 1979) sprinklers managed to control
fire during one hour until reservoir ran dry. After that fire was
uncontrolled and grew dramatically. Fire brigades where unable
to extinguish the fire within that time and fire burned for 7 days.
Additionally this solution offers other advantages:
w Modular and pre assembled solutions easies installation of the
system reducing installation cost and disrupter time of the tunnel
services when installed in already in service tunnels.
Instrumentation
Figure 4. Runehamar test tunnel sketch
Tests were run in Runehamar tunnel in Norway. Test tunnel has a
total length of 1.6 km and has a slight upward pendent (1%) during
first 570 m and a downward pendent (2.1%) during the last 1000
m (Figure 4). Tunnel section is about 50 m2 with 9 m width and 6
m height.
Blue zone is the ventilation section where fans were located and
orange zone is where fires and water mist system were located
(Zero-point).
Acquisitions elements were installed at 40 m upstream section from
fire, at 5 m and 840 m downstream sections from fire (Figure 5).