Tyco Fire Suppression & Building Products ANSUL AQUASONIC, Руководство по проектированию, установке, заправке и обслуживанию

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SECTION IV
3-1-2010 Page 4-7
Design
6h – Determine Which Atomizer has the Greatest Total
Pipe Pressure Loss (TPPL)
Total Pipe Pressure Loss (TPPL) is determined by combin-
ing the pressure loss calculated for Supply Line (A) and the
pressure loss from the appropriate Branch lines (either: B
and C, B and D, E and F, or E and G) for each atomizer.
Example:
Pressure loss in Supply Line A (Step 6a) = 4.43 psi
(0.305 bar)
Pressure loss in Branch Line B (Step 6b) = 2.16 psi
(0.149 bar)
Pressure loss in Branch Line C (Step 6c) = 0.18 psi
(0.012 bar)
Pressure loss in Branch Line D (Step 6d) = 0.63 psi
(0.043 bar)
Pressure loss in Branch Line E (Step 6e) = 2.43 psi
(0.168 bar)
Pressure loss in Branch Line F (Step 6f) = 0.18 psi (0.012
bar)
Pressure loss in Branch Line G (Step 6g) = 0.63 psi
(0.043 bar)
Atomizer 1:
Supply Line A, 4.43 psi (0.305 bar) + Branch
Line B, 2.16 psi (0.149 bar) + Branch Line C, 0.18 psi
(0.012 bar) = 6.77 psi (0.467 bar) total pressure loss in
system.
Atomizer 2:
Supply Line A, 4.43 psi (0.305 bar) + Branch
Line B, 2.16 psi (0.149 bar) + Branch Line D, 0.63 psi
(0.043 bar) = 7.22 psi (0.498 bar) total pressure loss in
system.
Atomizer 3:
Supply Line A, 4.43 psi (0.305 bar) + Branch
Line E, 2.43 psi (0.168 bar) + Branch Line F, 0.18 psi (0.012
bar) = 7.04 psi (0.485 bar) total pressure loss in system.
Atomizer 4:
Supply Line A, 4.43 psi (0.305 bar) + Branch
Line E, 2.43 psi (0.168 bar)+ Branch Line G, 0.63 psi (0.043
bar) = 7.49 psi (.516 bar) total pressure loss in system.
Therefore, atomizer 4 has the greatest TPPL for this
system.
6i – Calculate Elevation Head Loss (EHL)
Determine vertical distance between system tank bottom
and the atomizer. Referring to example in Figure 4, vertical
pipe rise from the tank connection to the atomizers, 12 ft
(3.66 m) + vertical pipe rise from bottom of tank to tank
connection piping, 4 ft (1.22 m) = 16 ft (4.88 m) of 3/4 in.
pipe.
To determine EHL, multiply the total vertical pipe rise, 16 ft
(4.88 m) by the constant 0.433 psi/ft (0.0979 bar/m) = EHL
= 6.93 psi (0.478 bar)
EHL = 6.93 psi (0.478 bar)
6j – Calculate Total Atomizer Pressure (TAP)
Total atomizer pressure is determined using the pressure
loss from the atomizer with the greatest TPPL for the
purpose of selecting the appropriate atomizer assembly.
Note:
On larges systems, it may be necessary to select
different atomizer assemblies depending on the difference
in pressure loss from the atomizer with the greatest TPPL
to the atomizer with the lowest TPPL.
For this step, it is assumed that there is always 115 psi
(7.929 bar) available at the water outlet on the water supply.
When the atomizer is located
above
the water supply
piping outlet on the system:
Total Atomizer Pressure (TAP) = 115 psi (7.929 bar) (pres-
sure available at outlet of the water supply) – (Total Pipe
Pressure Loss (TPPL) + Elevation Head Loss (EHL))
TAP = 115 psi (7.929 bar) – (TPPL + EHL) (according to
the example in Figure 4)
TAP = 115 psi (7.929 bar) – (7.49 psi (.516 bar) + 6.93 psi
(0.478 bar))
TAP = 115 psi (7.929 bar) – (14.42 psi (0.994 bar))
TAP = 100.58 psi (6.935 bar)
When the atomizer is located below the water piping outlet
on the system skid:
Total Atomizer Pressure (TAP) = 115 psi (7.929 bar) (pres-
sure available at outlet on skid) + (Elevation Head Loss
(EHL) – Total Pipe Pressure Loss (TPPL))
TAP = 115 psi (7.929 bar) – (TPPL – EHL)
For example, assume a system similar to Figure 4 in which
the atomizers are instead installed 12 ft (3.7 m) below the
water supply outlet. Then the TAP calculation would
proceed as follows:
TAP = 115 psi (7.929 bar) – (7.49 psi (.516 bar) - 6.93 psi
(0.478 bar))
TAP = 115 psi (7.929 bar) – (0.56 psi (0.039)
TAP = 114.44 psi (7.890 bar)