Rapid 4044, Инструкция по установке, эксплуатации и обслуживанию

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4000-S
ERIES
I
NSTALLATION
, O
PERATION AND
S
ERVICE
M
ANUAL
68 of 154
SECTION 16: COOLING SPECIFICATIONS
16.1 Evaporative Coolin
g
Table 21: Formulas
* Bleed-off and recirc u lation rates w ill v ary w ith
locale, w ater q u ality and chemical treatment
program. These v al u es are only for approximation.
NOTE: Refer to sat u ration efficiency table belo w .
Table 22: Abbreviations
Table 23: Evaporation Rate
• Heat of v aporization = 1043 BTU/lb
• Weight of w ater = 8.34 lb./Gallon
• GPH = CFM x WBD x SE x 1.08/1043/8.34 = CFM x WBD x SE/8050
Table 24: Su gg ested Air Chan g es Per Hour (Air
Chan g e Method)
* For existing b u ildings: A v erage amo u nt indoor
temperat u re exceeds ambient o u tdoor temperat u re
w hen e v aporati v e cooling is not in u se.
** Experience has sho w n that significant benefit can
be achie v ed w ith 10-15 Air Changes per Ho u r (AC/
Hr) thro u gh the lo w est 12' of the facility. For a 24'
high b u ilding, this w o u ld mean 5-6 Air Changes per
Ho u r (AC/Hr) for the entire v ol u me. This w ill v ary by
application.
Table 25: Saturation Efficiency at Stated Media
Depth
Table 26: Static Pressure Drop (in wc) at Stated
Media Depth
NOTE: Moist u re limiter press u re drop is added for
face v elocities greater than 600 Feet per Min u te
(FPM). Rapid Engineering LLC's standard media
thickness eq
u als 12".
Formulas
1 Lea v ing Dry B u lb = ODB – [SE* x (ODB - OWB)]
2
Lea v ing Wet B u lb = Entering Wet B u lb (act u ally, it’s slightly less
than the entering w et b u lb, b u t is normally considered eq u al.)
3 Wet B u lb Depression = ODB – OWB
4 E v aporation Rate (GPH) = CFM x WBD x SE/8050
5 Bleed-off Rate = approximately 20% of e v aporation rate*
6 Recirc u lation Rate = approximately 3 times e v aporation rate*
Abbreviations
CFM C u bic Feet Per Min u te
GPH Gallons Per Ho u r
IDB Indoor (Design) Dry B u lb Temperat u re
LDB Lea v ing Dry B u lb Temperat u re
LWB Lea v ing Wet B u lb Temperat u re
ODB O u tdoor (Design) Dry B u lb Temperat u re
OWB O u tdoor (Design) Wet B u lb Temperat u re
SE Sat u ration Efficiency of the E v aporati v e Media
WBD Wet B u lb Depression
Wet Bulb
Depression (°F)
Gallons per Hour (GPH) Per 1,000 Cubic Feet per Minute (CFM) at Stated Saturation Efficiency
0. 8 0 0. 8 2 0. 8 4 0. 8 6 0. 88 0.90 0.92 0.94 0.96 0.9 8
5 0.50 0.51 0.52 0.53 0.55 0.56 0.57 0.58 0.60 0.61
10 0.99 1.02 1.04 1.07 1.09 1.12 1.14 1.17 1.19 1.22
15 1.49 1.53 1.56 1.60 1.64 1.68 1.71 1.75 1.79 1.83
20 1.99 2.04 2.09 2.14 2.19 2.23 2.28 2.33 2.38 2.43
25 2.48 2.55 2.61 2.67 2.73 2.79 2.86 2.92 2.98 3.04
30 2.98 3.05 3.13 3.20 3.28 3.35 3.43 3.50 3.58 3.65
35 3.48 3.56 3.65 3.74 3.82 3.91 4.00 4.08 4.17 4.26
40 3.97 4.07 4.17 4.27 4.37 4.47 4.57 4.67 4.77 4.87
45 4.47 4.58 4.69 4.80 4.92 5.03 5.14 5.25 5.36 5.48
Leavin g Air
Temperature
(°F DB)
Indoor Air
Temperature Above
Ambient (°F)*
Air Chan g es/Hour**
78° 20° 30 - 60
76° - 78° 15° - 20° 20 - 40
74° - 76° 10° - 15° 15 - 30
72° - 74° 5° - 15° 12 - 20
< 72° < 10° 10 - 15
Airflow
Feet per
Minute (FPM)
6" 8 " 12" 1 8 " 24"
400 0.71 0.81 0.90 0.98 0.99
500 0.68 0.79 0.89 0.98 0.99
600 0.66 0.77 0.88 0.97 0.99
700 0.64 0.75 0.87 0.97 0.98
Airflow
Feet per
Minute (FPM)
6" 8 " 12" 1 8 " 24"
400 0.06 0.09 0.14 0.19 0.24
500 0.09 0.14 0.21 0.30 0.39
600 0.13 0.20 0.30 0.42 0.55
700 0.23 0.31 0.44 0.62 0.80