McQuay MCC-CW, Техническое руководство

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MFCU_(ii) Performance Data
58
Step 2
Step 3
As the unit is operating at 600m above sea level, the Altitude correction factor is 0.98 total and 0.93 sensible.
Step 4
Multiply the cooling capacities obtained from step 1 (as per specification and design condition) by correction
factors from (2) and (3)
Actual total cooling capacity = 11.7 x 1.0 x 0.98 kW = 11.47 kW
Actual sensible cooling capacity = 8.5 x 1.0 x 0.93 kW = 7.91 kW
Step 5
Water flow rate = Litres/M =
11470 W
= 32.8
70 x 5
Step 6
From Heating Capacity Performance Chart (Page 102) , determine the heating capacity at the nominal air
volume by using the flow rate calculated in step 5. The heating capacity is at 20.6 kW.
Step 7
From Heating Capacity Correction Factor Tables at 70°C water entering temperature and 26.7°C entering air
temperature, the correction factor is 1.1261,
Actual Heating Capacity= 20.6 x 0.98 x 1.1261 = 22.7 kW
Step 8
Water Pressure Drop can be estimated from water Pressure Drop Table (Page 33 to 39) using interpolate
method:
At flow rate of 32.8 Litres/Min, the nominal pressure drop is 39.14 kPa
Pressure drop correction factor = 1.2947 - 0.0021 x (EWT°C x 1.8 + 32) = 0.9629
Hence the actual pressure drop = nominal pressure drop x correction factor = 37.69 kPa.
MCK-AW
13.00
15.00
17.00
19.00
21.00
12.00 14.00 16.00 18.00 20.00 22.00 24.00 26.00 28.00 30.00 32.00 34.00 36.00 38.00 40.00
Water Flowrate - L/min
Heati
ng
C
apa
ci
ty
(k
W
)
ACK20AW
ACK25AW
ACK30AW
ACK40AW
ACK50AW
Refer to Page 40 to 42, the air flow correction factor at high speed is 1.0