Analysis of the single zone system
|
—RA |
Tdb=72°F 0 = 50%
Q = 1.2xl06 Btn / h SHF = 0.8
Cooling
Coil
/
|
SA |
|
OA |
MA
Qcc
Cooling design conditions for OA are 16,262 cfm and 90°F db/72°F wb.
Design space cooling load is 1,200,000 Btu/h (80% sensible). Supply air temperature is 55°F. Determine (a) supply airflow rate and (b) cooling coil load.
Solution:
Plot known state on psych chart: OA, SA, and RA.
Assumption of perfect mixing => RA is equal to room air conditions => iRA=26.4 Btu/lbm
OA: iA=35.6 Btu/lbm, voa=14.1 ft3/lbm SA: iSA=21.2 Btu/lbm, vsa=13.1 fit3/lbm
(a) Flow rate O
(b) Cooling coil load O
Posted in Fundamentals of Heating. Ventilating, and Air-Conditioning