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Process Circuit Analysis 103

Table 3.2.1 Summary of Equations for Calculating Cooling-Tower Air
Flow Rate___________________________________

Subscripts: H 2O = 1, Air = 2

Mole Balances
y,,i m, + m 3' = y v m 2 + nx, (3.2.1)

y\,2 rri] = y 2>2 rn 2 (3.2.2)

yi,i+y.,2=l (3.2.3)
y 2,i + y 2,2 = i (3.2.4)

Energy Balance
H! m] + h 3 m 3'= h 2 m 2 + h 4 m, (3.2.5)

Transport Relation

Vi.i = f(W, Viw, Ah vw) (3.2.6)
Equilibrium Relations

y 2 ,i=0-9p2,is/P' (3.2.7)

Xiw = Piw/P' (3-2.8)
Thermodynamic Properties

p = f(ti') — steam tables (3.2.9)
w w
Ahvw = ffW) — steam tables (3.2.10)
pi = f(t) — steam tables (3.2.11)
2) S 2
(3-2.12)
(3.2.13)

h u =f(t,') (3.2.14)

h,.2 = f[ti') (3.2.15)
hy = f(t2) (3.2.16)

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