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Compressors, Pumps, and Turbines 223

Table 5.7 Continued

k j = f (chemical compound') — from Table 5.5 (5.7.23)

z,R"iY
v, = ———— (5.7.24)
Pi'
Variables

- Z - Z, - Z D - P 2 - P 3 - P 4 - PC - PC i - P CP - T C - T c i - PR, - PRD - T D - T R , - TRD -
W PN - W CN
k - k j - vj -V] - r\ T - n
Degrees of Freedom

F = 24 - 24 = 0

Table 5.8 Compressor Sizing Procedure__________________

1. Calculate T c, PC and k from Equations 5.7.18 to 5.7.23.

2. Calculate z, from Equations 5.7.12, 5.7.14, and 5.7.16.

ri P and (n - l)/n from Equations 5.7.7 to 5.7.9, and 5.7.24.
3. Calculate V ls v b
4. Assume one stage of compression (N = 1, P D = P 2).

5. Calculate W P[ from Equation 5.7.1.
6. Calculate the discharge temperature, T 2 (T D = T 2), from Equations 5.7.5 and
5.7.6.

7. If T 2 > Ira,*, assume two stages of compression (N = 2).

8. Calculate P 2 (P D = P4) from Equation 5.7.2.

9. Calculate W P2 from Equation 5.7.1.

10. Calculate the discharge temperature, T 4 (T D = T 4), from Equations 5.7.5 and
5.7.6.

11. Caculate the average compressibility factor z, from Eq. 5.7.11.

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