Page 434 - Handbook of Energy Engineering Calculations

6. Make the pressure-drop calculation for the heat exchanger
Tubeside, Eq. (21):

Shellside, Eq. (25):
2
3
2
ΔP = (0.326/0.95)(32.8 )[12/(5 × 9)]= 3.9 Ib/in (26.9 kPa)
To decrease the pressure drop on the tubeside to the acceptable limit of 10
2
lb/in (68.9 kPa), the number of tubes must be increased. This will also
decrease the SOP. In addition, shellside performance can be improved by
decreasing the baffle spacing, since the pressure drop of 3.9 on the shellside
is lower than the allowable 10 psi (68.9 kPa). Before proceeding with

successive trials to balance the heat-transfer and pressure-drop restrictions.
Table 8 is now set up for clarity.

TABLE 8 Results of Trial Calculations