Page 455 - Handbook of Energy Engineering Calculations

columns in Table 9 tabulate the numerical, physical-property, work, and
mechanical-design factors—all of which together form the recast dimensional
equation. The product of these factors gives the fraction of total temperature
drop or driving force (ΔT /ΔT ) across the resistance.
f
M
As stated, the sum of ΔT /ΔT (the hot-fluid factor), ΔT /ΔT (the cold-
c
M
h
M
fluid factor), ΔT /ΔT (the fouling factor), and ΔT /ΔT (the plate factor)
s
M
w
M
determines the adequacy of heat transfer. Any combinations of ΔT /ΔT may
f
M
be used, as long as the orientation specified by the equation matches that of
the exchanger’s flow path.
The units in the pressure-drop equations are consistent with those used for
heat transfer. Pressure drop is calculated directly in psi.
This procedure is the work of Paul E. Minton, Project Engineer,
Engineering Department, Union Carbide Corporation, as reported in
Chemical Engineering magazine. SI values were added by the handbook
editor.