Page 450 - Handbook of Energy Engineering Calculations
P. 450
decreased. For the second trial, ¼ in (0.64 cm) spacing for both channels is
adopted.
Because the heat-transfer equation for every factor except the plate varies
directly with d , a new SOP can be calculated.
s
The new pressure drop becomes:
Hot side:
Cold side:
The pressure drops are less than the maximum allowable. The plate
spacing cannot be less than ¼ in (0.64 cm) for a 23.4-in (59.4-cm) plate
width; decreasing the width would result in a higher than allowable pressure
drop. Therefore, the design is acceptable.
6. Establish the final design of the spiral heat exchanger
The diameter of the outside spiral can now be calculated with Table 10 and
the following equation:
