Page 452 - Handbook of Energy Engineering Calculations

Related Calculations. Spiral heat exchangers have a number of advantages
over conventional shell-and-tube exchangers: centrifugal forces increase heat
transfer; the compact configuration results in a shorter undisturbed flow

length; relatively easy cleaning; and resistance to fouling. These curved-flow
units (spiral plate and spiral tube) are particularly useful for handling viscous
or solids-containing fluids.

A spiral-plate exchanger is fabricated from two relatively long strips of
plate, which are spaced apart and wound around an open, split center to form
a pair of concentric spiral passages. Spacing is maintained uniformly along
the length of the spiral by spacer studs welded to the plates.
For most services, both fluid-flow channels are closed by alternate

channels welded at both sides of the spiral plate (Fig. 13). In some
applications, one of the channels is left completely open (Fig. d), the other
closed at both sides of the plate. These two types of construction prevent the

fluids from mixing.