An alternate design of this type of tower uses packing (or fill) with an open
design. Splashboards, triangular PVC rods, or an open polyethylene design are
among the several possibilities for the fill design. The basic purpose of these various
fills is the same: to increase water/air contact surface with minimum added resistance
to both air and water flows.
With the exception of large, hyperbolic cooling towers that are a special case
(such as those in Fig. 5.3), this type of cooling tower is normally used for smaller
installations such as hospitals, office buildings, or other relatively small facilities.
This type of cooling tower is the typical of refrigeration units.
Fan Assis: Counterflow
Induced Draft
Air
Inlet
Air
Inlet
Air Outlet
Fan
Fig. 5.9 Fan assist (draft or
mechanical type) counterflow induced draft cooling
tower
Fan Assist Crossflow
Induced Draft
Air
Inlet
Air
Inlet
Air Outlet
Fan
Fill
Fill
Fig. 5.10 Fan assist
(induced or mechanical
type) cross-flow induced
draft cooling tower
216
Y.-T. Hung et al.