Page 329 - HVAC Pump Handbook

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Open Cooling Tower Pumps

326 Pumps for Open HVAC Cooling Systems

minute with a specific temperature difference between inlet and out-
let temperatures.
A detailed description of cooling tower performance is beyond the
scope of this book. This chapter will be devoted to the piping and pump-
ing of cooling towers and chiller condensers and how their performance
affects cooling tower pumps and vice versa. The next chapter will deal
with process cooling using cooling towers and other equipment.
For a detailed description of the thermodynamics of cooling towers
and a comprehensive discussion of the various types of cooling towers,
the reader is encouraged to study Cooling Tower (Chap. 36 of the
Systems and Equipment volume of the ASHRAE Handbook for
Heating, Ventilating and Air-Conditioning, 2004.
Obviously, there are a number of different arrangements of cooling
tower fill and air patterns to achieve the most efficient and economi-
cally feasible cooling tower for the many different sizes and types of
HVAC and industrial installations. Table 11.1 is a general graphic
representation of the type of towers currently being used in these
industries. Basically, a cooling tower is simply a container in which
water and air both flow together. Most often the airflow is either
forced (pushed) or drawn (pulled) through falling water. Usually, the

TABLE 11.1 Classification of Open Cooling Towers
SPARY TYPE
NATURAL COUNTERFLOW
DRAFT
HYPERBOLIC
CROSSFLOW

COOLING
TOWERS

FORCED
DRAFT
COUNTERFLOW SINGLE FLOW
MECHANICAL
CROSSFLOW
DRAFT
INDUCED
DRAFT DOUBLE FLOW
COUNTERFLOW

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