Chapter hvac engineering Fundamentals: Part 1 Introduction

19.5.4
Adiabatic saturation
If an airstream is passed through a water spray (Fig. 19.6) in such a
way that the leaving air is saturated adiabatically, then the process
can be shown on the chart as a constant-wet-bulb process (Fig. 19.7),
and the final wet- and dry-bulb temperatures are equal. In practice,
this process is called
evaporative cooling,
and saturation is not
achieved (Fig. 19.8). The
efficiency,
denoted eff, of an air washer or
evaporative cooler is the ratio of the dry-bulb temperature difference
from point 1 to point 2 to the initial difference between the dry- and
wet-bulb temperatures:
Engineering Fundamentals: Part 4
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