Description
A cooling tower is a heat rejection device, which extracts waste
heat to the atmosphere though the cooling of a water stream to a
lower temperature. The type of heat rejection in a cooling tower is
termed "evaporative" in that it allows a small portion of the water
being cooled to evaporate into a moving air stream to provide
significant cooling to the rest of that water stream. The heat from
the water stream transferred to the air stream raises the air's
temperature and its relative humidity to **0%, and this air is
discharged to the atmosphere. Evaporative heat rejection devices
such as cooling towers are commonly used to provide significantly
lower water temperatures than achievable with "air cooled" or "dry"
heat rejection devices, like the radiator in a car, thereby
achieving more cost-effective and energy efficient operation of
systems in need of cooling. Think of the times you've seen
something hot be rapidly cooled by putting water on it, which
evaporates, cooling rapidly, such as an overheated car radiator.
The cooling potential of a wet surface is much better than a dry
one.
It is used for the cooling equipment in the line of metallurgy,
such as the medium
frequency induction furnace, melting furnace, steel smelting
furnace, casting, and rolling mill, etc. It is also used in the
cooling and dc in the line of spaceflight, electronic, instrument,
textile, injection, and electric power, etc.
