What is Evaporative Cooling
INTRODUCTION
1.1 Introduction
Evaporative
cooling or cooling through evaporation is a well-known natural occurrence. It
is just like that when the wind blows off the sea; it will lead the evaporation
of the water, so the temperature will be lower. When water evaporates from the
surface of something, that surface becomes much cooler because it requires heat
to change the liquid into the vapour.
 |
| Evaporative Cooling |
Fig 1.1 Natural evaporative cooling effects
For example, a
nice breeze on a hot day cools us because the current of air makes perspiration
evaporate quickly. The heat needed for this evaporation is taken from our own
body.
As air comes in
contact with water it absorbs it. The amount of water absorbed depends largely
on how much water is already in the air. The term humidity describes the level
of water in the air. When the air contains large amount of moisture, the
humidity is said to be high. If the air contains only a small amount of
moisture, the humidity is said to be low. When the air holds as much as
moisture as possible at certain temperature, the air is said to be
saturated. At saturation, the
temperature and the dew point are the same. The amount of humidity varies
according to the temperature and location. The warmer the air, the more
moisture, it is able to hold.
The amount of
water in the air compared to the amount required for saturation is called
relative humidity. If the air contains only half the amount of moisture it can
hold when saturated, the relative humidity is 50%.
Cooling by
evaporation has found many industrial applications. A rational development of a
combined cooling-tower heat exchanger unit is the evaporative fluid cooler and
evaporative condenser. In these heat exchangers, the purpose of the cooling
tower is to cool water, and of the heat exchanger, to cool the process fluid
using the cooled water, is merged. It is important to note that, with the
growth of the refrigeration and air conditioning industry, the evaporative cooler
came into extensive use, principally, as a refrigerant condenser.
 |
| Evaporative Cooling |
Fig 1.2 Combined schematic diagram of the Evaporative fluid cooler and
Evaporative condenser.
The
modeling of an evaporative cooler or condenser is complicated by the fact that three
fluids, normally flowing in different directions, interact with each other
through heat and mass transfer processes. Many modeling procedures, each with a
varying degree of approximation, can be found in the literature.
In the last 10
years, evaporative cooling technology for air conditioning systems has
increased as an alternative to the conventional vapor compression systems. An
evaporative cooling system operates using induced processes of heat and mass
transfer, where water and air are the working fluids. It consists,
specifically, in water evaporation, induced by the passage of an air flow, thus
decreasing the air temperature. When water evaporates into the air to be
cooled, simultaneously humidifying it, that is called Direct evaporative cooling (DEC)
and the thermal process is the adiabatic saturation. When the air to be cooled
is kept separated from the evaporation process, and therefore is not humidified
while it is cooled, it is called Indirect Evaporative Cooling (IEC).
This is only the introduction about evaporative cooling. I have uploaded everything about evaporative cooling to read them click here
If you want to go in more detail
Principle of evaporative cooling click here
If you want to go in more detail
Principle of evaporative cooling click here
To read about corona click here
Welcome to Factualtechy. We're dedicated to providing you the very best factual data that you want.
1 Comments:
Click here for CommentsNyc article ... knowledgeable too.
ConversionConversion EmoticonEmoticon