The Basic Principle of Refrigerators (Part 1)
Daftar Isi
The basic principle of
refrigerators is simple. Simply pass a colder liquid continuously around the
object to be cool. Let's see how this continuous called liquid flow is achieved
inside a refrigerator. A simple device called a throttling device is the most
crucial component of refrigerators. What is used as throttling device a cold
liquid is produced using the throttling phenomenon. Or if I do the throttling
at the inlet the refrigerant should be at a liquid state under high
pressure.
Throttling device has an
obstruction to the flow so huge pressure drop occurs when the liquid flows
through it. As the pressure drops the boiling point of a liquid comes down.
Does the refrigerant liquid evaporates. The energy required for such a
vibration comes from the refrigerant so it's temperature drops. You will notice
this drop when you check the temperature across the throttling device.
Please note that only a
portion of the refrigerant is evaporated here. This is ones important property
of the refrigeration fluid. It should be able to change the phase while varying
the pressure under normal temperature. The next phase is simple just passed
this cold liquid over the body which is to be cooled. The refrigerant further
evaporates and transforms into pure vapor during the heat absorption process.
Since there is phase change during this process the refrigerant temperature
does not increase this heat exchanger is called the evaporator.
With the help of clever
air flow circulation inside the refrigerator using an evaporator fan one can
maintain different temperature levels. So we have produced the required
refrigeration effect if we could take this low-pressure refrigerant to the
state before throttling that is high pressure liquid we will be able to repeat
this process. So the first step is to raise the pressure. A compressor is used
for this purpose.
The compressor will
raise the pressure back to its initial value. You can see that a reciprocating
type compressor is used here. However since it is compressing gas along with
pressure the temperature will also increase. This is unavoidable. Now the
refrigerant is high pressure vapor.
To convert it to a
liquid stage we introduce another heat exchanger. This
heat exchanger is fitted outside of the refrigerator. It will liberate heat to
its surroundings vapor will be converted to liquid and temperature will reach a
normal level this heat exchanger is known as a condenser. Now the refrigerant
is back to its initial stayed so we could be fed to the throttling device
again. Just by repeating the cycle over and over we will be able to achieve a
continuous cooling effect. Who is more specifically called the vapor
compression cycle.
Posting Komentar