A
centrifugal compressor is one of the compressors
that is used in jet aircraft. A centrifugal compressor
raises the pressure of the air by imparting velocity
energy, using a rotary impeller and converting
it to compressed air. A centrifugal compressor
is also called a radial compressor. It consists
of two alternating sets of rotating blades enclosed
within a casing. .
How
does it work?
Each blade on a centrifugal compressor produces
a pressure variation similar to that of a propeller.
The blades are closer together than in a propeller
and this changes the flow between the blades.
Centrifugal compressors work on this airflow
by turning it rapidly and accelerating it.
Where are Centrifugal Compressors found?
Centrifugal compressors are found in large industrial
settings and on aircraft. They have very few
moving parts that can break down, thus cutting
down on the maintenance costs involved in repair.
They are very energy efficient and are better
for larger settings than reciprocal compressors
because they give a higher airflow. They are
best suited to continuous duty applications such
as ventilation fans, air movers, and cooling
units where high volumes of air are required
at low pressures. Although a centrifugal air
compressor can work in reverse, the efficiency
is reduced because of the design of the blade.
Very large centrifugal compressors are used
in gas pipelines all over the world for transporting
the gas. They do, however, have operating limits
when used in this capacity. There is a minimum
allowable speed and a maximum allowable speed
to maintain continuous operation. Going over
the maximum speed is very dangerous, especially
when dealing with oil and gas.
Problems with a centrifugal air compressor
A
centrifugal air compressor is deigned to be
oil free. They are deigned to handle a base or
continuous load. A common problem that can occur
with centrifugal compressors is called surge.
This happens when the compressor is throttled
below 70% of its maximum capacity. It is usually
associated with a reversal of airflow back into
the compressor when it is unable to maintain
a steady flow of air. This can cause excessive
vibration and mechanical damage in a very short
time. Because
of their scope and size, you would not need to
have a centrifugal compressor in your
home.
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