PELTON TURBINE
Defination
Pelton Wheel Turbine is
the type of impulse or hydraulic turbine which is used for high heads for the
generation of power. It was invented by American inventor Lester Allan
Pelton in the 1870s.
Working principle
The working principle is
water is coming from the storage reservoir through a penstock to the Inlet of
the nozzle which is the inlet of the turbine so the hydraulic energy of the
water is mainly converted into kinetic energy. As the jet strikes over the
runner vane, it will apply a large magnitude force for a small amount of time
over the runner called Pelton force the Pelton force will rotate the rotor.
Pelton Wheel Turbine Construction or Parts:
The
following construction or parts of Pelton wheel Turbine:
·
Casing
·
Spear
·
Break Nozzle
·
Runner or Rotor
·
Penstock
·
Governing
Mechanism
Casing :
The Pelton wheel casing prevents the
splashing of water and it also act as the protecting cover for turbine .
Spear:
Needle Spear will control the water flow
and it moves insides the nozzle and provides smooth flow so there can be very
less energy loss. Spear is used to control the rate of flow of water that will
strike on turbine blade .
Break Nozzle:
The runner rotates even after closing the nozzle due to
inertia.To stop the runner to rest in a short time a breaking jet is provided
which directs the water on the bucket in the opposite direction . this is
called breaking jet.
Runner or Rotor:
The runner of a Pelton turbine basically consists of a disk with a number of buckets
attached along its periphery .The high speed water jet impinges
the buckets perpendicularly so that maximum torque is applied to the rotor.
Penstock:
A penstock is a gate or intake structure that controls
water flow, or an enclosed pipe that delivers water to hydro turbines and
sewerage systems
Pelton Wheel Turbine Advantages:
The
following adavnatages of Pelton Turbine are:
·
The Pelton Turbine simple in design and
also the construction is not complex.
·
The water which is clean cannot cause
very rapid wear in high heads.
·
The overhaul and inspection are much
easier than another turbine.
·
The overall efficiency is quite high as
compared to reaction turbines.
·
There is no requirement for the draft
tube here.
·
In the Hydraulic Turbine, it
is the most efficient turbine.
·
The parts assemble of the Pelton turbine
is very easy. No complexity here.
·
The water striking and leaving the runner
at atmospheric pressure only.
·
This is a tangential flow turbine. It can
move in axial flow or radial flow direction
Pelton Wheel Turbine Disadvantages:
·
The mechanical efficiency of the Pelton
wheel decreases faster compare to the Francis turbine.
·
The size of the runner, generator,
powerhouse required is large and not economical if the Pelton turbine is used
instead of the Francis turbine for the same power generation.
Pelton Wheel Turbine
Application:
The
following application of Pelton Wheel Turbine is:
·
The Pelton Turbine wheel turbine is used
in Hydro Power Plant where Less discharge and High Heads are
required.
·
This is used to get more velocity of the
fluid for maximum power and efficiency [Because the turbine and
wheel are designed in such a way that the water jet velocity is twice the
rotating bucket velocity].
·
It is also used to drive the generator
and who is attached to the turbine shaft here the Mechanical energy gets
converted into Electrical Energy.
Post a Comment