FOR FUTURE ENERGY
Inventor = Robert Stirling
(1790 - 1878)
Sought to replace the
steam turbines of his days
due to frequent explosion
caused by unsustainable
high pressure killing and
Invented Stirling engine in
1816 which could not
explode and produce more
power then th steam
WHAT IS STIRLING ENGINE ?
Device that converts heat energy to mechanical power by
alternately compressing and expanding a fixed quantity of
working fluid at different temperatures.
Regeneration as alternative.
WHY STIRLING ENGINE?
Best teaching and learning for any engineering students device
especially in the field of thermodynamics.
An innovation with hundreds of application.
An innovation with a mission to save the earth.
Power piston – small tightly sealed piston that moves up when
the gas inside the engine expands
Displacer – larger piston and it is very loose in its cylinder so air
can move easily between the heated cooled sections of the
engine as the displacer moves up and down
These piston move by the action of compression and expansion.
Difference in pressure causes the piston to move and produce
One side of the engine is continuously heated while the other
side is continuously cooled.
II. First, the air moves to the hot side, where it is heated and it
expands pushing up on a piston.
III. Then the air moves through the regenerator to the cold side,
where it cools off and contracts pulling down on the piston.
IV. Temperature change inside the engine produces the pressure
change needed to push on the piston and make the engine
Stirling engine efficiency = Carnot efficiency
Unfortunately working fluid or gas is not ideal this causes the
efficiency to be lower than Carnot efficiency.
In fact, Stirling engine efficiency depends on
Temperature ratio (proportionally)
Pressure ratio (inversely proportional)
Specific heat ratio (inversely proportional)
Various heat sources (solar, geothermal, nuclear energy, waste
Heat is external and the burning of a fuel-air mixture can be
more accurately controlled.
Operates at relatively low pressure and thus are much safer
than typical steam turbines
Less manpower needed to operate any type of commercial
Water pump stations
Combined heat and power plant
Solar power generation
WATER PUMP STATION
A Stirling engine used for pumping
water can be configured so that the
water cools the compression space.
This is most effective when pumping
Any Stirling engine will also work in reverse as a heat pump.
When a motion is applied to the shaft, a temperature difference
appears between the reservoirs.
Replacing the steam turbines of the nuclear power plant with
Stirling engine might simplify the plant, yield greater efficiency,
and reduce the radioactivity by products.
Unlimited source of heat source
Political awareness of green heat and power production.
Large market experiencing rapid growth.
Many different possible applications.
Time to change.