The wind turbine with a contour tracer supersedes horizontal
axis wind turbine (HAWT) by ability to deliver higher power for a
selected cross section, By reducing the manufacturing cost to 1/10th
compared to HAWT, ability to manufacture at site itself without sophisticated
part and simplicity in maintenance.
The author is able to design and build an amazing
vertical axis wind turbine that can deliver higher power than horizontal
axis wind power generator.
This wind
turbine with a contour tracer is having turbine blades spinning around
their own axis while orbiting around the central shaft vertically
positioned on a horizontal rigid basement. A pair of hubs is mounted
on bearings to the central shaft, positioned apart, over the central
shaft to hold the a symmetrically positioned plurality of extended
arms forming rotor framework outwards around the central shaft. Each
turbine blade is integrated with an extension of shaft projected down
words supported on pivots located on said extended arms of the said
rotor framework.
Down side of each turbine shaft is fitted with a crank
arm, providing leverage to hold a roller to paddle along the track
set on a horizontal platform disposed above the basement.
The crank arm is designed in such a manner that the rear side of
the rank arm is extended backwards so that a peg positioned on the
platform , be impelled on the rear extension of the crank arm in order
to turn the turbine on desired direction at the end of power stroke.
A horizontal platform is having over the basement and it is drivable
on bearings fitted to central shaft in order to adjust its orientation
to face the turbine blades along desired direction.
In operation, working cycle of each turbine blade is having a power
stroke and a return stroke. During power stroke turbine blades are turned
perpendicular to the direction of streaming wind whereas during the
return stroke turbine blades are turned along the direction of wind.
Concurrently, the turbine shafts are rotating about the central shaft,
while the turbine blades turning around the own axis.
The turbine blade direction is controlled by the contour traced by
the roller during power stroke.
In operation, the said roller engage with the contour track and paddle
between two guide walls of contour track, thereby turning the surface
of the turbine blade perpendicular to wind direction and maintaining
its direction during the first half circle of movement of the turbine
blade. When the turbine blade moves to the extreme end, the contour
track releases engagement of the roller thereby allows the turbine
blade move freely. Then the turbine blade turns along streaming wind
direction and produce minimum air resistance during its return stroke
until it propel back on the other way round to the starting position.
Thus another cycle continues by the roller engagement with the contour
track.
The turning movement of the rotor geared to electricity power generator
to produce usable electricity.
Further, a break system and controls are accompanied to stop or reduce
the rotational speed of the rotor and turbine blades.
For best performance number of turbine blades should be two or three.
This wind turbine is low cost high efficient easy to assemble and
build product. Its blades cover much larger area than a circular profile
of the space of streaming wind. Power generator and control equipment
are installed on ground level and reduces maintenance cost procedures.
It can build to greater height.
The turbine blades are having flat surface, sothat
the cost of manufacturing turbine blades and transporting them to
instaling ground has become economical.
Impulse turbines change the direction
of flow of fluid stream. In reaction turbines air flow pass through
the moving blades. Betz law applies for the wind flow that passes
through a reaction turbine. But this wind turbine behave as an impulse
turbine.
A guide parth for crank pin can be designed for the
complete revolution. (You may note that the crank arm is able to turn
at desired direction when the turbine blade moves to the extreme end,
the rear side of the rank arm is extended backwards so that a peg
positioned on the platform , be impelled on the rear extension of
the crank arm in order to turn the turbine blade on desired direction
at the end of power stroke.)
Further the direction of each turbine blade can control
by servomotors or stepper motors with or without using the guide path.
Power generating ability compared to horizontal axis
wind turbine is analyzed here