Nowadays, electricity has become essential in our lives
we use it in homes
communication
transports
and industries
but where does it come from?!
fossil fuel power plants are the primary source of electric power production
fossil fuel such as coal, are burnt to get steam
which then flows through turbines to generate electricity
but on the other hand
large amounts of dangerous gases are exhausted
and if not treated
the exhaust gases can have hazardous impacts on the planet
such as climate changes
acidic rain and other health issues
that’s why the world tends to use renewable energy sources
such as
 Solar energy
Geothermal energy
Hydropower
and Wind power, to generate electricity
installation capacity of wind farms
has increased thirty times over the last decade
various types of wind turbines are available in the market
turbines are classified according to Size
Main driving force
and the orientation of the axis of rotation
our target was to build a wind turbine
that is light weighted
can operate at low wind speed
have a compact size
and comes at a low price
among all the turbine types
ARCHIMEDES turbine was our best option
and now, we are going to see the whole story from start to finish
including all the working procedures and steps
the first step was the design process
our mission in mechanical design of ARCHIMEDES turbine
is to build a geometrical shape
which is simple and 3d printable
but before going into the designing process
some analytical considerations
and aerodynamic constrains
had to be given
so we collected data about the size
Geometry
and material of the turbine
from official technical papers
the design was made possible in a CAD software called SOLIDWORKS
by simply sweeping the blade profile along a fixed diameter helix
and removing any extras of the blade by revolve-cutting
Two ARCHIMEDES turbines were constructed
the first one is a constant angle design
where the blade angle does not change along the axis of the turbine
While the other one is a variable angle design
where the blade angle changes along the axis of the turbine
to be able to make experimental operations on the wind turbine
we needed a test rig
the test rig consists of the turbine
a small variable speed induction motor
and a torque sensor connecting them all on one shaft
building such a rig might seem as an easy task
but in practice
there are lots of factors that could make such a process a nightmare
Vibration
Misalignment
Mechanical friction
And unbalancing
are the main fears to expect when building such a rig
through a 5 month period of continuous work and problem solving
we were able to achieve a Stable
Balanced
Adjustable and low vibrating test rig setup
To know how efficient the wind turbine is
an experimental study has to be made
there are three parameters that indicate the turbine performance
these parameters are
The Torque coefficient
The Power coefficient
and The Tip speed ratio
to calculate these parameters
we have to get accurate measurement of the wind speed
Rotational speed of the wind turbine
and the torque developed by the turbine
after that MATLAB and Excel
are used to perform mathematical operations
to get the required parameters
To visualize and simulate wind flow and its effect on the turbine
We used ANSYS software
to perform a CFD study
CFD stands for computational fluid dynamics
and is used to validate experimental results
without any additional costs
this process consists of three main parts
Pre-processing
Solving
and Post-processing
in pre-processing
the geometry of the turbine
fluid domain construction
meshing and boundary conditions are installed
the next step
is solving
where equations and repeating iterations take place
and Finally, the post processing step
where the solution is analyzed and visualized to be displayed
