Wind Harvesting System.

1. National Design League
Capturing the wind
moving around a
subway
Team Rhythm

2. Team Information
McMaster University
Team Rhythm
Number # 22
Members:
• HamzahMaklai
• Maaz Khan
• Rajdeep Rana
• Asad Irfan
Date: October 25th, 2020

3. How is Wind Energy Harvested?
• Wind turbine blades capture the energy in the wind by slowing down wind
velocity.
• A gearbox is used to increase the turbine rotor speed to higher speed suitable for
the generator.
• The rotary axis is attached to an electric power generator from either front end or
back end, which allows the turbine to transfer the collected energy into usable
power.

4. Team Strategy

5. Identification
• Problem Statement: When subway trains travel at high speeds, they
cause the air around them to move at high speeds as well. This
tremendous amount of kinetic energy is currently going to waste.
• Objective: The primary objective of this project is to harvest the
kinetic energy from the air around subways when they travel at high
speeds.
• Requirements and Constraints: Consider safety hazards and
precautions, maintenance, cost, and overall feasibility.

6. Considerations
• Piston Effect
• Must assess forced air flow
• Forced air due to train moving in tunnel
• In theory, wind generated from train would
be moving at a slower speed than the train
as can be shown in the following graph
• Location Testing
• Would need to test locations for top speeds
in subway routes, to place turbines in
optimal locations to capture wind with
highest kinetic energy
• Material
• Which material would have the least drag?
• Which material would fatigue slower?
• Safety Testing
• How would the pressure inside the tunnel
affect the performance of the material?
• Making sure dimensions allow for safe
travel, objects do not collide

7. Research
• Small wind turbines are installed closer to
urban areas improving the opportunity
for off-grid urban equipment
• They are distinguished by either lift or
drag configurations depending on the
effective aerodynamic force that rotates
the wind turbine.
• We want to provide an improved
horizontal axis fluid turbine that is
effective in generating power while at the
same time: is simple, safe, inexpensive to
construct& maintain.

8. Turbine Design
• Our inspiration for the design was
drawn from the Archimedes Turbine
• It includes a plurality of blades
mounted symmetrically along the axis
of rotation in a spiral shape.
• Each blade consists of a logarithmic
curve pattern with a certain curve
radius and is placed around a rotary
axis
• Unlike other turbines with a central
hub in the middle, our blades are
relatively parallel to fluid flow
direction for better stability.
• This is more effective in trapping air
than the conventional three-blade
propeller since it exposes more blade
surface, resulting in a larger swept
area, giving high rpm.

9. Turbine Assembly
• The turbine assembly consistsof the blade,
brake, gearbox and generator
• The design was made possible using
Autodesk Inventor 2021
• By sweeping the blade profile along a fixed
diameter helix, and removing extras using
revolve cutting we were able to constructa
variable angle turbine (The blade angle
changes along the axis of the turbine)

10. How will it work?
• The turbines will be arranged in rows of three along sections of the subway tunnel
where the velocity of the train is at its max and wind speed is sufficient
• The fluid wind current traveling through the logarithmic turbine is diverted
gradually from its original straight flow direction into a spiral, causing it to travel a
longer distance, resulting in increased fluid velocity inside the logarithmic turbine
which helps increasing the angular velocity of the turbine(rpm) and turn the shaft.
• Having the leading edge parallel to the flow direction of fluid will ensure that the
logarithmic turbine is efficient in its functionality of gathering kinetic energy.

11. Design Application
• These are section views of how the turbines will be
placed
• Three turbines are seated in a landing on the top of the
tunnel
• There is enough clearance between the turbines and the
wall

12. Front and Back images showing the
placement of the turbines with respect
to the tunnel and the train

13. Dimensions
• Train height and width
• Tunnel height and width
• Turbine housing height and
clearance
(All units are in meters)

14. CFD analysis
• Generated using SolidWorks
• Avg Wind Speed = 2.2m/s
• Rotation = 650 rpm

15. Output
• The Average wind speed in the tunnel is 2.2 m/s.
• From extensive research on experimental data regarding the Archimedes Spiral wind turbine, we
conclude that the design provides an input angular speed of 650 rpm. (68.07rad/s)
• To generate electricity using a motor, the average rotation speed required as an input is between
1800-2600 rpm.
• We use a simple gear train with a ratio of 1:4 to increase our input to the motor.
• EstimatedPower Output ~620 KWH/Year
Gear Number of Teeth Connection Type Speed on gear
1 24 Axiallywith Turbine 650 rpm
2 12 Mesh 1300 rpm
3 24 Axial 1300 rpm
4 12 Mesh 2600 rpm

16. Safety
• There is enough clearance between the turbines, train and the tunnel walls,
eliminating the possibility of a collision.
• Our housing bracket also includes an outlet for wind to pass through, ensuring no
turbulent forces are generated, allowing the turbines to spin in one direction.
• Each turbine has a brake attached that will automatically stop operations if there is
any disturbance
Front View Back View

17. Material Selection
• Following a research study that used
the BELO method we were able to
select our optimum material.
• BELO uses material properties from
the existing wind turbine blade and
instead of adding or removing
material to and from the structure,
the algorithm rearranges the type
and lay of the composite location
within the structureuntil no
significant change in the overall
strain energy of the blade is
observed.

18. • Our blades are composite-constructed, with a fiberglass outer shell
and a foam core.
• This will reduce blade mass inertia, allowing the blades to accelerate
more rapidly during start-up leading to increased power production
without compromising the blades structural performance or
longevity.

19. Maintenance
• As the turbines are individually installed into the housing, maintenance workers
have easy access to damaged/faulty turbines. Entire Component can ‘slide out’.
• Existing track maintenance periods can be used to repair such turbines, which
eliminates the need for turbine-only shutdowns, which can lead to losses in
revenue.
• There is enough clearance between the turbines, the tunnel walls and the train
track which would allow workers to comfortably walk on the sides to carry out
routine check-ups.

20. Finances
• We have included a rough financial model
of what the expected cost of partially
implementing this system.
• It is missing several factors like
Government fees and certifications,
Infrastructure development, R & D costs
etc. that will heavily influence the pilot
phase.
• Link to Editable .xlsx – FinanceModel.xlsx

21. Outcomes
Pros Cons
Source of Clean Energy Costly Pilot phase includinginstallation and
manufacturing
No aesthetic / acoustic issues Increased station& track maintenancetimes
Space efficiency (utilizes existing space) Current conditionof stationmight affect cost of
installation
Helps Wind Energy become more cost effective Localized impact on stationtemperature
Utilizes existing track & stationmaintenanceperiods
Distributionlevel transmission integration
Electricity generated can be used to power subway
stations
Can take advantageof Ontario’shigh wind energy
subsidies and numeroustransit lines

22. References
• https://www.rees-journal.org/articles/rees/pdf/2017/01/rees170006s.pdf
• https://en.wikipedia.org/wiki/Small_wind_turbine
• https://thesource.metro.net/2014/03/31/metro-explores-new-green-energy/
• https://spiralairfoil.weebly.com/specs.html
• https://www.google.com/search?q=Archimedes+wind+turbines&oq=Archimedes+wind+turbines&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8
• https://patentimages.storage.googleapis.com/01/b0/39/b86d36ffa22f98/US20120076656A1.pdf
• file:///C:/Users/hamza/Downloads/Analysis_of_Archimedes_Spiral_Wind_Turbine_Perform.pdf
• http://www.polyumac.com/upload/files/GatorBoard+Info+and+Data+Sheet+Nov+26+2019.pdf