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Notes - Wind Turbine ISR-G (view source)
Revision as of 22:50, 16 January 2021
, 22:50, 16 January 2021no edit summary
These are notes for my wind turbine independent study with Jeff Dusek.
##11/12/2020
### Tower design
[[File:Wooden-tower-2.JPG|border|thumb|potential design: 6x6s with cross beams]]
A tower design with four pressure-treated 4x4s or 6x6s that are connected via diagonal crossbeams on the outside and plateaus seem reasonable.
On this [website](https://www.rockridgewindmills.com/photo-video-gallery/new-windmill-projects/big-wood-tower/) you can find some inspiring images.
[[File:Tower-design-v1.JPG|300px]]
### Small Scale Wind Turbines Optimized for Low Wind Speeds
Letcher, T. (2010). [Small scale wind turbines optimized for Low Wind Speeds](https://drive.google.com/file/d/1ZQyqHlQZY_gyVylVg2PHsEZCPJwZ3cGe/view?usp=sharing).
### 10 Wind Turbines That Push the Limits of Design
https://www.popularmechanics.com/science/energy/a4428/4324331/
### Design and Manufacture of a Cross-Flow Helical Tidal Turbine
Anderson, J., Hughes, B., Johnson, C., Stelzenmuller, N., Sutanto, L., & Taylor, B. (2011). [Capstone Project Report: Design and Manufacture of a Cross-flow Helical Tidal Turbine](https://drive.google.com/file/d/110NNrJwMsjzH_Jbfal9jF5kHzRMOwEfB/view?usp=sharing). University of Washington, Washington.
##11/05/2020
### up next
- think about Gorlov blade design - [Onix 1 3D printer](https://markforged.com/3d-printers/onyx-one) - prints with carbon embedded - build volume 320 x 132 mm 154mm tall
- scale down based on reynolds number - relevant dimension: qart of the foil, dynamic viscosity [paper](https://asmedigitalcollection.asme.org/energyresources/article-abstract/137/5/051208/372961/Small-Scale-Wind-Turbine-Testing-in-Wind-Tunnels?redirectedFrom=fulltext)
- look into motor shaft sealing water - propellor shaft seals - drive shaft seal
- https://wes.copernicus.org/preprints/wes-2020-66/wes-2020-66.pdf
- final deliverable
- tower design
- email STI files to Tim or Daniela
### Newly structured wiki page for wind turbine system
All research insights, prototyping steps, and other system information is documented in [[Wind turbine system]].
### Twisted Savonius V1
[[File:CAD-v1-savonius.png|border|thumb|CAD of twisted Savonius prototype]]
[[File:Savonius-prototype-v1.jpg|border|thumb|V1 of twisted Savonius prototype]]
We attempted to prototype a twisted Savonius turbine to allow a more continuous application of force when the wind turbine spins. Ideally, both sails would be slightly offset to each other to allow airflow from one airfoil to the other. Such an offset can be seen in the following picture that inspired our design. As the Savonius turbine is based on drag, it has a high starting torque, which will allow for lower self-starting speeds.
[[File:Savonius-twisted-airfoil.png|frameless|border|]]
With our next prototype, we seek to combine a twisted Savonius turbine with a Gorlov turbine (Rajdeep Nath Dr. John Rajan; How to Design and Fabricate a Vertical Axis Wind Turbine: Design, Analysis, and Fabrication using Gorlov and Savonius Blades (p. 75)). We can 3D print the blades but might want to scale down the prototype to decrease printing time.
[[File:Savonius-gorlov-waterpump.jpeg|frameless|border|]]
### How to charge our batteries
We seek to charge our battery system with the energy obtained from the wind turbine. However, our current system diagram connects the AC rectifier to the inverter, which outputs 110 V alternating current (US outlets). As the energy output from the wind turbine will vary quite a lot, we need to charge the batteries with direct current (DC). For that purpose, we might have to acquire a wind turbine battery charge controller that can handle high voltages (0-600 V from the AC rectifier) to charge our 24 V battery system. Tae Chang offers a [Battery Charge Controller](https://tcnet.en.ec21.com/Battery_Charger_Controller--1105310_1105320.html). We probably need a _600 VDC 24v wind turbine MPPT charge controller 2500W_. Most charge controllers seem to be in the range of 200-300 VDC ([example](https://www.grainger.com/product/55HX52?cm_mmc=PPC:+Google+PLA&ef_id=CjwKCAiA4o79BRBvEiwAjteoYOv_peCpu8ur8vgakfuuD9tEog_f5FFEEgu7gsxPleKhCmGqSbyKoRoCkEUQAvD_BwE:G:s&s_kwcid=AL!2966!3!264955915673!!!g!461787465034!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=CjwKCAiA4o79BRBvEiwAjteoYOv_peCpu8ur8vgakfuuD9tEog_f5FFEEgu7gsxPleKhCmGqSbyKoRoCkEUQAvD_BwE)), which might be enough considering wind speeds in our area.
## Tower design
We considering building a wooden structure on top of the house to elevate the wind turbine. A tripod design that attaches to the two bump-outs and the gable would make the tower accessible. We are currently considering a tower height of 15 feet up to 22 feet.
[[File:Anemometer-house.jpeg|border|thumb|The tower could be mounted in between the two bump outs]]
Guy wires are an option to secure the turbine as it will be quite large to account for low wind speeds. However, a pole that is merely held up by guy wires is not accessible enough.
##10/29/2020
### Materials - stress and strain
[[File:Aerodynamic-load-wind-turbine.JPG|border|thumb|]]
[[File:Stress-strain.JPG|border|thumb|]]
### Forces on VAWT
[[File:ForcesOnVAWTairfoil.JPG|border|thumb|Vector diagram of the aerodynamic forces acting on a VAWT airfoil. Here U is the freestream velocity, ω is the angular velocity of the turbine, R is the turbine radius, Urel is the relative freestream velocity as seen by the turbine blade, and Ft(lift) and Ft(drag) are the tangential components of the lift and drag forces, i.e., Flift and Fdrag, respectively.<ref>Araya, D. B. (2016). Aerodynamics of vertical-axis wind turbines in full-scale and laboratory-scale experiments (Doctoral dissertation, California Institute of Technology).</ref>]]
### Meeting at Farm - Agenda
- where does everyone's interest lie?
- go over the system diagram and questions
- what are our resources? Whom do you know? - Dylan and maybe folks from Appalachian State University
- look at to-dos
- find a meeting time - Tuesdays 5PM
- assign rough groups and projects (__tower, shaft, blades__ - Jasmine, Seba; __electrical system__ - Riley, Odalys; __fluids analysis__ - Seba, Nicola)
### Equipment manuals
__Aurora 3kW inverter__ - [data sheet](https://drive.google.com/file/d/1b_QylTKJzde8saR7A5cHfEcUz2PQZ7JJ/view?usp=sharing)</br>
__Aurora wind interface box/rectifier__ - [manual](https://drive.google.com/file/d/1YciYcLJHPdqsU5kGbLKZFx5bYpHzk-JD/view?usp=sharing)</br>
__TCMG-3kW Taechang N.E.T. Generator__ - [online specs](https://tcnet.en.ec21.com/3kW_Small_Wind_Turbine--1105310_1105312.html)</br>
__3kW Discharger Breaker__ - </br>
__3kW Dynamic Braking Resistor__ - [instruction manual](https://drive.google.com/file/d/1u_LV9H5tyxtQRk8UA6zT45W3fTitwZu3/view?usp=sharing)</br>
__Anemometer__ </br>
__Wind direction meter__ </br>
### Moving forward, we will do these things by next Thursday:
__FOCUS ITEMS__</br>
- choose design
- CAD turbine
- tower design thoughts and calculations
__also relevant__</br>
- alternating current research - how do you work with it?
- location, what tower is going to look like, how strong should it be - tower mounting
- transmission
- 3D print several pieces, wrap-around fiberglass or carbon fiber
- find a weekly meeting time
- connect wind direction meter to pole
- which type of wind turbine should we prototype?
- how can we get a system up the fastest? Sheet metal, etc...
- read through all manuals and understand the purpose of all components
- how can we charge the 24V battery system in the house?
- CAD our house and run fluids analysis
- assign projects to people
- timeline
- analysis of the tower torque
## 10/22/2020
### Anemometer mount on roof
[[File:Anemometer-house.jpeg|border|thumb]]
The anemometer is mounted at an altitude, 8.85 m (29 ft), where the wind turbine could possibly go. However, it is slightly offset from the gable. Ideally, the wind turbine would sit on the gabble as the wind speeds up when it passes over that point. Furthermore, I added a real-time clock to the system and connected the Arduino to a power supply that is independent from the inverter, which is turned off every night.
### Approximate size of vertical axis turbine
- azimuth - rotation of rotor to generator
- yaw - rotation of nacelle about vertical tower
- pitch - angle/pitch of blades about their lengthwise axis
__Towers__
- First week or two of Coursera course, wind resources, tests, and measurement part
- Personal notes in a google doc, final Report - technical report in latex, final deliverable that is more public-facing
## References
<references />