Windmill Optimization 

Project Objectives

Software Required

Materials Required

Adapted list from Civil Engineering Course instructor, Mr. Tom Dubick

Blade Design & Testing

Set Up

Before we could start the project, we needed to first understand how to use and interpret the directional current (DC)-motor, Analog Discovery 2, and WaveForm. 

To connect the devices, we put male-to-male wires in the orange wires of the Analog Discovery 2, clipped aligator wires to the other ends, and clipped the aligator wires to the corresponding positive and negative tabs on the bottom of the DC-motor. We then plugged a micro USB cord into the Analog Discovery 2 and the computer PC. Next, we opened WaveForm, clicked "scope," changed "repeated" to "screen," and set channel 1 to "500mV." We then clicked "scan" to start the program and watched the WaveForm program as we spun the motor.

Next, we soldered wires to the motor to create a more permenant, stable alternative to aligator clips. We took male to female wires, cut off and then stripped the female sides, put the red wire through the positive tab's hole and the black wire through the negative tab's hole on the motor, soldered the wires in place, and secured them in place with electrical tape.

Horizontal Axis Wind Turbine

Design

This Horizontal Axis Wind Turbine (HAWT) design was given to us as a baseline design for comparison with later designs.

3D Printing Process

We imported the STL files into PrucaSlicer, oriented them to best fit the 3D printer bed, added supports to build plate only, and set the infill to 20%. We then exported the design as an STL, opened Octoprint, uploaded the new STL, and, after cleaning the printer bed, sent the design to the printer. 

Preparing Printed Design for Testing

After removing the 3D print from the printer bed, we removed supports from the design. We then drilled a hole in the center of the hub so that it would be compatable with the motor. Next, we hot glued the blades to the hub and mounted the HAWT on the motor. 

We then connected the motor to the Analog Discovery 2 and the oscillopsope, mounted it in the windmill stand, and set a fan one foot away from the wind turbine.

Next, we opened WaveForm, ensured the device was connected, hit scope, changed repeated to screen, and started the testing process.

Testing

The highest average voltage for the HAWT was 1mV/sec at a wind direction of 0 degrees. The voltage range was 500mV/0.5sec and there were many frequency spikes as pictured to the right. The turbine worked best at 0 degrees wind direction and stopped working past ±45 degrees.  

Video of Testing

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Graph

Based on the results from the testing, the Horizontal Axis Wind Turbine is very effective but only in one wind direction. Creating an equally or slightly less effective wind turbine that can use more angles is something we will try to achieve in our next designs.

Grey VAWT

Design

This design was created with inspirations from the Savonius 'DNA' shaped wind turbines. We thought that the curved blades could catch the wind, pushing and rotating it. This first design was rather small, however, this was intentional so that we could see the benefits of smaller scale wind turbines. 

3D Printing Process

We followed similar procedures as with the horizontal axis wind turbine to print this design only we first created the design in Fusion360 and then exported that design as an STL.

Preparing Printed Design for Testing

After the design was printed, we drilled a hole in the bottom of the VAWT so that it could be mounted onto the DC-motor. 

Testing

The highest average voltage production was 20mV/sec, significantly less than the HAWT. There were smaller, but still frequent, frequency spikes and the voltage range was 40mV/sec. 

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Graph

The testing results indicate that, although this VAWT produces significantly less voltage than the HAWT, it is able to generate voltage at all wind angles. This means that if we improve the deisgn, we could become competitive, if not better than, the HAWT maximum voltage production.

Blue VAWT

Design

This VAWT design is inspired by the giromill and helix shape vertical axis wind turbines. We made it much larger than the grey VAWT in an attempt to see how size affected the VAWT efficiency.

3D Printing Process

The process as aforementioned were followed for this VAWT design. The print time was much greater for this print due to its large size.

Preparing Printed Design for Testing

We faced a plethora of problems getting this design to work. As in the other designs, we drilled a hole so we could mount the design onto the motor. Unfortunately, the motor tip length was too short for this big VAWT to be stable on. We attempted many different ways of stabalizing the wind turbine, but to no avail, the design was wobbling in the end nonetheless. The best solution we achieved was using a piece of wood to create a tighter grip on the motor tip.

Testing

The highest average voltage production was 18mV/sec, much less than the grey VAWT design. The voltage range was 40mV/sec like the previous design, however, there were more, larger frequency spikes at almost erratic intervals. 

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Graph

From this testing, we concluded that such a big design was not efficient in collecting voltage but that a slightly larger wind turbine than our first iteration may still be effective in collecting more voltage. The design was, however, still equal in voltage production in all wind angles.

Yellow VAWT

Design

This design was inspired by the cup anemometer and similar designs we saw our fellow classmates trying out. We scalled this design at a middle point between the grey and blue VAWTs to attempt a maximized efficiency. Furthermore, this design included the 'cupping' and 'pushing' concepts present in the grey VAWT that was more successful than blue VAWT. 

3D Printing Process

The same aforementioned process was followed for this VAWT design. 

Preparing Printed Design for Testing

This turbine was fairly easy to mount after drilling a hole in its bottom, however, removing the supports from the cup-shapped blades was rather challenging. With the use of plyers, we were able to successfully remove them.

Testing

The highest average voltage production for this design was 40mV/sec, our highest VAWT voltage yet. Similarly to the other VAWTs, this turbine also worked (with consistent voltage outputs) at all wind direction angles. The voltage range was 40mV/sec and the frequency spikes were rather small but definitely present.

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Graph

From our testing, we concluded that this yellow VAWT was our most successful design. We found a good size for the turbine as well as an effective turbine blade shape. As our best design, we will move foward to achieve more consistent DC-motor voltage through signal filtering.

Electronic Componenets

As I have no background thus far in electrical engineering, most of the electric-componet-decisions were made by my partner, Maggie. However, I helped with the soldering and testing of the circuit designs.

I plan to get more expierence and knowledge about electrical engineering by either taking the class my senior year or through Fab Academy. These concepts were a bit challenging for me to understand, however, in the below video is my best understanding of how the board is used in the design/wiring. 

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Provided image for how the PCB board optimization can be accomplished

Filtered vs Unfiltered Signals

As evident in the pictures, the filtering reduces the static and refines the voltage to a stronger, more consistent voltage.

With Filtering

Without Filtering