User:Inh117/enes100/My work

Wind Turbine

Write problem/project Goal
To produce a model of a wind turbine contained by a shroud in order to demonstrate how turbines with shrouds produce more power than wind turbines with out shrouds.

My First Task
The first weekend, I conducted research on wind turbines and began looking at the concepts behind the WindTamer. this is a wind turbine design that encases the turbine blades that rotate to produce electricity. I also looked into the projections of wind energy and its place in the future as an alternative energy source. The WindTamer design is said to produce more electricity that a Horizontal axis or a vertical axis wind turbine.

Summary of actual work over first weekend
Thw WindTamer design must be fairly new as it is was not described in the books I read on wind energy. This confined my research to the internet. Also, since looking through many available motors, my original idea of using a printer motor wasn't going to work because it was brushless and would not be the best for power generation.

There has also been some debate on whether or not the shroud is best placed at the front or back of the turbine. I tried to look up the physics and mechanics of how the WindTamer design actually functions better than traditional wind turbines. I was able to find some answers in this video: Physics of WindTamer

Week1 Narrative
After some PC fans were obtained, it became clear that there were multiple designs needed to fully test the shrouded wind turbine design. The variations were a single shroud and a double shroud. The best placement for the second shroud still needs to be determined, I believe that it will function the best in the front.

Once the PC fans were in my possesion, I began to run tests on the four different wires that connected to the fan. the most obvious being the red wire and the black wire. Through spinning the fan by hand, I was able to generate about 0.32 volts of DC as indicated by the multimeter I was using.

Since the DC brushless motor that is contained in the PC fan was, in fact, producing power, the problems I initially ran into regarding brushless motors apparently not producing power were resolved. Although I would still like to explore the notion of a beter motor for power generation.

My Second Task
Since the PC fans are square, there is a large, flat end to the center iof the rotor blades. The fans must be made more aerodynamic to maximuze wind power and produce less waste. I am also looking around hardware stores for inspiration on mounting square fans securely enough to withstand the high winds generated when the turbines will be tested.

Summary of actual work over second weekend
Hardware collection was delegated to another group member and my next task is to come up with a feasible design centered around a 4 inch PC fan. After looking up a tutorial on the Loft function within SolidWorks 2010 found here: Simple Propeller Design, I was able to successfully model a PC fan as well as the back shroud of our wind turbine.

Week2 Narrative
My assigned task was to replicate a WindTamer-like design that focuses around a 4 inch PC fan. I designed the PC fan with relative ease since in my experience with CAD projects almost always involves modeling a fan of some sort. These different fans can vary dramatically so simply scaling a previously designed fan up or down does not work in all situations. I modeled the fan blades and the square case that held the fan in the center. Since this project involved shrouds, I modeled a similar PC fan case, but without the mounting struts for the motor, this compo9nent would be used as a front shroud extension.

The primary profile shape of the back shroud is a circle which conforms to the design of the PC fan case. But the case does not have additional space to mount wires to support the back shroud material. A simple plywood ring was modeled to accommodate both the 1/8 inch mounting holes on the PC fan case and 10 smaller holes to insert support wires into.

At around this point was were my experience with SolidWorks 2010 ran out. The megaphone-shaped back shroud had many design quirks about it that left me with many questions on how I was going to approach it. My original idea was to simply draw the side view of the shroud and simply revolve it around an axis. This approach was unsuitable because it did not allow for the modeling of the support wires. I then turned back to the Loft function, after sketching the profile each end of the shroud, I ran into more problems. When I tried to create the loft, instead of following the sketch I had made, it would fill in everything within the profile and then remove my profile sketch from it. I still have no idea how this could occur as I have never seen a Loft Extrude Cut function in any SolidWorks package I have used.

It is worth noting that this first shroud design was a more practical design, with the support wires modeled in the inside of the shroud. Since I absolutely could not get that design to model properly, I modeled a second design. The measurements were the same, but the support wires were on the outside of the shroud this time. I modeled a solid Loft of the two reversed profiles and then I used the Shell function to completely hollow out the inside. This design worked great on, because it modeled properly, and two, the wires on the outside make for a more interesting design.

With the components modeled, it was simply a mater of mating them together into the finished design.







My Third task
The next task will to begin actual construction of these turbines. The designed turbine shown here will take the longest time to build, so it should be flagged as a priority. the other turbines we will compare it to should be complete rather quickly.

Summary of actual work over third weekend
Implementation of the designs began this week. Being that the designs themselves are "soft" designs, they are not constrained to extremely specific measurements. This allows me to build the mounting ring with the confidence to allow for inevitable support problems that I can fix as they happen. In a perfect world, I would have had access to COSMOS 2012, a dynamic simulation software package distributed by SolidWorks. This would have allowed me to simulate different materials to different specifications. Although shroud material gathering is still ongoing, the terminal board was built for mounting the fans on and making it easier to take voltage and current readings off of it.

Week3 Narrative
Over the 3rd weekend, I began constructing the base board that the fans will be mounted on. Hex bolts were driven through the board, 2 per per fan. These will serve as electrical terminals that will make it easier to monitor the voltage and current running out of them. They are, in reality, unessential, but it will make the testing regimen easier when the time comes. Also, it is always advisable to build from the ground up as adding these terminals later would have been awkward and potentially damaging to the fans and shrouds.

This was our first time actually becoming familiar with the Engineering room and where certain things were located. It was truly an accomplishment that I was able to find eight matching nuts and bolts in the pile of miscellaneous nuts, bolts, screws, washers, etc. I was handed. Material gathering is still ongoing as there has been no consensus on what the shroud should be made of. The support structure is self explanatory, metal wire driven into a wooden mounting ring. However, there are ideas ranging from plastic wrap to cardboard to regular paper to make the shroud.

I believe that the plastic wrap will require less work to wrap the shroud. The only downside to this approach would be the necessity of further support on the back of the shroud to give it the support it needs to keep its shape. Cardboard would make this a non-issue as the stability of the cardboard compounds upon the support of the wires. The problem is that cutting the cardboard to preserve the curved (described and Lamp-Shade-like) shape of the shroud will be difficult and time consuming.

My Fourth task
This week, all of the materials have been gathered, and construction should not take long at all. Now I have familiarized myself with the engineering room, I am confident that mounting the fans and constructing the shroud will be simple.

Summary of actual work over fourth weekend
This week I rebuilt the entire system using different motors. The final assembly happened and the shrouded wind turbine was tested against a traditional turbine of the same diameter. After the assembly and testing were complete, I made the poster that summarizes our project.

Week4 Narrative
The construction of the shrouded wind turbine was completed. I built the testing board and mounted the shroud onto a small upright. since there was some extra wood, it was easy to reinforce the connection with a wood screw. A leaf blower and voltmeter were used to test the shrouded turbine against a traditional bladed turbine of the same diameter. The voltmeter was set to a 200 milliamp scale and we began recording data.

But I ran into a massive problem. The current the turbines were producing wasn't even enough to trip the sensors inside the voltmeter. The voltage refused to go above .5 volts. This was unacceptable, no usable data was being gathered. The project required a redesign using larger motors. This problem arose on the last day of building this project, and therefore I did not have time to study the new motor's operating parameters. The fan blades were separated from the motors attached to their cases. It was upon dissection that I found that there were extensive microchips inside the PC fan's motor. I guessed this to be a speed controller and encoding equipment, therefore severely limiting the amount of voltage and current that could leave the motor.

Two identical DC motors were found and placed in the rebuilt system. The traditional turbine simply needed the blades attached to the shaft of the new motor. The shrouded turbine, on the other hand, needed to be suspended in the center of a PC fan case. This required extremely accurate work to ensure the proper fit of the large diameter motor in the center mount of the PC fan case.

Once these modifications were made, testing resumed and the data I observed was amazing. The shrouded fan produced 1.2 amps and had a peak voltage of 25.6 volts. This far outperformed the traditional turbine, producing.90 amps and maxing only 21.1 volts. This project was a success in determining the validity of Shrouded wind turbines and their claims to produce more energy than traditional turbines.

I also produced the poster to be used as a visual presentation of the most relevant data to this project and I posted it to the main project page. But I also included a render here. I attempted to upload it to Google docs multiple times, but the formatting (the poster was made in power point) would continuously change at random making links to the "original" useless.

Complete Project Page
Wind Turbine