Blog #4: New Prototype

Early last week, unsatisfied with the performance of our prototype turbine, with creativity inspired by the materials at hand, we dove back into the blade design. In this attempt, we aimed for a more helical design as shown below. 

This type of blade design is very effective for small-scale turbines with lower wind speeds. They are effective in these areas because of the very minimal weight and surface area which reduces drag. I had been thinking about this type of design for a few days, but, at the time, we did not have any materials available that could be bent/molded into a curved shape. However, as soon as I saw a fairly large sheet of thin, flexible plastic, my mind started racing, trying to think of ways that we could mold it. After some short trial and error with bending it around a large cardboard tube into a spiral shape, we realized we were on the right track. We put on some gloves, grabbed the heat gun, and proceeded to heat the plastic just enough so that it was pliable, but not to the point of melting. At that point, it just became a process of heat, mold, heat another section, mold, and so forth. Once we completed two blades in this manner, we drilled holes near the bottom of each so that we could fasten them to the bracket near the bottom of the shaft on our original prototype. You can see, in the following picture, me trying to slightly adjust the blades so that they would attach to the shaft better. 

Our next step was essentially just attaching the blades at the top of the shaft with some hot glue, then hooking it up to a voltmeter and seeing how much energy we could produce with the fan. The following is our first trial.



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