Test Plan
In order to test the wind turbine against our theoretical test values from last semester we put our models into the wind tunnel. We decided to maximize the used area in the wind tunnel with our turbine so the 9” diameter was used. In the course of our testing we made an interesting discovery that our new, larger diameter turbine would not spin in a fully sealed off tunnel. We attributed this to a few potential problems. Because our turbine was now using the most space we could afford to give it, the blades were passing by the walls of the tunnel much closer. The effect that this decrease of space had was that the wind now created eddies and turbulences that created interference with the rotation of the blades. Another theory we came up with, which was later substantiated by one of the members of the IAB, was that because our turbine was vertical it created a vortex that rose as our blades spun. In the enclosed chamber of the tunnel the vortex that was created met with the roof. The vortex was then deflected back down into the rotating turbine which then also created interference. To overcome this problem we had to keep the tunnel open around during the duration of the tests. This allowed the wind to flow freely through the turbine without problem.
Our test was set up with the turbine mounted on a large wooden block that was then secured to the table to prevent it from moving and vibrating too much during the test. The leads from the alternator were then fed directly into our rectifier which was then connected to our multi-meter which we then collected our DC voltage values from. While these voltage values were important they were not the only data we took. In order to be able to analyze our data to see what our theoretical full scale model would produce it was also important to measure the rotational speed of our turbine throughout the test. We went about this by using a cyclometer which is a device that is normally attached to a bicycle that tells you the speed of the bike wheels in mph. We attached the sensor from this device to one of the blades and adjusted the settings on the cyclometer for the radius of our turbine. During the course of the tests we recorded voltage output and rotational speed at different Hz. In order to get Hz in a form we could actually use, we then removed the turbine from the testing area and inserted an anemometer in its place. This allowed us to take a wind speed measurement at each of our Hz increments. Plotting these values we were able to create a calibration plot.
We ran our test through several times in order to make sure that our values were consistent. In order to measure our current output we then hooked our multi-meter directly into the rectifier circuit. The data collected from all of this was then plotted and analyzed.
Our test was set up with the turbine mounted on a large wooden block that was then secured to the table to prevent it from moving and vibrating too much during the test. The leads from the alternator were then fed directly into our rectifier which was then connected to our multi-meter which we then collected our DC voltage values from. While these voltage values were important they were not the only data we took. In order to be able to analyze our data to see what our theoretical full scale model would produce it was also important to measure the rotational speed of our turbine throughout the test. We went about this by using a cyclometer which is a device that is normally attached to a bicycle that tells you the speed of the bike wheels in mph. We attached the sensor from this device to one of the blades and adjusted the settings on the cyclometer for the radius of our turbine. During the course of the tests we recorded voltage output and rotational speed at different Hz. In order to get Hz in a form we could actually use, we then removed the turbine from the testing area and inserted an anemometer in its place. This allowed us to take a wind speed measurement at each of our Hz increments. Plotting these values we were able to create a calibration plot.
We ran our test through several times in order to make sure that our values were consistent. In order to measure our current output we then hooked our multi-meter directly into the rectifier circuit. The data collected from all of this was then plotted and analyzed.
Click here for a walk-through of the testing setup.