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Wind Turbine Write Up Jankowski 1 Wind Turbine Write up By: Matt Jankowski EDSGN 100 Sec 014 Windmill Background Wind turbines are an essential tool for capturing natural energy and are very simple to understand the mechanisms behind. It’s as simple as instead of using electricity to create wind, such as a fan or an AC unit, wind turbines use wind to create electricity. Humans have used wind to power mechanisms and toys for decades, such as setting sail on a sailboat to flying a kite on a windy day. Then we took those ideas and turned it into a way to create energy. The rotor blades on windmills act as the blades on a helicopter and are set at 20 degree angles, which will produce the most rotor rotation. When the wind blows, it catches on the blades and causes the rotor to spin. The rotor is either directly connected to or connected through a series of gears to a generator. The generator runs, produces electricity and stores it to be used. My Windmill My solidworks model consists of eight different parts, assembled together to make a free-standing horizontal windmill. First, I started by connecting the base and the lower mast with three mates: concentric, coincident and front plane-front plane coincident. I then added the upper mast and swivel shaft, using three mates to add them to the assembly. Next, three blades, the hub and the main shaft were added. To assemble the blades into the hub, I had to make three mates: concentric, coincident, and a 20 degree angle between the right plane and the flat surface of the blade. Next using a concentric, coincident and a top plane-top plane coincident, the main shaft was added onto the back of the hub. At this point, I was in the final stages of assembly. After importing ball bearings from mcmaster.com, I added the last few parts to the assembly: nacelle 1 and 2 as well as two ball bearings. Nacelle 1 was triple mated to the tower and the ball bearings were both double mated to nacelle 1 to allow them to rotate. Next I slid the main shaft through the ball bearings, mated them, and left a 0.05 inch gap between the back face of the hub and the nacelle. This gap, paired with only two mates, instead Jankowski 2 of the normal three, will allow the rotor to spin freely in the horizontal direction, as a windmill needs to. Finally, nacelle 2 was triple mated to nacelle 1, completing the windmill assembly. Vertical vs Horizontal Windmills There are two main types of windmills, horizontal and vertical. Horizontal windmills rotate on a horizontal axis (as you can see above) while vertical windmills rotate on a vertical axis (as you can see below). The vast majority of windmills you would come across are horizontal. Due to the blades being perpendicular to the wind flow they are more efficient in turning wind into mechanical energy. Both types have their advantages and disadvantages, and perform more optimally in different situations. Though horizontal axes are more efficient, vertical windmills can actually rotate with Jankowski 3 lower wind speeds than even feasible with horizontal ones. Another reason you might be more likely to run across a horizontal windmill is due to its less stressful and more stable structure. Vertical windmills on the other hand are more likely to crack and break. One type of vertical windmill is the Darrieus windmill, which can be seen in the picture below. Darrieus wind turbines can spin at extreme speeds, even faster than the wind is hitting the blades. Due to its extreme rotation speed, it might create less torque than others but this makes it optimal for electricity generation. Also due to its structured design, it is very sturdy and really only feels stress when it’s spinning at high speeds. Different situations call for different solutions and there are many types of windmills to produce the optimal amount of energy. Jankowski 4 Savonius Windmill The Savonius windmill is a vertical windmill used to turn wind into torque, which turns a shaft, therefore running the generator and creating energy. Aerodynamically, it is one of the simplest windmills to understand. As wind hits inside the scoop of the blade, it rotates it. Because of the scoop shape, when it's spinning, it creates very little drag, allowing it to spin with more ease. Unfortunately, most of the time, savonius windmills are close to the ground, because if put too high, they will easily break. This puts it at a disadvantage due to the lower wind speeds at lower altitudes. Overall it is an effective windmill, but should only be used in areas of high elevation and high wind speeds. Jankowski 5 Works Cited Admin. “Different Types of Windmills - Renewable Energy: Agriculture: Technology.” Renewable Energy | Agriculture | Technology, 16 Apr. 2016, ​ www.sustainable-hyderabad.in/different-types-of-windmills/. “How Do Wind Turbines Work?” Energy.gov, ​ ​ www.energy.gov/eere/wind/how-do-wind-turbines-work. Papiewski, John. “Horizontal Vs. Vertical Wind Turbines.” Education, 21 Nov. 2017, ​ ​ education.seattlepi.com/horizontal-vs-vertical-wind-turbines-3500.html. “Savonius Wind Turbine.” Wikipedia, Wikimedia Foundation, 18 Oct. 2019, ​ ​ en.wikipedia.org/wiki/Savonius_wind_turbine. .
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