{"id":164,"date":"2012-10-03T16:01:25","date_gmt":"2012-10-03T20:01:25","guid":{"rendered":"http:\/\/blogs.bu.edu\/ek130wind\/?p=164"},"modified":"2012-10-10T15:15:14","modified_gmt":"2012-10-10T19:15:14","slug":"wind-turbine-blade-design-and-testing-project","status":"publish","type":"post","link":"https:\/\/blogs.bu.edu\/ek130wind\/2012\/10\/03\/wind-turbine-blade-design-and-testing-project\/","title":{"rendered":"Wind Turbine Blade Design and Testing Project"},"content":{"rendered":"<p><strong>Wind turbine blade design and testing project<\/strong><\/p>\n<p>Brian Greco<\/p>\n<p>Nathaniel Michener<\/p>\n<p>Mike McNally<\/p>\n<p>Patrick Husted<\/p>\n<p>Daniel Kim<\/p>\n<p>&nbsp;<\/p>\n<p>Blade Geometries:<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Blade-geometry.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-319\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Blade-geometry.jpg\" alt=\"\" width=\"273\" height=\"69\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>The experiment used 3 rectangular blades with a constant width of 1.5 inches. From hub to tip, blades had span lengths of 5 inches, 7 inches, and 9 inches; the actual blade surface area was less because .75 inches were dedicated to the dowel attaching the blade to the hub. Change in pitch was also explored. With each span length, different pitches were tested for power output. The pitches tested: 5 degrees, 15 degrees and 30 degrees.\u00a0 Thus, a total of 9 unique blade arrangements were tested at 5 different wind speeds.\u00a0 Following are power curves comparing first the impacts of blade length at a given pitch, and next the impacts of blade pitch with a given length.<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Calibration.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-320\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Calibration.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Calibration.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/Calibration-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5deg.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-313\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5deg.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5deg.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5deg-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>In the case of 5 degree pitch, 5 inch blades seemed to function best, with significantly better performance than the 9 inch blades.<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/15deg.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-317\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/15deg.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/15deg.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/15deg-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>A 15 degree pitch angle changed things; all three blade lengths were now closer in their performance and better than at a 5 degree pitch.<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/30deg.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-318\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/30deg.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/30deg.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/30deg-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>The 30 degree pitch caused a significant drop in performance across all three blade lengths; blade length seemed to have almost no effect whatsoever at this pitch angle.\u00a0 Cut-in speed was better, however\u2014the blades started moving in about 7 mph winds, which was only possible for the longer blades at lower pitches.<\/p>\n<p>&nbsp;<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5in.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-314\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5in.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5in.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/5in-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>The 5 inch blades are interesting; the curves show a less-than-distinct trend.\u00a0 At different wind speeds, different pitch configurations seemed more efficient.<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/7in.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-315\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/7in.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/7in.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/7in-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>The 7 inch blade curves are far clearer; the 15 degree pitch is the most effective, as expected.<\/p>\n<p><a href=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/9in.jpg\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-316\" src=\"http:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/9in.jpg\" alt=\"\" width=\"481\" height=\"289\" srcset=\"https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/9in.jpg 481w, https:\/\/blogs.bu.edu\/ek130wind\/files\/2012\/10\/9in-300x180.jpg 300w\" sizes=\"(max-width: 481px) 100vw, 481px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>The 9 inch blades show the same trend, with the 15 degree pitch power curve being best, but the blades pitched at 30 degrees are a close second.<\/p>\n<p>&nbsp;<\/p>\n<p>Bulleted Lessons Learned:<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 Higher wind speeds at 9 inch span length caused potentially dangerous vibrations<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 The most optimal blade length and pitch was 7 in and 15 degrees<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 Longer blade lengths do not necessarily improve voltage or current generated; in fact, the 9 inch blades had the lowest power outputs<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 High pitches do not increase power output, but make cut-in speed lower; therefore, a turbine in a low-wind environment could function better with a pitch higher than 15 degrees, even though that is supposed to be the optimal angle<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 Variation in blade length at higher pitches shows no change in power output at this scale, and showed less-than-distinct trends at lower pitches as well; it was obvious that the 9-inch blades were worst<\/p>\n<p>\u25cf\u00a0\u00a0\u00a0\u00a0 Longer, heavier blades still manage to have lower cut-in speeds, especially combined with high pitch angles<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Wind turbine blade design and testing project Brian Greco Nathaniel Michener Mike McNally Patrick Husted Daniel Kim &nbsp; Blade Geometries: &nbsp; The experiment used 3 rectangular blades with a constant width of 1.5 inches. From hub to tip, blades had span lengths of 5 inches, 7 inches, and 9 inches; the actual blade surface area [&hellip;]<\/p>\n","protected":false},"author":3516,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[26709],"tags":[],"_links":{"self":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/164"}],"collection":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/users\/3516"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/comments?post=164"}],"version-history":[{"count":10,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/164\/revisions"}],"predecessor-version":[{"id":269,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/posts\/164\/revisions\/269"}],"wp:attachment":[{"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/media?parent=164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/categories?post=164"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.bu.edu\/ek130wind\/wp-json\/wp\/v2\/tags?post=164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}