gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
220217-1710 EST
Quite a few years ago when my brother in law was chief materials scientist at GE Aerospace they had the problem to design and build one of the first new large wind generators. I believe at that time the blade was to be about 80 ft long. This was a very formable task. Fundamentally it was a large fiberglass structure. I don't know whether anyone else had built such a high powered windmill previously.
He also oversaw the development of the first satellite antenna for direct TV transmission to earth. This was for Japan. This required development of a composite material with near zero temperature coefficient from a very low temperature to over 100 C.
The velocity of sound is about 1000 ft/second. Thus, the tip of the blade velocity must be below that speed. This means maximum RPM at a 160 foot diameter is 160 * 3.1416 = circumference = about 500 ft, and maximum RPS = 2. But one would not run at quite this high a speed. These windmills produced a lot of ground vibration that could be felt some distance away.
A few years back at a local SME meeting I went on a tour of a blade manufacturer near Lansing, Michigan. Here they had a long horizontal machine that could produce a blade up to about 110 ft long. Why Lansing? Because it is about half way between our two coasts where there are large wind farms.
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Quite a few years ago when my brother in law was chief materials scientist at GE Aerospace they had the problem to design and build one of the first new large wind generators. I believe at that time the blade was to be about 80 ft long. This was a very formable task. Fundamentally it was a large fiberglass structure. I don't know whether anyone else had built such a high powered windmill previously.
He also oversaw the development of the first satellite antenna for direct TV transmission to earth. This was for Japan. This required development of a composite material with near zero temperature coefficient from a very low temperature to over 100 C.
The velocity of sound is about 1000 ft/second. Thus, the tip of the blade velocity must be below that speed. This means maximum RPM at a 160 foot diameter is 160 * 3.1416 = circumference = about 500 ft, and maximum RPS = 2. But one would not run at quite this high a speed. These windmills produced a lot of ground vibration that could be felt some distance away.
A few years back at a local SME meeting I went on a tour of a blade manufacturer near Lansing, Michigan. Here they had a long horizontal machine that could produce a blade up to about 110 ft long. Why Lansing? Because it is about half way between our two coasts where there are large wind farms.
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