Buy my book 'Windpower Workshop' and read the whole story : Content Defining drag vs lift forces page 2 Finite element blade design page 3 The maths of lift and drag page 4 Setting the
Trang 1Notes based on a session during the Centre for Alternative Technology Windpower Course
Notes written and taught by Hugh Piggott with input from Claus Nybroe.
Hugh Piggott writes:
The first time I did this talk at CAT they threw me in with no preparation, "Just come as you are!" and I had to wave my arms about a lot. Since then I have done it countless times, but I still get more than a few blank looks. It's probably the most obscure bit of the course. Finally after about ten years, I have produced a full set of notes. I am so pleased, I asked Ian to put it on his site, and he has! Thanks Ian. Sorry I did not explain Betz's theorem, or 'tip speed ratio'. Buy my book
'Windpower Workshop' and read the whole story :)
Content
Defining drag vs lift forces page 2
Finite element blade design page 3
The maths of lift and drag page 4
Setting the best blade angle page 5
Shape of the apparent wind page 6
Optimising the chord width page 7
'Back of an envelope' design page 8
Factors affecting power coefficient page 9
Ideal shapes and practical limits page 10
Pros and cons of high speed rotors page 11
Variation of size and twist windmill blade page 12
Trang 2Defining drag vs lift forces
Trang 3Finite element blade design
Trang 4The maths of lift and drag
Trang 5Setting the best blade angle
Trang 6Shape of the apparent wind
Trang 7Optimising the chord width
Trang 8'Back of an envelope' design
Trang 9Factors affecting power coefficient
Trang 10Ideal shapes and practical limits
Trang 11Pros and cons of high speed rotors
Trang 12Variation of size and twist in a 2.3mdiameter wooden windmill blade