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icon Wing Width

When the radius of the turbine is chosen the width of the blade is then measured based on different aspects of the radius.

b = Blade width
R = Turbine radius
r = Radius of respective blade element
z = Number of blades
Ca = lift force coefficient by r
lambda = Rotor speed

b =

5.6 x R 
Z x Ca x (r/R) x £ 2

Thereafter the marks of every momentum point for the respective profiles is measured. The momentum points are 1/3 out on the cord measured from the profile end. A practical way to proceed is to place all momentum points on a straight line through the whole turbine. In Acad you can draw a line from Origo, with length and angle equivalent to 1/3 of the longest wing profile. Then draw lines from that end point with the length of 1/3 of the other wing profiles but with their respective angles, 180 degrees, straight opposite to their original direction.

Now you can let Acad identify the coordinates for all the end points. The first line end point is zero (0). If we choose to place the longest profiles start point in Origo, we now have the coordinates for all profiles starting points. These coordinates are fed into the program when it asks for "ucs by radius 1R", together with a "z-value". The 1R is the turbine's whole radius.

Check the wing profile page for more specifics.

Offered by Geson.