I am currently finishing a two year engineering course on wind turbine tech. we had a module on 3d desingn (solidworks) and for one of the assignments we designed a scaled down turbine blade , printed it and tested it in the college wind tunnel recording rpm. Amazingly i made an rpm reading of 80rpm on my turbine with which i was well pleased....
This instructable will guide you on the designing of the blade using solidworks and i assume you have some basic experience if not on solidworks then some other 3d package. If not dont frete i have uploaded the screen shots i used in a.doc file along with the actual solidworks Part drawing. Good Luck!
Step 1: Drawing the Turbine Blade
Step 2: Inserting the Picture
Step 3: Stations
Now using lines, arcs or splines trace over the outside of the picture using the points as joints, then delete the picture you inserted to reveal the outline sketch of your blade, do this in the side panel.
Step 4: Adding New Drawing Planes
Step 5: Adding the Curves
The other sketches along planes 2 - 7 will have one side flat and the other curved similar to an aeroplane wing reflecting the required shape for the aero dynamics, if you were standing infront of a turbine watching it turn it is this front face of the turbine you would be looking at.. The straighter of the two long lines we traced from the photo is called the leading edge, when the turnine is rotating it is this edge which will be breaking the air as it rotates , It is for this reason i will make it more round than the trailing endge on the other side. I used spline lines with around 4 points to each, making them easier to manipulate to the desired shape and curve.
Step 6: Rear Side of Blade
Step 7: Adding the Surface
Step 8: Make It Solid
Now we want to join the two long surfaces and the two 'Planer Surfaces' we just created together, we accomplish this by using 'Surface Knit' and selecting Try to Form a Solid
If you have been successful when the blade is cut into two sections it shou;d be clear to see the inside is no longer hollow but a solid, this will be necessary for 3d printing later.
Just finish the blade tip off by using 'Features' - 'Dome' and select the face end of the tip, adjust the length to your own preference 0.1 inches was fine for me.
draw a circle big enough to fit the three blades. Next use 'Features & 'Extrude Boss/Base' in both directions. The 'Fillet' or 'Dome' the front side (the same side as the flat side of the blade).
Using 'Circular Pattern' select the 'Bodies to Pattern' i.e. the blade to make our 3 blade turbine we are all familiar with.
Step 10: Finale
Feel free to add all sorts of materials to the blades for some really cool renderings.
i have uploadedd the screen shots and the Blade 'Part1' and the hub as i have drawn it in this instructable,