remix of lulu109's wind turbine

thingiverse

UPDATE: This model has been upgraded. Please see my latest design. I recreated lulu109's wind turbine blade using an actual wind turbine blade profile (SA833) and correct twist, replacing the original propeller-like twist with the opposite airfoil camber required for efficient energy production. The 1:100 scale remains unchanged, but a 50% scale adjustment will be necessary for the 1:200 version to ensure accuracy. Unfortunately, this upgrade won't significantly improve power generation due to differences in Reynolds numbers between scaled and real-world models. For those interested in designing functional blades, QMIL and QPROP are excellent programs utilizing blade element theory. However, they come with a steep learning curve and require an aerospace engineering background for effective use. Below are the modifications applicable to the 1:200 scale: A ring can be attached to the base of the model to accommodate AA batteries, which still requires grinding out one rib inside the base for proper fitment. Additionally, the base screw holes won't align with the ring, and a switch can be glued into a small slot in the upper surface of the top base part. The motor I used is a "DC 6v 30-500RPM long shaft Mini Micro Metal Gear Motor Reduction DIY Model M3", which has been modified to reduce RPM. The original motor was cut down to 42mm, and a 55mm M3 shaft was reduced to fit the model. A 3mm self flashing/blinking white LED is used for lighting, which blinks at approximately 2Hz but can be powered directly by the AA batteries without additional electronics. However, the hole for the LED had to be drilled out to 3mm to accommodate its leads. When scaling down the nacelle, the motor holder/clamp parts are no longer wide enough for the modified motor, so those sections must be broken off. If using a 3mm shaft, the nacelle's shaft holes need to be drilled out to 3+mm to allow proper fitment. The motor and long shaft can then be inserted through the back of the nacelle after cutting away part of it. Two 6mm OD, 3mm ID, 2mm wide ball bearings were used for added stability, although they might not be necessary due to the model's low weight. After wiring up the components, the motor should be hot glued/wedged in place before gluing on the grill and cutting piece of nacelle. The original hub/cone was drilled out to 3mm and secured with super glue. Alternatively, tiny grub screws could be used to hold it in place instead of adhesive.