@Aceman307 The chord is an imaginary line drawn from the nose to the tail of the airfoil. There appears to me to be several ways of defining the angle of the blades. The one that I prefer is if you draw a line from the center of the turbine to the nose of the wing and set the chord perpendicular to that line, that would be a 0 degree mounting angle. Using that definition, my wings are set at 13.4 degrees nose pointed outward.
@Caleb6543 Thanks for the explanation. Lynxsteam was using around 8 degrees for his turbines. I used 7 for my last turbine but have not tried other angles.Have you tried other angles?
@Aceman307 I haven't tried other angles for this turbine. The design lends itself to holding a blade at a fixed angle, but is not so good for adjusting the angle. I'd have to make new disks for each new angle. I made a number of smaller whirlygigs to get a feel for what works. But it would appear I have more to learn.
@sirtom68 I just don't think the turbine ever got into "lift mode." Perhaps because the wings were bending a lot (one broke already by the way), or a number of other reasons. I'm planning on putting glass and epoxy on a new set of wings and trying it again. It was a first prototype; it might require a lot of adjustments. But I think it is close to working.
I'm no expert ;). But you could reduce the magnet gap quite a bit, that could x 4 your voltage from what I can see. It's hard to tell where the wind is coming from, but it looks like you might have lift there but its lost in the blades flexing so much. you could teather the with wire to the main disks. Tis also best to test on a stable load. A battery in differnt charged states will give confussing results. But nice work. I'm looking into voltage boosters quite a bit, that might help too.
Viewed some of you video...lot's of good work making things from raw material. The spinning turbine looks absolutely fine, i.e. it's spinning at a good RPM. Suggest concentrating your efforts now on the generator which is performing very very poorly. You're using saw blades which contain iron which will redirect the magnetic fields away somewhat, from your stator. So you're not getting the full effects from the magnets. Replace the saw blades.
A good view of the various parameters. Have you studied similar designs that actually perform "good" to see what characteristics they have,, or , as I suspect, you enjoy discovering these things on your own? Nice work and thanks for sharing.
@Fearlessthinker I've been sharing this on a VAWT forum and have gotten some good advice. It seems the VAWT never reached "lift mode" for a variety of reasons. Next on the agenda is to glass/epoxy some wings, mount the wings a couple degrees trailing edge inboard and try again. This is fun; when time permits. :-)
My 12 volt battery seems to slow down the turbine in the wind. Does that mean I need bigger blades? Your vawt is already spinning so fast that it appears it will not hold up for too long at that high speed It is very interesting to watch.
@wtam69 It's good for the turbine to slow down some. That lets it produce some torque and power. Mine would probably fly apart. I want to put a layer of glass and epoxy on the wings to stiffen them up.
So the too slow rpm caused the generator voltage to be too low, I guess. What kind of load did you put on the generator for the measured data? Was it a battery with too high a voltage for the output voltage achieved, or a fixed resistor?
@definitionofis I have a rectifier and a 12 volt battery so when the RPM gets high enough to overcome the battery voltage the turbine gets under load. Until that time it is basically free spinning. The current is being measured using a small resistor. I have a circuit that measures the voltage drop across the resistor and calculates the current flow.
@Caleb6543 use a boost converter to get the voltage above 12 volts. Electronically disconnect the boost when the input reaches a certain voltage level
At least it didn't self destruct.
I think the answer is that you need to increase the number of coils to load down the turbine more. Just guessing though.
Blades need to be stiffened as well.
skyl4rk 3 months ago
@skyl4rk Funny you should mention stiffening the wings, because I did that this week. The video should be coming out soon. :-)
Caleb6543 3 months ago
I am not sure what that means so there is no angle the blades are straight in relation to the center?
Aceman307 4 months ago
@Aceman307 The chord is an imaginary line drawn from the nose to the tail of the airfoil. There appears to me to be several ways of defining the angle of the blades. The one that I prefer is if you draw a line from the center of the turbine to the nose of the wing and set the chord perpendicular to that line, that would be a 0 degree mounting angle. Using that definition, my wings are set at 13.4 degrees nose pointed outward.
Caleb6543 4 months ago
@Caleb6543 Thanks for the explanation. Lynxsteam was using around 8 degrees for his turbines. I used 7 for my last turbine but have not tried other angles.Have you tried other angles?
Aceman307 4 months ago
@Aceman307 I haven't tried other angles for this turbine. The design lends itself to holding a blade at a fixed angle, but is not so good for adjusting the angle. I'd have to make new disks for each new angle. I made a number of smaller whirlygigs to get a feel for what works. But it would appear I have more to learn.
Caleb6543 4 months ago
Good work . Keep working at it. What was your angle of your blades 7 or 8 degs?
Aceman307 4 months ago
@Aceman307 I had them set so that each end of the 4.63" chord was on the same 20" dia circle.
Caleb6543 4 months ago
Rotor/Stator diameter too small maybe? I like the design. Keep it up :)
sirtom68 4 months ago
@sirtom68 I just don't think the turbine ever got into "lift mode." Perhaps because the wings were bending a lot (one broke already by the way), or a number of other reasons. I'm planning on putting glass and epoxy on a new set of wings and trying it again. It was a first prototype; it might require a lot of adjustments. But I think it is close to working.
Caleb6543 4 months ago
I'm no expert ;). But you could reduce the magnet gap quite a bit, that could x 4 your voltage from what I can see. It's hard to tell where the wind is coming from, but it looks like you might have lift there but its lost in the blades flexing so much. you could teather the with wire to the main disks. Tis also best to test on a stable load. A battery in differnt charged states will give confussing results. But nice work. I'm looking into voltage boosters quite a bit, that might help too.
20RoyalSuperKing 4 months ago
Thanks for your honest approach. I am watching and looking forward to future updates. Good Luck!
photolodge 4 months ago
@photolodge Thanks. I'm sorry it didn't perform better. This is going to take a bit of thought.
Caleb6543 4 months ago
Why charge the battery during the test? Isn't it easier to measure voltage across resistor and calculate current and power later?
th3dig1tal0n3 4 months ago
@th3dig1tal0n3 That is just how my data logger is set up. To me, that is the acid test; can it charge my battery. :-)
Caleb6543 4 months ago
Viewed some of you video...lot's of good work making things from raw material. The spinning turbine looks absolutely fine, i.e. it's spinning at a good RPM. Suggest concentrating your efforts now on the generator which is performing very very poorly. You're using saw blades which contain iron which will redirect the magnetic fields away somewhat, from your stator. So you're not getting the full effects from the magnets. Replace the saw blades.
Martin1962 4 months ago
A good view of the various parameters. Have you studied similar designs that actually perform "good" to see what characteristics they have,, or , as I suspect, you enjoy discovering these things on your own? Nice work and thanks for sharing.
Fearlessthinker 4 months ago
@Fearlessthinker I've been sharing this on a VAWT forum and have gotten some good advice. It seems the VAWT never reached "lift mode" for a variety of reasons. Next on the agenda is to glass/epoxy some wings, mount the wings a couple degrees trailing edge inboard and try again. This is fun; when time permits. :-)
Caleb6543 4 months ago
My 12 volt battery seems to slow down the turbine in the wind. Does that mean I need bigger blades? Your vawt is already spinning so fast that it appears it will not hold up for too long at that high speed It is very interesting to watch.
wtam69 4 months ago
@wtam69 It's good for the turbine to slow down some. That lets it produce some torque and power. Mine would probably fly apart. I want to put a layer of glass and epoxy on the wings to stiffen them up.
Caleb6543 4 months ago
So the too slow rpm caused the generator voltage to be too low, I guess. What kind of load did you put on the generator for the measured data? Was it a battery with too high a voltage for the output voltage achieved, or a fixed resistor?
definitionofis 4 months ago
@definitionofis I have a rectifier and a 12 volt battery so when the RPM gets high enough to overcome the battery voltage the turbine gets under load. Until that time it is basically free spinning. The current is being measured using a small resistor. I have a circuit that measures the voltage drop across the resistor and calculates the current flow.
Caleb6543 4 months ago
@Caleb6543 use a boost converter to get the voltage above 12 volts. Electronically disconnect the boost when the input reaches a certain voltage level
Martin1962 4 months ago