Author Topic: My New Blades (Read 4558 times)

nekit · « **on:** March 09, 2010, 05:47:01 PM »

Just got my new blades from Royal Wind and thought some people might be interested.

http://www.royalwindandsolar.com/index.php?option=com_content&view=article&id=48&Itemid=

57

Nice quality blades made from laminated Ash. 8.5' long for 17' Axial Flux Generator. Weigh approx. 19lbs each.

Use the GOE 222 profile used by Wincharger for many years. Fairly similar profile to the current Bergey SH3052 profile. Cost $145 each

I'm very happy with them. Thanks Dave M. at Royal Wind

Rob L

don1 · « **Reply #1 on:** March 09, 2010, 08:35:37 PM »

Pretty dern good lookin blades there nekit. Shame to put them way up where no one can see them.

What do you plan on sealing them with?

tecker · « **Reply #2 on:** March 10, 2010, 02:43:31 AM »

I like that Foil I would be very interested in the performance. I hope you post back on that .

HaroldCR · « **Reply #3 on:** March 10, 2010, 05:39:37 AM »

In the photo, that leading edge looks flat or square to the shape.

Is that actually what the blade is shaped like on the leading edge

SparWeb · « **Reply #4 on:** March 10, 2010, 07:22:03 AM »

The leading edge isn't so bad - it's the trailing edge that needs some work. Try shaving/sanding it down until it's almost sharp. The blades will be quieter at the least and perform better at the best.

They do look good though, gotta hand it to them.

Dave B · « **Reply #5 on:** March 10, 2010, 09:13:18 AM »

In the end profile photo the leading edge appears flat in the photo as well as the trailing edge just a bit. This is not so, it is because the corners of the tips of the leading edge and trailing edge are slightly rounded just to take the sharp corner off. It is hard to visualize the "depth" in the photo. The leading edge is rounded the entire length of the blade carving just as you would expect. A slight bit of stock is left on the trailing edge to help protect it during handliing, the customer can elect to sand this to a knife edge if they like. The low res. photo requirements for the site never do complete justice to the actual product, these blades are very high quality.

Dave B.

Royalwdg · « **Reply #6 on:** March 10, 2010, 09:18:26 AM »

The trailing edge should not be sanded to a sharp edge if you want long term durability. These blades have a tailing edge of about 1/16 inch. The picture is taken close up and the sanded radius on the tip make things look a little strange because of the angle that you are seeing it. The leading edge is not flat. It is a normal 222 profile with a very blunt point slightly downward. thanks Rob for the positive feed back. Dave Moller

veewee77 · « **Reply #7 on:** March 10, 2010, 09:52:53 AM »

Completely off-topic, but. . .

What year is your bus?

Blades look great! Get those dudes up in the air where they belong! They want to FLY!

DougS

taylorp035 · « **Reply #8 on:** March 10, 2010, 10:00:10 AM »

Keeping everything else constant, how much benefit is there to having this 222 design instead of making a flat face with the standard airfoil? Trying to replicate the 222 design would be very hard to do by hand, but with enough free time....

SparWeb · « **Reply #9 on:** March 10, 2010, 10:41:21 AM »

Thanks!

nekit · « **Reply #10 on:** March 10, 2010, 12:24:01 PM »

That's just the way it looks in the photo. The corner is rounded off and at that angle it makes it look square. It has a nice rounded corner. Google GOE 222 and it matches that profile exactly.

Thanks,

Rob L

nekit · « **Reply #11 on:** March 10, 2010, 12:27:49 PM »

75 VW Westfalia w/ 65,000 original miles.

Thanks

Rob L

fabricator · « **Reply #12 on:** March 10, 2010, 01:17:44 PM »

So, where is the 10' measured from? is it the air foil length or the total length of the blade with air foil and straight?

Dave B · « **Reply #13 on:** March 10, 2010, 03:34:10 PM »

Fabricator,

It's the total length of the blade. Carved length plus root length and there is some flexibility here with regards to these dimensions depending on your hub mounting arrangement.

Dave B.

fabricator · « **Reply #14 on:** March 10, 2010, 04:03:55 PM »

Thanks Dave.

HaroldCR · « **Reply #15 on:** March 10, 2010, 04:15:58 PM »

I should have added: Them are NICE looking blades. Are they tapered width wise from end to end

Kinda looks that way in the photos.

Yeah, I know, Photos are deceiving.

Dave B · « **Reply #16 on:** March 10, 2010, 11:05:59 PM »

Harold,

We appreciate the compliments on these blades. There is no taper and no twist to these blades. The carved area is an exact duplicate of the Got 222 profile. This unique profile generates a tremendous amount of torque as well as running very quiet even at high speeds.

Dave M & Dave B

HaroldCR · « **Reply #17 on:** March 11, 2010, 05:44:29 AM »

When we were selling Winchargers and bargeys, they had the same or nearly same profile. The bergeys were - are impressive machines.

I made mine to Jacob's specs, and they performed well. Now, I am about to receive a treadmill motor, and want to use a GOOD profile. We live on top of a high hill, and wind is 75% or the time, and usually around 18 MPH or more. I don't have the facilities to turn metal, so, I'm extremely limited to what I can do to prevent overspeed destruction.

I WANT to build a governed system, with furling. Been reading everything I can find. This site is awesome. A few things I don't agree with, but, that's me.

Wind is 1st priority. Water is next. Should have 3 UPS's here in the next few days. Just need to get the motor so I can carve blades.

Thanks for the info on your blades, Dave. Nice work. Do you not recommend metal protective covering on the leading edges It's amazing how much dinging happens on top of 100 foot towers.

Dave B · « **Reply #18 on:** March 11, 2010, 08:00:43 AM »

Harold,

It's a good idea to protect the outer leading edge of the blades if you suspect an abraisive environment. We have used stainless steel tape but there are many other options as well. I think I would do this for any smaller higher RPM machine. Dave B.

defed · « **Reply #19 on:** March 11, 2010, 04:01:58 PM »

has there been any comparisons done on this 222 profile vs the style blade used in Hugh's and Dan's books? does one work better at certain sizes and/or avg wind speeds?

i'm not far from the Royal Wind, just need to decide if i want to save some $ and carve my own (10') or save some time and buy some.

still have to get my 4' test model done 1st tho.

ChrisOlson · « **Reply #20 on:** March 13, 2010, 07:11:35 AM »

I've never tested the 222 but I've spend a lot of time comparing the flat-face profiles to the S809 (very similar to the GO222 in performance characteristics). I've concluded the S809 is better and there's a reason that profile is used on the majority of utility-scale turbines instead of flat-face blades.

I've found that the symmetrical airfoil puts out more power in low and midrange wind speeds, it requires a generator with a couple extra turns of wire to take advantage of the low-end torque, and at higher wind speeds there's not much difference. On both my 10 footers I get 30-35 more watts out of them (by rewinding the generators with two more turns of wire) in the 10-12 mph speed range than I got with flat-face, while not giving up anything to the flat-face blades at high wind speeds.

The main advantage of the flat-face profile is that it's easy for the homebuilder to make. Attempting to build S809's or GO222 blades using widely used homebrew blade construction methods would be very close to impossible. The airfoils are too complicated to get consistent results using the construction methods and tooling most homebuilders use.

--

Chris

defed · « **Reply #21 on:** March 14, 2010, 02:34:58 PM »

just to make sure i understand your terminology....flat faced is the type of blades used in the Dan's and Hugh's books...because the face, even though it 'twists', is still in a flat plane? whereas the blades referenced here have a curved profile?

ChrisOlson · « **Reply #22 on:** March 14, 2010, 06:53:11 PM »

Yes. "Flat face" means a non-symmetrical airfoil, i.e. one side the airfoil is basically flat, the other side curved. Symmetrical airfoils like the S809 and GO222 have both sides curved.

Symmetrical airfoils don't typically create lift at zero angle of attack, and they are very low drag - that's why they're used on supersonic aircraft. Flat face airfoils create lift at zero angle of attack and they exhibit higher drag coefficients.

The setup on a wind turbine is totally different once you go to a symmetrical airfoil. Every single one of my turbines (I have three of them flying) that I switched from flat face profiles to S809 furled properly before I switched the blades. After switching the blades to S809 airfoils they failed to furl - they stay pointed right into the wind and just keep putting out more power. This is because the S809 airfoil transfers more of the wind's energy to rotational torque instead of thrust (drag). Like I said, there's a reason that airfoil is the primary one used on the Big Boys.

The main advantage of the flat face profile, for the homebuilder, is that it's easy to shape with some level of consistency. And it works "good enough" for most homebrew turbines. But if you want to build a turbine that puts out an honest 1 kW with 8 foot blades @ 24 wind speed, in my opinion you should be looking at the more modern airfoils like the S809. The flat faced airfoils were developed back in the 20's and 30's. The more modern low-drag airfoils (mostly developed by NASA) came into being when aircraft started flying faster than the speed of sound and needed low-drag coefficients to do it.

I ended up winding bigger generators for every one of my machines after going to the new blades to load the blade disc more and get them to furl. And I've spent a LOT of time trying different blades and airfoils to see how they work.

--

Chris

ChrisOlson · « **Reply #23 on:** March 14, 2010, 07:05:46 PM »

Symmetrical airfoils don't typically create lift at zero angle of attack, and they are very low drag - that's why they're used on supersonic aircraft. Flat face airfoils create lift at zero angle of attack and they exhibit higher drag coefficients.

I quoted the above because I'd like to point out another factor - startup. Flat face blades generally start quicker (at lower wind speeds) than symmetrical blades. This is because they exhibit higher drag so just a breath of wind will start them turning.

Many homebuilders consider this a "good thing" but I don't. There's very little power in low wind speeds below 8-9 mph and I'd rather have my turbine parked waiting for decent wind to make real power than doing what I call "recreational" spinning", wearing your bearings out with the turbine running just below cut-in on low wind speed days.

--

Chris

defed · « **Reply #24 on:** March 15, 2010, 02:28:24 PM »

ok, thanks for that info. i am going to carve some flat faced blades for my 4' test model. depending on how well the carving goes (and how well the 4' flies), i will either carve blades for the 10' that i plan to make next, or buy a set from the place referenced in the original post. i live fairly close to them, so could go pick them up and not have to have them shipped.

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Author Topic: My New Blades (Read 4558 times)