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Messages - rcavictim

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1456
Waste Motor Oil / Re: Waste Motor Oil Refining
« on: August 08, 2006, 05:49:46 AM »
Fuller's Earth is a very fine dietematious (woo-ee, I bet that's wrong!) earth and is named after "Fullers" that made and dyed cloth.

About 99% of a sack of 'oil dry' is Fuller's earth.  Kitty litter has wood chips and perfume and anti dust stuff in it too.

Red wine filtered through Fuller's earth comes out pale pink.

I buy the unscented, dry clay cheap brand litter.  No parfum and I don't see any wood chips.

What does red wine taste like after filtering through kitty litter? :D  Some experiments are best left untried.

1457
Other Slow Speed Diesels / Re: Detroit 2-71
« on: August 07, 2006, 07:44:10 AM »
Ill  you can scrap the 300 pounds of copper wiring in the Delco generator head for $4/pound. .

-Jack
Quote

I called the scrap dealer last Friday for a quote on copper.  He's only paying $2.00'lb.  He said that $3.50/lb price was for traders of new Cu on wall street.  I thinks I'm talking to the wrong dealer.

Jack, I'm looking for a delco generating alternator off a 2-71.  Want to sell me yours?  Actually I'm looking for any 6 pole (1200 RPM) ST type 2 bearing head rated at 20-30 kW for my wind turbine project.

1458
General Discussion / Re: AFTERMARKET PARTS AND ENGINES
« on: August 05, 2006, 02:58:58 PM »
Where's Monty Python when you need them?

Spam, spam, spam, spam, spam, spam, spam, spam....bloody Vikings! ;D  Do you have anything with a little less spam in it?

1459
Waste Vegetable Oil / Re: Scalable Centrifuge to clean up VO
« on: August 04, 2006, 06:11:41 PM »
Here is a simple centrifuge Barrett made for his steam car, to separate any oil from the condensed steam before pumping the water back to the boiler.

That is very similar to what I my own head scratching had come up with!  I was going to investigate the possibility as I mentioned above of employing a torque converter housing on a vertical axis.

1460
Waste Vegetable Oil / Re: Scalable Centrifuge to clean up VO
« on: August 04, 2006, 01:31:38 PM »
I have been giving serious thought to designing my own centrifugal fuel oil filter as an easier alternative to a vacuum distillation plant.  One thing I see as a design shortcoming is spinning the 'fuge inside a larger stationary containment vessel with oil in between the two surfaces.  The drag forces introduced here are totally a power waster  I'm thinking of spinning the separator in air and providing the oil I/O ports through the the central shaft.

I have also been wondering if there is any way to employ an automotive automagic transmission torque converter as the 'fuge.  These will safely handle plenty of RPM.  I'm sure one would have to open one and modify it.  Cleaning may be a problem.

1461
What blade profile have you decided upon?

What is the cl/cd?

Solidity?

Have you drawn out the blade profile at the various stations reynolds numbers?

What method will you emply for protecting the machine against high winds?..forget a mechanical brake, they are not reliable enough. They are for emergency shutdown only and used for brief periods. Forget electrical braking, it will fail eventually.

My suggestion for maximum energy caputure and production is a large swept area, greater than what the math spells out for your choosen gen size. The adjustments can be made later on to take this mod into account. Build a dual rotor gen and be happy with the cutin far lower than ANY other gen, and the higher efficiency. It is also best to run with a higher voltage than you'd expect. 48v is the optimum figure when other sources of RE come in such as PV and Hydro. I build 3 phase dual rotor and switch between start and delta wiring depending on the gen RPM. The switching must be done sensibly and not immediately, to counter killing relays and casuing undue stress in the gen. The nature of wind is not predictable and we cannot say for certain what its speed will be in x seconds from now. So a more relaxed approach to switching wiring schemes works best.   

Run the 3 phases down the tower and into your rectifier block in the battery shed, then into charge controller and dump load. Now your cooking!

Matching blades to a given and known gen, is a science and not something to just jump in and try. Paying a little attention now to your design and the carving of a set of blades will pay you back many times more than a wind turbine that is just hacked togther. It will also make the difference on low wind days of having power, and not having any. Nobody likes to sit in the dark.

I have built many home made machines and they run along side my Lister CS. Everything is home made and to a high standard, I cant stand cheap engineering. Sliprings are made here too, no shortcuts and no commercial junk.

With a little care you will out perform any of the small scale machines, none of them have the build quality or longevity of a properly engineered machine. I guess most buyers will not spend the money. Its a bit like a Lsiteroid and a Lister, the same but different!

Above all, have fun with it. There is no greater thing to get you grinning than really free power.

Emerald


Emerald,

Thank you for the input and questions.  I haven't given a lot of thought to the blade yet.  I won't need blades for a while yet.  What I have envisioned for the first set of blades will be formed from steel and will use a section of the 4-1/2" O.D. X0.125" wall steel irrigation tubing I have in stock as the root.  The airfoil will be sheet metal welded on. I will likely fill them with expanding foam to stabilize them and keep out water that could turn to ice and cause unbalance.  I expect to bury an aircraft cable within the spar of each blade to keep it from launching from the hub if the root or spar fractures catastrophically anywhere along it's length, although the most likely place is at the connection area to the hub. If you have seen the historically important Smith Putman machine you see what I am roughly thinking of for two blades.  As I said earlier above, diameter 36-40 feet.  My solidity will be in the 10-15% range I think.  Probably won't have a twist but will be tapered.  I'm proposing 4 feet wide at the hub and 2 feet at the tip.

I agree that a mechanical brake is not to be relied on for speed regulation.  I have it in the system as a way to stow the blade and to haul it to a stop quickly in case of an emergency.  It will have an automatic mechanical activation which will be triggered by excessive vibration or unusual/uncontrolled yawing.  It will also be under electrical control.  My speed will be controlled by adjusting the blade pitch with an electric servo system.  The blade can be feathered to not spin even if pointed straight at the wind.  In addition, the azimuth is motor driven and the blade can be actively set to track a desired offset angle to the true wind direction if desired.  I have no plan to try to slow the turbine by overloading the generator head.

Because I can actively adjust the blade pitch I am planning that my blade will be bigger as you suggest so that I can take better advantage of low-medium wind days.  No sense having a machine that makes it's rated power only just before a storm.  I expect to see a steady 3-5 kW happening most of the time with this machine and full power of 20 kW plus on the cold windy days in the winter when I need the power for resistance heaters.

I want to see several hundred volts AC, most likely 3-phase coming down thhe tower and 750 feet across the field to the shop where the controller and any active ratio transformer system, rectifiers and batteries will be located, in a heated building out of the weather.
No plans for a battery bank that can process the full capability of the turbine, nor inverters of that capacity. Batteries make 'free wind based electricity' more expensive than grid electricity.  I may have a forklift battery and several 1 kW inverters for loads in the house that require precision AC. This battery can also be topped up by my diesel plants.  No need for a dump load.  The excess wind power when available either won't be generated if not needed (throttle back the turbine) or used to run a dedicated high wattage incandescent lighting buss in the shop in the summer for  light, and also resistance heaters for space heating in the house and shop in winter.  Look at that fool he leaves all the light on all the time!   ;D

I'm not actually planning to go off-grid entirely just now.  That's a big step.   My main need for the big turbine is as an electric furnace to offest my crippling winter propane  heating fuel expenses.  Resistance heaters don't care about voltage and frequency.

1462
Recently I tried to ask a question in the new DIY Forums about improving the performance of an induction generator and it went way off topic quickly as a discussion of my particular proposed use of such a improved induction machine, in a wind turbine.  It seems to me that this might be a good time to introduce a new subject area in the new DIY section specifically for the discussion of DIY wind turbine power generators.

Please vote in this five day poll and if the consensus is positive perhaps the management will give us another subject area.

1463
Scrap dealers are culpable for much this trade.
Paul

I agree.  I think this has gotten to the point of being a real public safety issue besides an inexcusable crime against the rightful owners of stolen property.  I have actually seen the police show up on occasion at my local landfill site to look for stolen bicycles, etc.  I think the police need to show up a scrap metal places and warn the dealers that accepting items like manhole covers could get them in trouble.

1464
OK, back on topic.  Earlier I said;

"Unfortunately i won't have 1800 RPM, except maybe just before launch. :o    From the reduced speed operation I've experienced often with my VW plant run at 1200 RPM  instead of 1800, I could probably count on 2/3rd's power spinning a 30 kW 4-pole ST head at 1200 RPM, so I'd see 20 kW at 45 Hz and reduced voltage.  Trouble is that 2/3rds speed is not normal and will only occur on really windy days."

I just remembered that one of the long established US wind turbine manufacturers, Bergey or Jacobs, currently offers a 15 or 20 kW machine where the output is 45 Hz at maximum power.  This makes it pretty obvious that they are using an off-the-shelf, synchronous AC gen head at 2/3rds nameplate RPM as a maximum.  They would have the exact same problems, if indeed any exist at all, of running an ST type head at very reduced fractional RPM most of the time.  Perhaps I need to look more closely at obtaining a 30 kW, 4-pole ST head as a useable plan-B if I cannot acquire a more desireable 6-pole alternator.  The one big issue with a oversized head run derated is the unnecessary extra weight burden it places on the tower and the cost increase for more tower integrity.

1465
The machine has autocalibration using ambient air but to be valid for EPA it must have a fresh calibration using an approved calibration gas at an approved test facility.

Mike

Yeah, you gotta get a lecture bottle of Mil Spec Air.  ;D

1466
Want to see some big DC traction motors?

http://www.putfile.com/dougwp

Look at the movies. Two 300 kw ABB locomotive traction motors front and back same type as used on light rail.

There is another option, generate the DC invert and to ac and transfor up too the 600 you want for transmission....

Honestly I don't know what to tell you, thats big project you have a head of you good luck

Doug

Thanx for your ideas.  I think I'll start looking fora Delco 6 pole from a Detroit diesel plant.  I have some time to find something more suitable than my 20 HP induction motor.  It's 575 volts at just 20 amps is very attractive though from a transmission loss consideration through modest conductor size.

1467
man of man, this group has some really (how should i say?) interesting? outside the box thinking? boardering on mad scientist? crazy guys!

just kidding, seems you have given alot of thought to this project, perhaps her is more to consider

1. keep you TSR down on these large blades, perhaps a tsr of 5 would be safe

2. design your tip speed to stay below that of supersonic,

3. consider a 3 blade prop, vibration on 2 blade props are troublesome, and yaw changes can get a bit wild.

4. get some engineering help on the tower, 1200#'s  seventy five feet up, in high winds, and blade loading, along with any vibration and yaw problems
can quickly destroy all you work, and maybe kill you or someone else

5. fence off at least a fall path , 75 ft radius from the tower , plus half the rotor diameter at least.

bad stuff happens to good people, hope to get to know you better, so don't get in a hurry and deal yourself out, ok?

i get nose bleeds on the second rung of a step ladder, no friggin way i am goin up a 75 foot tower.
but i know there are those that arent bothered by heights, hopefully you are one of those folks, cuz you may be spending some time up there.

good luck

bob g

Bob,

Thanx for the vote of cautioned encouragement.  You clearly have studied the subject of these machines and have addressed some fundamentally important issues to which I have answers.

#1.  As a matter of fact TSR=5 is the number I used in my design.  My work with small DIY blades (4 to 8 feet diameter) showed they worked nicely at a TSR of ~5.5.

#2. I forget the tip speed numbers but they were way below supersonic.  No worries here.

#3. The three blade is indeed preferable but would add as much as 400 lbs to my propeller and makes the pitch controlled hub much more difficult to build and also heavier.  Increased materials cost is a big negative as well.  By the nature of my design the hub and the blades can be swapped for different designs at any time via bolted flanges.  The hub will be a teetering style so as to hopefully eliminate the blade root fracture problem I saw occur on blades my neighbor made over the past several years which failed.  His machines were in the 500 watt class and less ambitious than mine.  One major reason for deciding on a servo driven yaw axis is to eliminate the jerky hunting that is a bad byproduct of a tail fin pointing system.  I have seen how two blade props really do have aggressive gyroscopic pulsing issues when being yawed.

#4.  You are right. I am seeking engineering consultation with my tower design.  I made a scale model of an earlier, less beefy concept and the model clearly showed the flex points and design weaknesses.  I will do the same for my final design.  Having as much as 3600 lbs way up there with the forces on it and the tower that you describe deserve respect!  I certainly don't want to be on the beast, or see a helper get injured in any way if it were to collapse.  I do not forsee operating the system in storm winds.  There will be an automated shutdown and safety stow protocol with wind signal of rapidly rising windspeeds detected by annemometer and also allowing human knowledge of storm coming and manual control.

#5. Where it will be placed the result in property damage of a catastrophic failure and collapse will be zero.

#6. Oops, there is no #6. ;)

Climbing is really hard for me now, not like before the (not my fault) highway head-on collission I miraculously survived almost 10 years ago and before that when I was younger climbing all over the big radiotelescopes. I don't like the heights either.  I recently saw a TV program about the Alberta oil sands project and in one scene a worker was being helped briskly up a tower ladder on the end of a wire rope winch hooked to his belt while he rode the ladder.  I will likely have to resort to a similar system to get up and down this beast.  I could weld a continuous T-channel up the middle of the ladder to facilitate the safety (anti fall) system of such a man lift scheme.

If this doesn't work I can replace the nancelle with a small deck and make a personal revolving restaurant with a terrific view!  ;D


1468
Waste Motor Oil / Re: Waste Motor Oil Refining
« on: July 31, 2006, 04:44:25 AM »
"I plan to try and let some - WTF - run through some in a sieve pan and see what comes out."

Well what the fuck do you think is gonna come out? LOL (WTF)

Peace&Love :D, Darren

That joke is pretty hard to resist!

You're not an agent with the BATF are you?  In the US the federal government has a bureau that takes Automatic Transmission Fluid very seriously!  They even carry guns and have the power to arrest dipsticks.   ;D

1469
Waste Motor Oil / Re: Waste Motor Oil Refining
« on: July 31, 2006, 02:42:37 AM »
we always burnt old engine oil as fuel, filter it gravity wise through fullers earth, then mix 50/50 with diesel, never had a problem.



I had to look up Fuller's Earth to learn what it is.  I wonder where I can purchase it.  One factoid I picked up was that kitty litter often contains Fuller's Earth.  Since I have cat litter here for my kitties I plan to try and let some WTF run through some in a sieve pan and see what comes out.  Thanx for the tip!

1470
Well if you can get the St up to 1800 rpm and hold it and drive the induction motorabout 1840 and hold it you should be able to generate some power...

Regulation is going to be a bear....
Your going to want a 3 phase ST, but you can't get a 575 3 phase unit I know I asked everyone in the buisness if they caould make them the Answere is no not for less than an order of 1000.

I think you might be better served by gettiing a compound fork lift motor, generate DC and using as much DC as possible for your needs along with a good inverter.
You might also consider a MG set with a DC machine ST head, batteries, large dump load, ect

Doug


Unfortunately i won't have 1800 RPM, except maybe just before launch. :o    From the reduced speed operation I've experienced often with my VW plant run at 1200 RPM  instead of 1800, I could probably count on 2/3rd's power spinning a 30 kW 4-pole ST head at 1200 RPM, so I'd see 20 kW at 45 Hz and reduced voltage.  Trouble is that 2/3rds speed is not normal and will only occur on really windy days.

The oddball low voltage I'd get is not an insurmountable problem as I can place a step up xfmer at the base of the turbine tower.  Such a transformer would have to be huge though, a way derated 60 Hz model and with custom placed taps.  These xfmers are not particularly cheap so I'd be better planning on a Marathon or something.  I'd like to find one of the Delco's from a 2 or 3-71 Detroit genset.  They are 6 pole and run at 1200 RPM.

I have a 1800 RPM, 20 kW DC generator that makes 50 VDC at 400 amps continuous so could probably make 30 kW in a cold winter wind.  Troubles are the speed and the need to run 2000 feet of 500 MCM cable to where I could use the power.  I do not want to have to purchase controlling interest in Canada Wire & Cable plus a small fortune on batteries or a large inverter, so once again I'm back to biting the bullet and getting a proper 6 pole ST head.  This is academic anyhow since the big DC machine is to be mated to (probably) a large Changfa as a welding machine here for the shop.

A traction motor is a good idea if I wanted DC, but I don't.  I do have a small one here now that is 36 VDC at 90 amps and 900 RPM.  That's only 3+ kW and it is huge and heavy.  A suitable one would be huger and heavier.  What kind of forklift will source a 20-30 kW motor?  That must be a monster!  Just call monsterlifttrucks.com ;)

You mention MG sets.  Those are horribly inneficient at about 50%.  I am going to a lot of trouble to make this electricity.  I don't want to throw half of it away.  Thanx for your thoughts.

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