VAWT - large sail - exciting experimentation

[OzPete51]

Hi Guys,

I have built a number of VAWT prototypes. I am achieving lots of torque with about 45rpm at 12kph winds with 10sq meter sail areas. My Vawt is similar to US PATENT 5525037 dated june 1996. http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fne



tahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=5525037.PN.&OS=PN/5525037&RS=PN/5



525037

The big issue is power generation. Due to the nature of wind fluctuating - and the requirements of generators to have fixed hi revs with plus or minus 10 percent tolerance I am looking at alternate methods.

One idea is steam. If a turbine could heat water to generate steam, it would provide a simpler system to link multiple VAWTs. The steam could also be directly employed to heat my home - provide hot water - drive compressors to provide air conditioning and refrigeration - as well as drive a steam turbine to provide main power and dump surplus to the grid.

I am experimenting with rotating cavitation drum water heaters to heat the water.

Has anybody else gone this route with VAWTs?

Sample of water cavitation heater can be found at http://www.youtube.com/watch?v=yh_-DUKQ4Uw&NR=1

[electrondady1]

the only board member to have worked on both vawts and cavitation heaters is

windstuff ed.

i am not sure is he has put them together .

[Norm]

Oh....OH! This Sample of water cavitation heater

More energy output than input....Overunity....

bad word....

   Then you are thinking about making steam to

heat your home? hot water is more efficient....

   

[windstuffnow]

  It's highly unlikely you'll get more BTU out than you put in, I've built a couple of them and both seem to around 80% efficient.  In order to run them slow and produce steam the diameter will have to be fairly large or build a smaller diameter and gear it to the speed you need.  

  The best one I built, small 4" diameter with 120 holes, requires 6500 rpm to start the cavitation process.  The patent states in order to make steam, for home heating, it would require an 8 to 10" diameter rotor running at 3500 rpm and would require 7 hp.  My small one will bring the water to 200 degrees in less than 5 minutes running...

The rotor shown above has only 60 holes and ran quite nicely at 180 degrees with a 2hp input of 6500 rpm.  I had to experiment with the fan flow rate through the radiator to keep the temp reasonably constant.  I calculated it was doing around 4000 BTU constant and the watt meter was showing a continuous 1500 watt draw.   It's not enough to heat a house by any means but it does nicely as a room heater.  Not very practical for a  room heater unless the input was achieved through alternate methods.

I plan to build an 8" diameter in the future when time allows with the intentions of connecting it to a wind turbine.  

.

 

[OzPete51]

Hi Norm,

I don't care about over unity - I just want efficiency greater than 30 percent.

This should be better that converting windpower to electricity and then using electricity to heat water - less than 30 percent efficient or so i'm told.

yes. i think you are right about using hot water as opposed to steam to heat the home - this will naturally happen as i will have a lot of hot water in storage waiting for wind to pick up to convert a portion of it to steam. This will be my battery!

cheers OzPete

[OzPete51]

Hi windstuff Ed,

Wow! I am hugely impressed by your effort with the water rotor you have shown. I know the work that goes into drilling such perfectly aligned holes and I thank you for sharing your results. I am requiring only 30 percent or greater efficiency - and I have limited machine shop capabilities so I am looking at simpler options such as using the tesla turbine concept with minute bumps or trenches on disks that create a harmonic to help thump the stuffing out of the water to convert it to steam. Don't know if anyone else has done this so I will advise if I have any success. Alternatively - using pre perforated sheet metal as a drum saves a LOT of work - but may be more difficult to cavitate properly. As another thought using electrolysis on the spinning perforated drum also creates heat - using this effect and burning the hh0 mix that results to further heat the water is something else to try. Thought - what happens if the harmonics of the ac used in the electrolysis tie in with the harmonics of the cavitation? Beware hho is a dangerous mix - please be careful - water-traps MUST be used!

Thankyou for the positive response, I was not expecting to find such similar thinkers and look forward to swapping further ideas and results with you.

Cheers

OzPete

[OzPete51]

Thanks electrondady1,

cheers

ozpete

[vawtman]

Hi Ozpete

 Well the wind turbine spins for free once built.Its hard for me to imagine a wind turbine outdoors with pipes running indoors for storage.

 I still think feeding elements is the best route.

 You seem to be from OZ though.

[vawtman]

Oh forgot any pics of the turbine?

[windstuffnow]

  I had thoughts of using discs with holes drilled through and staggared to beat the water.  This would be far easier to make the main rotor and in any diameter.  It would also make the unit much thinner.  

  I'm working on a major project right now and I believe its going to be a while before I can start on anything new.

.

[OzPete51]

Hi Vawtman,

I cant show my actual windmill (prov patent only) but I can show an earlier prototype animated gif I made - here tis http://www.otherpower.com/images/scimages/8568/animatedgif.gif.

This turned out to be a 2001 patent already in existence see http://www.otherpower.com/images/scimages/8568/au2002214421_Page_2.jpg.

My current windmill has similar performance.

If Vawt energy can be converted to hot water with greater than 30 percent efficiency it would be more efficient than my current method of driving a generator with a 100 to 1 gearing and dumping the power to a heating element in my hot water tank.

This would also make using multiple VAWTs easy - they would simply add to the hot water storage near the house with insulated piping. Much simpler than linking multiple generators with variable wind complicating things.

Cheers

OzPete51

[vawtman]

Ozpete,

 You say"My current windmill has simular performance"

 I dont see any performance though.Hmmm One could make a clothsline spin in the wind.Hmmm again,could patent that.

 What type generator are you driving into your water tank at that ratio?

 Vawts are fun no matter what shape or size and the fun part is "matching the load"

 Saying by Flux that sticks in my head.

 Ed{windstuff} is also a great mentor here.

 Take your time and have fun.

 Mark

[OzPete51]

Hi Mark (Vawtman),

Imagine 3,4,5 or 6 x 10 sq meter sails turning at 6-10 rpm in 12kph winds and you would have a good picture of my system. The 12v bosch car alternator (800rpm) cuts in when the winds are about 20kph - but the gearing system I am using is a temporary job and I am sure I can do better. (Pulleys and V-Belts).

If Ed is listening I am extremely interested in the Friction heater discussions in OTHERPOWER around May 2003  and  also the Eddy current water heater discussions around nov 2007

The 2003 discussions described a system

Posted By: Ed <elenz(at)windstuffnow(dot)com> Date: Monday, 26 May 2003, at 5:06 p.m.

In Response To: Re: Friction Heater (Mike)

I've built a small one to test and experiment with. There is no free ride so to speak. If you put 500 watts into it you'll most likely get somewhat less out. The small unit took about 20 minutes to come up to 140 degrees and maintained that temp continuously throughout the tests. A better and simpler way to do the same thing is use a magnetic disc, similar to those being used to produce power, run it in close proximity to a copper, aluminum, or brass plate and you'll get hotter temps from it. A small model had a copper plate with copper tubing soldered to the back and ran at 250 rpm heated 5 gal of water in about 5 minutes to 140 degrees. Either way what you put in is more than your going to get out. On the other end of it, if you drive it with a vertical wind turbine... the heat is free...

Have Fun! Ed

[new] Re: Eddy current water heater (3.00 / 0) (#2)

by windstuffnow (elenz(at)windstuffnow(dot)com) on Tue Nov 7th, 2006 at 04:17:23 PM

MST

(User Info) http://www.windstuffnow.com/main

Rods diagram would work better but if you soldered the tube to a copper plate you'd

get much more heat from it.

I've built one that way and it will heat 5 gallons of water from 70* to 140* in under 10 minutes at approximately 200 rpm. The test disc was 8" in diameter and had 12

magnets on it and was driven by my lathe. I had a small circulation pump on it as well.

They work pretty good. I've only played with it on a small scale so far but I'd bet a large unit driven by a VAWT would produce some decent hot water. Just another one of my circular projects ( 'round to it )

.

Have Fun! Windstuff Ed

And of course the amazing Cavitation heater that is shown earlier in this subject discussion. I must say Ed, you amaze me, and set a standard that it truly world class.

I guess I am most interested in the Eddy heater, as it seems to be the simplest to replicate. (named after Ed?)

I have tried experiments on an aluminium strip (15mm x 3mm) and  the best results in heating  appears to be when two magnets are each side of it and the strip is moved through the lines of attractive force. Placing the Magnets only on one side seemed to have little or no heating effect. I did not succeed in trying multiple magnets reversing the polarities as for this exercise I ran out of hands.

If I am correct the 12 magnets are placed on one disk (aluminium?)in NSNSNSNSNSNS using epoxy glue and the stationary second disk (copper) has the copper tubing soldered to it. The 8 inch diameter aluminum disk rotates at 250rpm and the stationary 8 inch copper disk is as close as possible to the spinning magnets.

If you are reading this Ed, is this the best method to try, and do you recommend neo magnets?

Cheers

OzPete