Storing Cookies (See : http://ec.europa.eu/ipg/basics/legal/cookies/index_en.htm ) help us to bring you our services at overunity.com . If you use this website and our services you declare yourself okay with using cookies .More Infos here:
https://overunity.com/5553/privacy-policy/
If you do not agree with storing cookies, please LEAVE this website now. From the 25th of May 2018, every existing user has to accept the GDPR agreement at first login. If a user is unwilling to accept the GDPR, he should email us and request to erase his account. Many thanks for your understanding

User Menu

Custom Search

Author Topic: FEMM simulation showing COP 3 and 7  (Read 74768 times)

exnihiloest

  • Hero Member
  • *****
  • Posts: 715
Re: FEMM simulation showing COP 3 and 7
« Reply #75 on: February 09, 2011, 09:22:42 AM »
The forum may not be @broli's own forum but the truth is it is infested with arrogant incompetents such as @exnihiloest.
...

No progress, omnibot? Always in ad hominem attacks?
Time for you to consult a psychiatrist.
http://tinyurl.com/yk4oyj8


exnihiloest

  • Hero Member
  • *****
  • Posts: 715
Re: FEMM simulation showing COP 3 and 7
« Reply #76 on: February 09, 2011, 09:29:13 AM »
Like I said, the sims are correct in their OU conclusion because it coincides with the results from the experiment, as already seen.

There is no positive results in any experiment, allowing to conclude OU.



broli

  • Hero Member
  • *****
  • Posts: 2245
Re: FEMM simulation showing COP 3 and 7
« Reply #77 on: February 09, 2011, 09:35:28 AM »
Holy mother of trolls. Attention lacking much?

I just asked Stefan for moderator privileges over this thread. If I were you I'd start preparing that wonderful free speech and exit strategy speech.

spinn_MP

  • Full Member
  • ***
  • Posts: 224
Re: FEMM simulation showing COP 3 and 7
« Reply #78 on: February 09, 2011, 10:09:14 AM »
No progress, omnibot? Always in ad hominem attacks?
Time for you to consult a psychiatrist.
http://tinyurl.com/yk4oyj8

He's already under psychiatric "surveylance". Poor man actually suffers from a "Dunning-Kruger" effect..
http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect

Quote
The Dunning–Kruger effect is a cognitive bias in which unskilled people make poor decisions and reach erroneous conclusions, but their incompetence denies them the metacognitive ability to appreciate their mistakes.[1] The unskilled therefore suffer from illusory superiority, rating their ability as above average, much higher than it actually is, while the highly skilled underrate their own abilities, suffering from illusory inferiority. This leads to the situation in which less competent people rate their own ability higher than more competent people.

Omnibus is probably a synonym for an "extremely incompetent gibberish", which also happens to be one of his favorite phrases lately...

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: FEMM simulation showing COP 3 and 7
« Reply #79 on: February 09, 2011, 10:34:37 AM »
@Low-Q, restrain from offering advise on matters you have limited or no understanding. @broli's calculations are correct, the efficiency (not COP) is indeed greater than 1 and it is supported by experiment. The problem is that the OU is so low (as low, if not lower, as in most of the studied constructions) that even the best workmanship would hardly end up
 in a working device. Some new concept, a real breakthrough is needed which would bring about greater OU needed for making a real working device.
You are right about this. However, I was just telling broli my experience with FEMM. I have also designed several "COP > 1" designs in FEMM - untill I discovered that the working space affected my results greately. It is important to understand the limitations which can misguide the designer to believe that the results are correct. What harm can be done to brolis FEMM experiment IF he tried to follow my advice?
brolis design are hopefully correct, but putting limitations to any input from other members, or force people to shut up, at overunity.com isn't your job.

Vidar

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: FEMM simulation showing COP 3 and 7
« Reply #80 on: February 09, 2011, 10:40:54 AM »
This depends on your boundary conditions. I've used the mixed BC just like in that famous FEMM tutorial, 1/uo*R*mm where R is the radius of the boundary in mm. The calculation of force is quite far from this boundary especially for the magnets. You can actually see the paths for the force calculation.

And again calculating force or "work" on a stationary object is meaningless. I have no clue why this is even mentioned.

The simulation files have been posted, if you think there's something wrong with it I'd like to see your "corrected" results. It's easy to criticize, but contributing is something else.
Thanks for the feedback @broli! I will try this experiment myself - under your conditions, and mine.
Btw. It wasn't meant to be negative critizism in my post. I just shared my experience about FEMM, which might disturb the results greately. I think such feedback are important. Who knows how much experience you got with FEMM? I didn't. Therefor my little advice. I hope you understand :)

Edit:
Quote
And again calculating force or "work" on a stationary object is meaningless. I have no clue why this is even mentioned.
You're right, provided that the "stationary" object never changes position.


Vidar

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: FEMM simulation showing COP 3 and 7
« Reply #81 on: February 09, 2011, 12:28:53 PM »
I did a test in FEMM. It looks like the net energy required to move the steel bars out and in are pretty much regardless of position of the magnets. The next test is to see the energy required to move the magnets back and forth in one complete cycle.

Vidar

Low-Q

  • Hero Member
  • *****
  • Posts: 2847
Re: FEMM simulation showing COP 3 and 7
« Reply #82 on: February 09, 2011, 04:44:18 PM »
I get COP 12... but that is calculated in only 4 positions:

1 - Initial alignment,
2 - Magnets close to eachother
3 - magnets close + iron bars separated
4 - magnets in initial alignment + iron bars separated.

All forces are calculated as average between those positions, and the distances varies with 20 units on the bars, and 104 units on the magnets.

When I got more time I will take more samples to get a better average.

Vidar

broli

  • Hero Member
  • *****
  • Posts: 2245
Re: FEMM simulation showing COP 3 and 7
« Reply #83 on: February 09, 2011, 04:47:52 PM »
I get COP 12... but that is calculated in only 4 positions:

1 - Initial alignment,
2 - Magnets close to eachother
3 - magnets close + iron bars separated
4 - magnets in initial alignment + iron bars separated.

All forces are calculated as average between those positions, and the distances varies with 20 units on the bars, and 104 units on the magnets.

When I got more time I will take more samples to get a better average.

Vidar

I suggest you use a lua script. I'm pretty sure that 12 will converge down to a lower value with more steps.

Omnibus

  • elite_member
  • Hero Member
  • ******
  • Posts: 5330
Re: FEMM simulation showing COP 3 and 7
« Reply #84 on: February 09, 2011, 05:34:32 PM »
@broli,

You mentioned earlier you have an idea for a more efficient construction. Probably it would be a good idea to have @lumen try it with his Maxwell3D.

Omnibus

  • elite_member
  • Hero Member
  • ******
  • Posts: 5330
Re: FEMM simulation showing COP 3 and 7
« Reply #85 on: February 09, 2011, 05:42:01 PM »
Funny how those incompetent in physics such as @exnihiloest and @spinn_MP are now trying to be taken seriously as competent in psychiatry. Sorry @broli, couldn't resist.

broli

  • Hero Member
  • *****
  • Posts: 2245
Re: FEMM simulation showing COP 3 and 7
« Reply #86 on: February 09, 2011, 05:43:30 PM »
@broli,

You mentioned earlier you have an idea for a more efficient construction. Probably it would be a good idea to have @lumen try it with his Maxwell3D.

Don't know which design you actually mean, but now you mention it there is a 3d case I would like to see simulated. The one I posted on the first page:

http://www.overunity.com/index.php?topic=10316.msg273152#msg273152

This is not a cross section view but actually the setup. The stationary magnet has half of itself sticking out while the other half under the core. In FEMM I couldn't make the 3d transition, but the force was lower when the magnet approached the stationary from between the cores than when it left. In a true 3d simulator this by passing can be achieved.

Might be wishful thinking as it completely eliminates opening the cores AND is a continuously rotating setup. But you never know. Below is another example of just a linear case.

Omnibus

  • elite_member
  • Hero Member
  • ******
  • Posts: 5330
Re: FEMM simulation showing COP 3 and 7
« Reply #87 on: February 09, 2011, 06:00:00 PM »
If opening the cores can be eliminated somehow that would increase efficiency. However, I don't quite see how that may be achieved since it is an essential part of restoring the initial state or so it seems.

phoneboy

  • Jr. Member
  • **
  • Posts: 97
Re: FEMM simulation showing COP 3 and 7
« Reply #88 on: February 10, 2011, 12:38:58 AM »
@ broli, just saw something over @ energetic which could be used to separate your discs @ the appropriate time check this link: http://www.correlatedmagnetics.com/MovePath.html. Your linear design with the half shrouded magnet is very similar to the linear one I posted on page one, an air gap seems to be the key.  Here's an animated gif of the flux path hope it helps.

gravityblock

  • Hero Member
  • *****
  • Posts: 3287
    • Get Dish Now! Free Dish Network System from VMC Satellite
Re: FEMM simulation showing COP 3 and 7
« Reply #89 on: February 10, 2011, 05:00:16 AM »
It's pretty obvious looking at Butch's videos there can be a gain from this concept.  I don't know why the sims are even needed to show this effect.  It's like we compute 2+2=4 in our head, but yet we need to use a calculator to convince people that 2+2=4.  The sims and the calculator step should have been un-neccessary from the very beginning.  We need to design and build, instead of debating the sims.

GB
« Last Edit: February 10, 2011, 04:14:29 PM by gravityblock »