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Author Topic: Is the Tesla turbine "better"?  (Read 17928 times)

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #25 on: 12/06/2009 01:17:40 »
Tesla did a variety of different things, many of them were spark-gap, but even then usually filtered through a very high-q filter, so no, not really; if you filter a spark gap enough you no longer have a spark gap transmitter, as it only radiates in the pass band- the really evil thing about true spark gap transmitters is that they radiate indiscriminately.

At least one of Tesla's experiments involved a steel wire oscillating at a lofty 50khz(!) in a magnetic field, and using that as his oscillator. Given the lack of valves, he went much further than anyone in producing practical systems.

I think if you read the wikipedia page:

http://en.wikipedia.org/wiki/Invention_of_radio#Tesla

Tesla comes out pretty well in comparison with everyone else. Even Marconi, who is often credited with inventing radio got most of his stuff from Tesla, and his famous experiment is now rather in doubt. And in America at least, his patent was finally overturned in favour of Tesla.
« Last Edit: 12/06/2009 01:20:46 by wolfekeeper »
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #26 on: 12/06/2009 17:41:07 »
The Tesla turbine seems simple...
..What do you think? What is the great benefit if there is one?
Well there is this (NSFW)!!!!:

http://ladycartoonist.com/archives/34
 

Offline Karsten

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Is the Tesla turbine "better"?
« Reply #27 on: 12/06/2009 20:50:14 »
To get back to the turbine:

I was told that Tesla invented this turbine and it could not be made to work well at his time for lack of materials. Today those materials exist and the technology for the turbine is SUPPOSED to be superior. There was some talk about superhigh revolutions that could not be managed with materials of Tesla's time. I gather they were talking about larger turbines than the one mentioned in the post above.
 

Offline Karsten

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Is the Tesla turbine "better"?
« Reply #28 on: 12/06/2009 20:51:39 »
The Tesla turbine seems simple...
..What do you think? What is the great benefit if there is one?
Well there is this (NSFW)!!!!:

http://ladycartoonist.com/archives/34


Where are the tubes that allow the gases to flow into the turbine? How are they exhausted in a way that is not distracting to the user? This is not a "cordless" device, I assume. Does the vibrator not get rather hot when operated with steam?

Nice machining job though.
« Last Edit: 12/06/2009 20:53:53 by Karsten »
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #29 on: 12/06/2009 21:03:15 »
I presume that the steam goes in at the little plug thing on the side and out through the vents.

It would be a bit scary though with steam like that I would think. Compressed air could be more appropriate.
 

lyner

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Is the Tesla turbine "better"?
« Reply #30 on: 12/06/2009 22:28:07 »
wolfekeeper:
The spark transmitter.
How would Tesla have measured the "High Q" of his resonator if he hadn't access to cw oscillators? If you don't use an active device (valve etc) and a good filter / matching sircuit I can't see how you would get narrow bandwidth plus reasonable power out of a transmitter. What was the state of filter design in those days? The maximum frequency used for his experiments would have had to be in the order of hundreds of kHz. You'd be lucky to get more than a couple of channels to work over a useful distance without mututal interference problems.
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #31 on: 12/06/2009 22:46:01 »
wolfekeeper:
The spark transmitter.
How would Tesla have measured the "High Q" of his resonator if he hadn't access to cw oscillators?
It's not that difficult to calculate. Inductance, resistance and capacitance. Heard of them? Tesla had. I don't know how he did it, but you can measure currents using coils and magnetism; it's usually called a 'meter'.
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If you don't use an active device (valve etc) and a good filter / matching sircuit I can't see how you would get narrow bandwidth plus reasonable power out of a transmitter.
I'm sure it was pretty inefficient, but it doesn't matter.
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What was the state of filter design in those days?
Tesla was the state of filter design in those days!
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The maximum frequency used for his experiments would have had to be in the order of hundreds of kHz.
Yup, his Tesla coils were up to a few meg.
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You'd be lucky to get more than a couple of channels to work over a useful distance without mututal interference problems.
A lot of his stuff did have *very* high Q, so not as bad as you might think.
 

lyner

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Is the Tesla turbine "better"?
« Reply #32 on: 12/06/2009 23:01:47 »
Efficiency isn't all that counts - it's actual Power! He didn't have many hundreds of Watts of DC available (ok, perhaps 1kW) and the 'coherer', which was all they had as a detector, was pretty insensitive. The only thing in his favour would have been the lack of other transmitters to interfere with his experiments.

Measuring Q: Yeah but if you haven't worked out the effect Radiation Resistance of the antenna, how can you tell what the resistance (gives Q)  is? You can't just measure the DC resistance - that's an entirely different thing. Even now, you have to do it numerically for  RF inductors.

Sorry, but, techincally, you are into the realms of farmyard products. To "RF with a "meter" you need a diode - did he have thermionic diodes? No. He had to use a coherer.

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Tesla was the state of filter design in those days!
That's not an answer. I was interested to know what the actual state of knowledge was. Filter theory is actually quite a recent development. (First World War ish)

Why does he have to have been a superman? Don't make out he had done everything. Get him into perspective.
« Last Edit: 12/06/2009 23:06:30 by sophiecentaur »
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #33 on: 12/06/2009 23:15:09 »
Efficiency isn't all that counts - it's actual Power! He didn't have many hundreds of Watts of DC available (ok, perhaps 1kW) and the 'coherer', which was all they had as a detector, was pretty insensitive. The only thing in his favour would have been the lack of other transmitters to interfere with his experiments.

Measuring Q: Yeah but if you haven't worked out the effect Radiation Resistance if the antenna, how can you tell what the resistance (gives Q)  is? You can't just measure the DC resistance - that's an entirely different thing. Even now, you have to do it numerically for  RF inductors.
Tesla is known as somebody who actually measured skin effect. Gee I wonder why/how he did that?
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Sorry, but, techincally, you are into the realms of farmyard products. To "RF with a "meter" you need a diode - did he have thermionic diodes? No. He had to use a coherer.
No, he also had spark gaps. You can get a very good idea of voltage and resonance with calibrated spark gaps.

You keep jumping to these fantastic conclusions; like to measure X, you need a digital multimetre, and there's no other way to measure it!!!! Therefore he's a crank... blah blah blah.

Really, there is more than one way to skin a cat. Just because you know only one way, doesn't mean that's the only way.

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Tesla was the state of filter design in those days!
That's not an answer. I was interested to know what the actual state of knowledge was. Filter theory is actually quite a recent development. (First World War ish)
Well, probably in the full glory. But Tesla knew from mechanical experiments quite a bit about resonance. I read about how he would set different pendulums swinging and stuff like that. I'm sure he wouldn't have been able to work out the interference between two tuned circuits, but then again, he could build two circuits and try it.
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Why does he have to have been a superman? Don't make out he had done everything. Get him into perspective.
I'm the one that has got him in perspective. You're the one that's accusing him of being a talentless quack that never did anything worthwhile. Anything that he actually did, you claim that it was impossible, that there's no way to do, that it was all made up.

To build a Tesla coil, you primarily need a couple of tuned coil with high Q (a few hundred). He invented this. He didn't just do it by sheer luck. Your attitude that he couldn't have done it, is really, very, very funny indeed.
« Last Edit: 12/06/2009 23:17:37 by wolfekeeper »
 

lyner

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Is the Tesla turbine "better"?
« Reply #34 on: 13/06/2009 15:42:48 »
"calibrated spark gaps" eh?
I guess they would be very frequency sensitive. Their  striking voltage at DC could be different from the voltage at 1MHz. They would, undoubtedly work 'in principle' but what point are you trying to make? No one uses them now because they aren't very good. They were a first stab at the problem- that's all.

Didi you take my point about measuring Q at RF?

Who mentioned a Digital Multimeter? They have only been around for a few decades and no better in principle, than a good moving coil meter for many applications.

I never said that Tesla didn't invent the Tesla Coil. That would have been daft, wouldn't it? I said that the spark communication system did nothing more than prove a point.

He may well have been able to detect a spark transmitter radiating a short distance away using a resonant circuit. If that constitutes a useful form of communication, then well done to him.
The point about spark transmissions is that the transmitted signal, by its very nature, is broad spectrum. If you use a narrow transmit filter (to avoid putting out interference) then you reduce the transmitted power pro-rata. It rapidly becomes less and less worth while to use the technique, the more channels you want to use. It's classic communication theory.

The output filter for a transmitter using a carrier wave can be very sloppy because the power spectrum is defined by the drive oscillator. I'm not sure what the argument is all about.

Looking through my posts I can't find the words "talentless" or "quack". Where did you read them?
I have no argument at all with the dear Nicola. My argument is with the fan club who want him to be the Messiah and not a very naughty boy.

Why go for Tesla when there are names like Helmoltz and Heaviside (contemporaries of his) whose formulae and principles are still in daily use? They gave him a Unit in his honour, what more do you want?
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #35 on: 14/06/2009 01:59:14 »
I can find no reference to spark gaps being frequency sensitive. Do you have a reference?
 

lyner

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Is the Tesla turbine "better"?
« Reply #36 on: 14/06/2009 11:44:06 »
No particular reference, it's just that, in general, the ionisation of a gas and the fields around an object are sensitive to frequency. The striking voltage would certainly be related to a combination of peak field, mean field, and recombination rates.  You couldn't be sure of your calibration. But, I'm sure Tesla had an idea about that and would have treated his measurements more realistically than  his enthusiastic followers have, apparently.

You see, as he wouldn't have had access to a signal generator, he would need to have been using narrow band filtered spark signals (effectively, noise) to explore the characteristic of his wider band filter.  Personally, I can't see that he would have had any accurate idea of the Qs involved. To predict the Q of a resonant circuit coupled to a radiator, you actually have to know how much energy is being radiated - to give the radiation resistance. For anything other than a half wave dipole this is difficult and this, amongst other things, makes me doubt that he would have known (or cared) too much about the finer points of his experiment. I don't know what the state of antenna theory  was when he was using sparks - pretty poor I imagine - there were no antennae which needed analysing until people started using proper transmitters!
He achieved 'wireless' transfer of energy / information in the only way he had available at the time. I have never said that was not a good thing. I have always said that it needs to be seen in proportion. To do that, it may be necessary to know a bit about RF Engineering since his time.
« Last Edit: 14/06/2009 12:05:12 by sophiecentaur »
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #37 on: 14/06/2009 15:36:56 »
You see, as he wouldn't have had access to a signal generator, he would need to have been using narrow band filtered spark signals (effectively, noise)
The words you're looking for is 'impulse response' A spark is an impulse.
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to explore the characteristic of his wider band filter.  Personally, I can't see that he would have had any accurate idea of the Qs involved.
You know what? Dunno. And I am completely sure you don't know either what he could and couldn't do, given the technology of the day.

But, given what he did achieve, building powerful Tesla coils, he did indeed achieve high Q; and using his Tesla coils it would have been very obvious when Q went up, and Q went down.
 

lyner

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Is the Tesla turbine "better"?
« Reply #38 on: 14/06/2009 17:46:40 »
An how do you suppose Mr Tesla would have measured the "impulse response"? Accurate time domain analysis at RF didn't come into the picture until they invented the Oscilloscope.

In fact, he used continuous sparks, didn't he? That is a very rough type of noise. Rather hard to analyse at all, actually.

I am not sure whether you appreciate what Q means. It represents the rate of power loss compared with the reactive power in the circuit. If you want to extract power out of a resonator, you can't have a high Q - because Q is an inverse measure of the energy leaking out. Before the corona starts at the top of the Tesla Coil, the system has a higher Q than it does once it has started.

I just remember that, when I used a transmitting valve as the power source for a Tesla Transformer, then it was delivering very impressive arcing, the valve used to nearly melt itself. The coupling with the outside was very much affecting the transformer circuit. It would have been the same with the primitive spark design.

Just because we have no direct evidence about what he measured an how, we have no reason to assume that he was doing anything particularly accurate. It would not have mattered for the purposes of producing his demos.

What "power" did his "powerful" coils produce? Do you know? In a darkened room with the right stage management, a moderate spark could have looked pretty impressive.

What was his primary power source?

But you said it all with your "given the technology of the day" phrase. He did what he could and no more.
 

Offline wolfekeeper

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Is the Tesla turbine "better"?
« Reply #39 on: 14/06/2009 18:23:16 »
An how do you suppose Mr Tesla would have measured the "impulse response"?
I don't think he did. The scientific position is that macroscopic systems like impulse responses exist whether or not you measure them.
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In fact, he used continuous sparks, didn't he?
No, all Tesla coils use an intermittent breaker system.

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That is a very rough type of noise.
No. Tesla coils are driven by impulsive excitation.

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I am not sure whether you appreciate what Q means. It represents the rate of power loss compared with the reactive power in the circuit.
Really? I wasn't aware of that. At all. Thank you for sharing your awesome knowledge. No, really. I mean it. Honest. Thanks.
 

lyner

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Is the Tesla turbine "better"?
« Reply #40 on: 14/06/2009 23:33:21 »
His sparks could not have been 'impulses' they were bursts of energy, from some form of induction device, which would involve an LC resonance - the classic Rumkorff(?) induction coil, no doubt, but beefed up.  He would have been using bursts of very mucky RF (bursts if noise modulated carrier, would be one way of looking at it)  from his exciter.  He was stuck with this rather than cw because he didn't have a Valve to use. With a cw transmitter to drive the primary, you get a cleaner spectrum and much better performance. The coil is still a 'tesla coil' - it's just a more modern incarnation.

Why introduce the term "impulse response" as if it was relevant to Tesla's measurement capabilities. I don't see, remotely, how it could have been.

A good example of how to get an indication of the Q of an oscillator is to count the number of swings of a pendulum to where they get to 1/e of their original amplitude. (i.e. half energy). Fine with slow mechanical oscillations but harder to do with a burst of RF. You can see it on an oscilloscope though, for a resonant RC circuit, when you disconnect it from its exciter oscillator.
 

Offline Vasyl

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Re: Is the Tesla turbine "better"?
« Reply #41 on: 27/04/2016 20:15:21 »
A big advantage of Tesla turbine is cost and simplicity. But, in spite of the fact that turbine consists of a set of smooth disks; efficacy of turbine depends on spacing between disks. Spacing between disks has to be as close as possible because a fluid drags on the disk by means of viscosity and the adhesion of the surface layer of the fluid. Typical gap is less than 0.5mm that means the disks have to be extremely smooth and spacers between disks have to be very precision too.

To my mind, it would be easier to make turbine with two cones – see attached pictures. Such turbine also works by means of viscosity and the adhesion of the surface. But, in contrast to Tesla’s turbine, such turbine has self-alignment gap. If there is not fluid between cones then gap is zero. When we are feeding turbine with fluid then inner cone is going up and revolving. Also such turbine doesn’t have problem with bearings because it steams over a fluid.

To get electricity, permanents magnets can be inserted in inner cone.
As example, I built very simple prototype which can be made in 5min. For this you need 2 flowerpots and air from vacuum cleaner. You can watch it on my video.
feature=youtu.be
Also if we have bigger air pressure then we can decrease gap by setting heavier inner cone that gives more power. Also surface of cones has an influence on lifting force because force depends on air pressure and the surface on which the air presses.     
 

Offline syhprum

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Re: Is the Tesla turbine "better"?
« Reply #42 on: 03/05/2016 22:28:15 »
I believe that spark transmitters were employed in some German anti aircraft radars in the 1940,s
 

Offline Michael Miles

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Re: Is the Tesla turbine "better"?
« Reply #43 on: 17/10/2016 08:27:19 »
Tesla turbine was a rotary design which with the use of disks reduced the shock of the blade because the attack was parallel and not a steep angle. Adhesion is the force that was used and not the standard push, pull. No vibrations meant that maintenance was easy and the ability to adhere the substance used made for a quiet run. Very efficient.
Tesla was quite possibly one of most intelligent people our planet has seen and if JP Morgan was not involved we would all be using free electricity right now. The wireless transmission of power that was collected from our stratosphere means all would prosper. Evil men can't make slaves of the world this way. Patent or no patent when men have the method but hide it so they can make money must stop. Kind of like the Federal Reserve. Useless and must be abolished.
Haarp is now the weapon in use from the Tesla Tower. Leave it to evil to use good for bad
"Evil succeeds when good men do nothing"
 

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Re: Is the Tesla turbine "better"?
« Reply #43 on: 17/10/2016 08:27:19 »

 

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