Author Topic: Joule Thief 101 (Read 946885 times)

tinman · « **Reply #510 on:** February 29, 2016, 01:46:53 PM »

Quote from: MileHigh on February 28, 2016, 07:54:06 PM

MileHigh

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Sure, let's take the swing as an example but let's get real about it and also talk about a real output. Without having a real output you are just spinning your wheels and going nowhere.For starters, resonance is simply a method for storing energy. So you have to put energy into the resonant system, and by definition take energy out of the resonant system if you are going to accomplish something.
What you can't do is not keep your eye on the energy ball, and I don't think either of you are doing that properly.

I dont think you grasp the reasoning behind resonance. The reasoning being much the same to that of having the timing correct in an ICE engine-done for best performance.

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The child is at rest on the swing. You give him regular pushes of 20 joules. The swinging gets higher. The child's swing energy goes something like 20 joules, 40 joules, 60, 80... 180, and then finally there is 200 joules of energy stored in the swinging. Energy that you put there by pushing on the child. So far the output is zero.

Now that the child is swinging high, let's factor in the air resistance. Let's say the child loses 5 joules per swing. So that means you only have to push with 5 joules of energy per swing to maintain the high swinging, and the output is still zero.

So, now let's talk about an output - you have to have an output. So let's say that next to the swing there is a hanging rope that loops down and the child is wearing a leather work glove in one hand and he grabs the rope during each down swing to slow himself down and burn off some energy. Let's say he burns off 30 joules every time he grabs the rope.

So, you push on the child with 5 joules, and he is one the way down with 200 joules of energy in the swing. But this time he grabs the rope and when he comes back to you on the reverse swing there is only 165 joules in the swing. So that means that this time you can't get away with pushing with 5 joules because of "swing resonance magic," you will have to push back with 35 joules of energy to maintain the swinging.
Where is the "resonance magic" there?
When the child is swinging to output 30 joules you have to input 35 joules.
If there is no swinging and you just grab the rope and pull on it, to output 30 joules you have to input 30 joules.
Exactly the same thing will happen in an LC resonant circuit. The friction looses when swinging will be substituted for the i-squared-R losses in the wires.
So forget about your trampolines and your resonant frequency stuff, it means nothing. Look at the energy and you will find nothing special. It's just another wild goose chase down a garden path.

What has all this got to do with increasing the electrical efficiency of a JT type circuit by way of resonance?. I have not once mentioned that resonance will enable us to draw more out of such a system than we put in. You last lot of junk paragraphs seem to indicate that i was saying such a thing. There are a few types of resonance MH,and you seem to be stuck on one of them. JT switching is force MH,it is not resonant switching.

Brad

tinman · « **Reply #511 on:** February 29, 2016, 01:52:48 PM »

Quote from: sm0ky2 on February 29, 2016, 06:52:31 AM

this is always a possibility, with certain types of capacitors in certain situations.
Tantalum capacitors can be exploited in this manner.
I have not had a chance to play with these new "supercaps"
but it is indeed possible that they may under the right circumstances, display this phenomenon.
Some electrolytic capacitors are designed NOT to do this, for stability purposes.

Well if it is the cap that is some how self charging at this rate,then we had better look further into it,as the circuit has been cycling for two days now,without any meters or the scope hooked up to it-->to eliminate any chance that either may have been charging the cap. But as the cap dose not charge up with the circuit disconnected,then it's a sure thing it is not the cap that is self charging.

I connected a 10 meter length of wire as an antenna,and it made no difference at all to the charging rate???.

Brad

MileHigh · « **Reply #512 on:** February 29, 2016, 03:40:24 PM »

Brad:

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I dont think you grasp the reasoning behind resonance. The reasoning being much the same to that of having the timing correct in an ICE engine-done for best performance.

You have got to be kidding. For starters you are not explaining the "reasoning," you are just throwing the word around like spaghetti hoping it will stick to the wall. It's meaningless to say "reasoning" and then not actually state any reasoning.

Adjusting the timing of an ICE has absolutely nothing to do with resonance and there is no connection at all.

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What has all this got to do with increasing the electrical efficiency of a JT type circuit by way of resonance?

That is a meaningless statement based on blind belief with no substance. You can't even define "resonance" for a Joule Thief. If you claim that you can, then go ahead and define and explain it. Go ahead and define and explain the alleged increased electrical efficiency.

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You last lot of junk paragraphs seem to indicate that i was saying such a thing. There are a few types of resonance MH,and you seem to be stuck on one of them. JT switching is force MH,it is not resonant switching.

The paragraphs were not "junk," they clearly show that resonance has to actually mean something with respect to energy. You can't just throw the term around without it meaning anything. I made no reference to you whatsoever in my breakdown of a swing in resonance, it was purely a generic analysis.

Please go ahead and define the "few types of resonance" and state which "type" applies to a Joule Thief. How and why is it beneficial?

MileHigh

tinman · « **Reply #513 on:** February 29, 2016, 04:41:34 PM »

author=MileHigh link=topic=8341.msg475892#msg475892 date=1456756824]
Brad:

MileHigh

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You have got to be kidding. For starters you are not explaining the "reasoning," you are just throwing the word around like spaghetti hoping it will stick to the wall. It's meaningless to say "reasoning" and then not actually state any reasoning.

Not spoon feeding you any more MH.

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Adjusting the timing of an ICE has absolutely nothing to do with resonance and there is no connection at all.

Bullshit-it's the very same.
If the timing is out on either,then in both cases you turn your fuel(energy)into heat,in sted of doing what it should be doing in each case.

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That is a meaningless statement based on blind belief with no substance. You can't even define "resonance" for a Joule Thief. If you claim that you can, then go ahead and define and explain it. Go ahead and define and explain the alleged increased electrical efficiency.

About time you did some thinking of your own MH,but that seems to be fading fast for you.

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The paragraphs were not "junk," they clearly show that resonance has to actually mean something with respect to energy. You can't just throw the term around without it meaning anything. I made no reference to you whatsoever in my breakdown of a swing in resonance, it was purely a generic analysis.

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The paragraphs were not "junk," they clearly show that resonance has to actually mean something with respect to energy. You can't just throw the term around without it meaning anything. I made no reference to you whatsoever in my breakdown of a swing in resonance, it was purely a generic analysis.

Like i said,you just dont get it MH.
When will the wine glass break using sound waves to break it?
Oh thats right,when the wine glass vibrates at resonance with the sound waves-->but will not break either side of said resonant frequency.
If this dose not explain the importance and increase of efficiency due to resonance MH,then your a lost cause.

https://www.youtube.com/watch?v=BE827gwnnk4

Brad

MileHigh · « **Reply #514 on:** February 29, 2016, 06:19:48 PM »

Brad:

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Not spoon feeding you any more MH.

Don't even try to play a silly game like that. You like to talk the talk with a lot of meaningless statements that are cliches but apparently you can't walk the walk.

I asked you to explain the "reasoning behind resonance," which was your statement. So I said this: For starters you are not explaining the "reasoning," you are just throwing the word around like spaghetti hoping it will stick to the wall. It's meaningless to say "reasoning" and then not actually state any reasoning.

If you refuse to answer and state the "reasoning" in the "reasoning behind resonance" then you are just bluffing and have nothing to say. This statement from you to me, "I don't think you grasp the reasoning behind resonance" with respect to a Joule Thief is complete and total BS unless you explain the reasoning. Put up or admit that you can't back up your statement.

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Bullshit-it's the very same.
If the timing is out on either,then in both cases you turn your fuel(energy)into heat,in sted of doing what it should be doing in each case.

No, an ICE doesn't resonate in any way, shape or form whatsoever. It's not "the very same" there is no relation at all. If you talk about proper timing, then there is more of a connection between an ICE and a Joule Thief in normal operation. i.e.; the valves close at the right time just like the Joule Thief switches at the "right time."

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About time you did some thinking of your own MH,but that seems to be fading fast for you.

That's anther poor attempt as distraction and deflection. Another attempt to feign that I am the one that doesn't know what I an talking about instead of you backing yourself up and talking real substance about your silly claims.

I will repeat what I said: That is a meaningless statement based on blind belief with no substance. You can't even define "resonance" for a Joule Thief. If you claim that you can, then go ahead and define and explain it. Go ahead and define and explain the alleged increased electrical efficiency.

So go ahead and define "resonance for a Joule Thief." I don't think you can at all. Instead it's all bluster and blarney and BS. You are back to holding your breath and turning blue. So put up or say nothing and FAIL.

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Like i said,you just dont get it MH.
When will the wine glass break using sound waves to break it?
Oh thats right,when the wine glass vibrates at resonance with the sound waves-->but will not break either side of said resonant frequency.
If this dose not explain the importance and increase of efficiency due to resonance MH,then your a lost cause.

https://www.youtube.com/watch?v=BE827gwnnk4

I get it perfectly and so far you can't say a single thing to back up your statements. You are playing the same BS game that a typical "free energy magnet motor" guy plays.

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Oh thats right,when the wine glass vibrates at resonance with the sound waves-->but will not break either side of said resonant frequency.
If this dose not explain the importance and increase of efficiency due to resonance MH,then your a lost cause.

Big deal that the wine glass breaks at the resonant frequency. That has zero to do with a Joule Thief. What "increased efficiency" are you talking about? Define it please and relate it to a wine glass and a Joule Thief. If you can't do that then your statement is more BS. So far you are the lost cause because all you can say are meaningless cliches, nothing more than a word salad with no substance to it at all.

The wine glass in resonance has nothing to do with your meaningless statements (unless you change that) about a "Joule Thief in resonance."

Since you are playing the "MileHigh you just don't get it" game, let's see your smarts with respect to the clip. Please Describe the resonance process in simple terms for the wine glass and describe how the resonant frequency is determined for the wine glass in a generic sense. In other words, how and why is the wine glass resonating, and you should not talk about the external speaker at all in your discussion. I am not interested in the external speaker at all, I am just asking you how the wine glass resonates. If you flick your finger at a wine glass it will resonate, what is happening?

So, we will see if your talk about a "resonant Joule Thief" has any substance to it at all, or if it is all just meaningless bluff and useless cliches.

MileHigh

MileHigh · « **Reply #515 on:** February 29, 2016, 06:46:44 PM »

Just because a mechanical device like an ICE or a sewing machine has all sorts of adjustments that are related to the cycle timing, it does not necessarily mean that said device "resonates."

Look, an ICE runs over a wide range of speeds does it not? Meanwhile resonance happens at a single frequency. When a sewing machine is sewing a seam is it resonating or is it simply sewing stitches at a certain operating frequency? Note the sewing machine runs at variable speeds also.

The whole idea is simply wrong.

Lidmotor · « **Reply #516 on:** February 29, 2016, 07:58:49 PM »

Quote from: tinman on February 29, 2016, 01:52:48 PM

Well if it is the cap that is some how self charging at this rate,then we had better look further into it,as the circuit has been cycling for two days now,without any meters or the scope hooked up to it-->to eliminate any chance that either may have been charging the cap. But as the cap dose not charge up with the circuit disconnected,then it's a sure thing it is not the cap that is self charging.

I connected a 10 meter length of wire as an antenna,and it made no difference at all to the charging rate???.

Brad

Brad:
This is really good news. My tests with super capacitors are similar to what you said about them not rebounding after being shorted for a long period of time. They do bounce back some but not near enough to drive a circuit. You are getting energy into that thing from somewhere. After you disconnected all the test gear then the only way the energy can be getting into the system is through the air. That is ambient energy coming from somewhere. If you gather up the experiment and put it in your backyard and it doesn't recharge that is still OK by me. Something in that room then is recharging the circuit. I hope that you have a good handle on exactly how your setup is configured so that perhaps it can be replicated.

---Rusty

MileHigh · « **Reply #517 on:** February 29, 2016, 10:22:06 PM »

Quote from: webby1 on February 29, 2016, 07:01:36 PM

It does not mean it MUST,, but there are resonances that an ICE uses to its advantage,, maybe you could look up volumetric efficiency and how to improve it.

Your statement and comparison to a sewing machine indicates you do not have a lot of experience with ICE's,, I do.

Most people do not even know that the stroke is not symmetrical,, nor that in high performance engines the crank to wrist can have an offset angle and that the charges have mass and pressure that creates a resonance, this is where the peak power is made,, the length of the rod is also chosen carefully.

The parts may not when viewed as independent parts,, even if they are balanced to use the motions,, but the system as a whole does,, or can.

P.S. the next time you use a sewing machine why don't you play with the bobbin and or spool tension

I did not compare an ICE to a sewing machine, you are making an inference that isn't there. It makes no sense to then say that it indicates I don't have a lot of experience with ICEs. Nonetheless the fact is you are right, I only have a lay person's knowledge of ICEs and I don't service or repair or maintain then. It's all moot because we are not talking about ICEs except to state that they have nothing to do with resonance.

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nor that in high performance engines the crank to wrist can have an offset angle and that the charges have mass and pressure that creates a resonance

What's resonating? If you can't answer it, then what?

For sure you can tune hundreds of parameters for an ICE including the engine computer ROM, but it's not resonance. Resonance really means something, it's not a word that you can just throw around. The same thing applies to the simple Joule Thief. The backdrop to all of this is this has been going on for years on the forums, the blind belief that all sorts of different circuits will be "more efficient" if they "resonate." The problem is that people don't define what "efficiency" means and they don't define "resonance." Ultimately it's a form of willful ignorance and fantasy talk. That's what's happening with Brad right now. He is taking it all as a given, and it's just the same old thing with the revolving door of resonance, and goes right back to an Einstein quote that I recently posted.

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intake runners and scavenge waves and all sorts of things are "tuned".

Is there anything to do with resonance in that statement? If so, what is resonating and how is it resonating?

I think part of the problem is that people simply ignore what resonance is and really means, or, they don't even know what it really is and what it really means. I have already gone over that many times so I won't discuss it again. Let's see if Brad can put any substance behind his meaningless resonance buzz word talk.

Ultimately this is a simple exercise in finding the truth and learning to stop deceiving yourselves.

MileHigh

Magluvin · « **Reply #518 on:** February 29, 2016, 11:40:10 PM »

Webby is correct about ICEs. Some Ferrari( and possibly other high end cars) engines have actuators on sliding intake ports that change the length of the tubes to adjust to the rpm/freq of the engine.
Longer tubes provide better low end and shorter tubes provide better upper end. It is called tuning. Like a radio in a sense. Tuning for a proper freq.

Mags

tinman · « **Reply #519 on:** March 01, 2016, 12:41:40 AM »

Quote from: webby1 on February 29, 2016, 07:01:36 PM

It does not mean it MUST,, but there are resonances that an ICE uses to its advantage,, maybe you could look up volumetric efficiency and how to improve it.

Your statement and comparison to a sewing machine indicates you do not have a lot of experience with ICE's,, I do.

Most people do not even know that the stroke is not symmetrical,, nor that in high performance engines the crank to wrist can have an offset angle and that the charges have mass and pressure that creates a resonance, this is where the peak power is made,, the length of the rod is also chosen carefully.

The parts may not when viewed as independent parts,, even if they are balanced to use the motions,, but the system as a whole does,, or can.

P.S. the next time you use a sewing machine why don't you play with the bobbin and or spool tension

I would not think that MH could even grasp the fact that ICEs !do! operate best at resonant frequencies. If you ask him the reason for the large double cone shaped expansion chamber on a high performance two stroke engine,and what that has to do with the power band of the engine,he would be lost. He would not be able to explain as to how that !resonant! relationship between the expansion chamber of the exhaust and the engine actually sucks the exhaust gasses out of the cylinder at the right time,insuring that the cylinder is evacuated of all burnt fuels and gasses,and at the same time,draws in the next charge of fuel/air mix from the crankcase--there is a reason it is called the loop charge system.

The two stroke ICE and the JT are so much the same it's not funny,but MH cannot connect the dot's.
The timing on both is critical,where the source of energy has to be introduced into the system at a very precise time-with the ICE,that is the time you ignite the fuel,and with a JT,that is the time you switch on the transistor. In both cases,the desired outcome is to obtain maximum conversion of that energy source into a power output. If you get the timing wrong on either,then more of that energy source is converted into waste heat.

There is so many resonant factors in a two stroke engine that can increase it's performance, it's not funny. The fact that MH seems to think there is only one resonant frequency, just go's to show how little he knows. Even an inductor has multiple resonant frequencies--something i thought he would know.

Brad

MileHigh · « **Reply #520 on:** March 01, 2016, 01:32:43 AM »

Brad:

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I would not think that MH could even grasp the fact that ICEs !do! operate best at resonant frequencies.

Well that's extremely curious considering that ICEs operate through a whole range of frequencies. Just that fact renders your discussion moot.

Let's not get into a pants peeing contest. We are talking about electrical resonance. When you talk about a two-stroke engine you are talking about matching chamber sizes and proper timing and stuff along those lines. One more time, that is more akin to how a conventional Joule Thief operates as a switching device that does not have a resonant frequency, it has an operating frequency.

I will repeat, we are talking about electrical resonance, and there is indeed a 100% equivalent to that in the form of mechanical resonance, and that mechanical resonance has nothing whatsoever to do with an engine moving gasses around - nothing.

Do you get that? There is true mechanical resonance and it has nothing whatsoever to do with tuning a gas engine and the operating parameters of an engine. Nor are you going to change the definition of resonance to suit your fancy. There will be no bait and switch when it comes to resonance.

So I discussed a whole slew of issues related to the alleged resonance in a Joule Thief and I look forward to reading your responses.

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Even an inductor has multiple resonant frequencies--something i thought he would know.

Stop peeing your pants and I look forward to your responses.

MileHigh

tinman · « **Reply #521 on:** March 01, 2016, 02:30:57 AM »

Quote from: MileHigh on February 29, 2016, 10:22:06 PM

.

Ultimately this is a simple exercise in finding the truth and learning to stop deceiving yourselves.

MileHigh

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It's all moot because we are not talking about ICEs except to state that they have nothing to do with resonance.

Absolute rubbish.

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What's resonating? If you can't answer it, then what?

Go do some research on how the expansion chamber on the exhaust of a high performance two stroke ICE is designed to work,and how it increases the efficiency of said engine.
That is one example of an existing resonant factor in an ICE-there are many others.

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Resonance really means something, it's not a word that you can just throw around. The same thing applies to the simple Joule Thief.

Thats correct.
Resonance is two components of a system that work in harmony.
With a JT,those two components would be between the induced current into the inductor,and the rise and fall time of the magnetic field. When the timing and duration of the induced current is in harmony with the rise and fall time of the magnetic field,then you have resonance.Current is the man pushing the child on the swing,and the child is the rising and falling magnetic field.
And like i said before,there is no point trying to push the child in a forward direction,when he is only half way through the back swing. You would simply be wasting energy -also in the form of heat.

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The backdrop to all of this is this has been going on for years on the forums, the blind belief that all sorts of different circuits will be "more efficient" if they "resonate." The problem is that people don't define what "efficiency" means and they don't define "resonance." Ultimately it's a form of willful ignorance and fantasy talk. That's what's happening with Brad right now. He is taking it all as a given, and it's just the same old thing with the revolving door of resonance, and goes right back to an Einstein quote that I recently posted.

More rubbish.
Many times it has been said that efficiency (in the case of the JT) would be the maximum conversion of electrical power,where we take a low voltage,high current,and convert that into a higher voltage,lower !overall! current that we can use to drive our LED. Resonance increases the efficiency of this conversion,as it reduces the overall waste heat,due to the system components working in harmony--as explained above. Like the ICE,if you get the timing right,then the system will work in harmony(resonance).
The only thing happening to me right now MH,is me wasting my time trying to explain as to how resonance can increase efficiency's in many different type's of systems. This is something you should already know,being the almighty you claim to be.

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I think part of the problem is that people simply ignore what resonance is and really means, or, they don't even know what it really is and what it really means. I have already gone over that many times so I won't discuss it again. Let's see if Brad can put any substance behind his meaningless resonance buzz word talk

I think that it is you that dose not know the complete meaning of resonance MH.
The fact that you believe that operational timings between various parts of an ICE has nothing to do with resonance is proof of that.

I will give you one very clear example of two components of an ICE engine working in harmony(resonance),and the how and why this resonant relationship increases both the power and efficiency of that ICE. For this example,we will use the two stroke engine,and it's resonant relationship with the exhaust expansion chamber. The expansion chamber is shaped like two funnels that are joined together at the two larger ends,so as you have a small inlet opening,and a small outlet opening.

The fuel air mix has just be ignited,and the piston is forced down.
The piston starts to pass the exhaust port,and gas begins to flow out into the expansion chamber.
Due to the shape of the expansion chamber,a vacuum is produced at the exhaust port.
This vacuum not only draws all the expended fuel/air mix out of the cylinder,but also draws in a portion of the new fuel/air mix from the crankcase,via way of the transfer port's.
At the precise time the piston has reached BDC,the gas that is flowing through the expansion chamber is starting to be compressed,due to the shape of the rear wall of the expansion chamber.
At the very same time the piston starts it's return to TDC,the portion of the new charge of air/fuel mix that was stored in the inlet portion of the expansion chamber,is pushed back into the cylinder due to the pressure that now exist in the expansion chamber.
At a given RPM,this action between the pistons position,and the back and forth motion of the gas flow in the expansion chamber reach a point of resonance(harmony)-->this is the point the engine reaches !what is know as! it's power band--point of resonance between piston motion,and the flow motion of the gases.
The increase in efficiency is due to the fact that in stead of that portion of new charge simply flowing out of the exhaust (as it did with earlier two strokes),it is now stored in the expansion chamber,and forced back into the cylinder due to the pressure build up in the expansion chamber itself. This also increases the pressure in the cylinder(much like a turbo dose),and thus resulting in a more powerful explosion on the next power part of the cycle.

So now tell me that an ICE has no resonant operations taking place that increase not only the power,but also the efficiency.

If you want to take me on in this subject,be my guest.
At the age of 17,i modified a 500cc single cylinder,naturally aspirated,carbureted engine that developed 72rwhp based around these principles. In those day's,that was a lot of HP for a bike that weighed only 220lb.

Resonance= operational harmony between system components.

Brad

tinman · « **Reply #522 on:** March 01, 2016, 02:46:51 AM »

author=MileHigh link=topic=8341.msg475934#msg475934 date=1456792363]
Brad:

MileHigh

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Well that's extremely curious considering that ICEs operate through a whole range of frequencies. Just that fact renders your discussion moot.

Let's not get into a pants peeing contest. We are talking about electrical resonance. When you talk about a two-stroke engine you are talking about matching chamber sizes and proper timing and stuff along those lines. One more time, that is more akin to how a conventional Joule Thief operates as a switching device that does not have a resonant frequency, it has an operating frequency.

I will repeat, we are talking about electrical resonance, and there is indeed a 100% equivalent to that in the form of mechanical resonance, and that mechanical resonance has nothing whatsoever to do with an engine moving gasses around - nothing.

Do you get that? There is true mechanical resonance and it has nothing whatsoever to do with tuning a gas engine and the operating parameters of an engine. Nor are you going to change the definition of resonance to suit your fancy. There will be no bait and switch when it comes to resonance.

More complete bullshit--as i explained in my last post.
You clearly have no idea about obtaining maximum efficiency's from ICEs,or where resonating factors come into play.
Your out of your league on this one MH,as i have been building and tuning engines since i was 13 years old. I was taught by the best of the best,and i am qualified in this area.

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[/b]So I discussed a whole slew of issues related to the alleged resonance in a Joule Thief and I look forward to reading your responses.

I have given my response in my last post.

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Stop peeing your pants and I look forward to your responses.

The only one peeing there pant's MH,is you-now that i have !once again! put you and your rubbish back in your box.

Brad

Magluvin · « **Reply #523 on:** March 01, 2016, 02:49:21 AM »

If you have ever ridden a dirt bike with a 2 stroke engine, there is an area in the rpm range we used to call the power band. And when you experience it for the first time, it can scare the boogers out of you.. This area of the rpm range is very powerful and for reasons brad speaks of. Changing the exhaust pipes/muffler, intake changes effect where this power band is in the rpm range. Usually the factory has it right, but you can tweak for more. It usually happens in the upper rpm, so it builds on you in each gear. It is where the engine has everything going for it as in, the intake and the exhaust are tuned for that particular audio freq and intake and exhaust have enhanced ability to give the engine more in and easy out and not have to work really hard to get it, as in creating suction for intake and having to push out high pressures of combustion. So the engine has more power out due to very little losses from the intake/out take cycles. Plus a 2 cycle is a full cycle per revolution, and a 4 cycle is a single cycle per every 2 revolutions. So the 2 cycle can produce more of a pure wave rather than a reduced duty cycle of a 4 stroke.
2 strokes are amazing machines and very simplistic with the least amount of moving parts.

Mags

tinman · « **Reply #524 on:** March 01, 2016, 03:16:58 AM »

Some examples of resonance in ICE engines

https://en.wikipedia.org/wiki/Helmholtz_resonance
Quote from link : Helmholtz resonance finds application in internal combustion engines

How expansion chambers work
https://en.wikipedia.org/wiki/Expansion_chamber
quote from link : On a two-stroke engine, an expansion chamber or tuned pipe is a tuned exhaust system used to enhance its power output by improving its volumetric efficiency.
Two stroke engines using tuned exhausts produced far more power than if running with a normal silencer.
The high pressure gas exiting the cylinder initially flows in the form of a "wavefront" as all disturbances in fluids do. The exhaust gas pushes its way into the pipe which is already occupied by gas from previous cycles, pushing that gas ahead and causing a wave front. Once the gas flow stops, the wave continues, passing the energy to the next gas down stream and so on to the end of the pipe. If this wave encounters any change in cross section or temperature it will reflect a portion of its strength in the opposite direction to its travel. For example, a strong acoustic wave encountering an increase in area will reflect a weaker acoustic wave in the opposite direction. A strong acoustic wave encountering a decrease in area will reflect a strong acoustic wave in the opposite direction. The basic principle is described in wave dynamics. An expansion chamber makes use of this phenomenon by varying its diameter (cross section) and length to cause these reflections to arrive back at the cylinder at the desired time in the cycle.<-- the resonant frequency factor.

https://en.wikipedia.org/wiki/Volumetric_efficiency

Quote from link ; Many high performance cars use carefully arranged air intakes and tuned exhaust systems that use pressure waves to push air into and out of the cylinders, making use of the resonance of the system. Two-stroke engines are very sensitive to this concept and can use expansion chambers that return the escaping air-fuel mixture back to the cylinder. A more modern technique for 4 stroke engines, variable valve timing, attempts to address changes in volumetric efficiency with changes in speed of the engine: at higher speeds the engine needs the valves open for a greater percentage of the cycle time to move the charge in and out of the engine.

Volumetric efficiencies above 100% can be reached by using forced induction such as supercharging or turbocharging. With proper tuning, volumetric efficiencies above 100% can also be reached by naturally aspirated engines. The limit for naturally aspirated engines is about 100%;[1] these engines are typically of a DOHC layout with four valves per cylinder. This process is called Inertial Supercharging and uses the resonance of the intake manifold and the mass of the air to achieve pressures greater than atmospheric at the intake valve. With proper tuning (and dependent on the need for sound level control), VE's of up to 130% have been reported in various experimental studies.[2]

I highlighted the resonant part MH-so as you dont miss it.
So now we already have two resonant factors being utilized in an ICE--the exaust resonant system,and the intake manifold resonant system.

But let me guess--they all have it wrong,and there are no resonant factors being utilized in ICE's to increase efficiency and performance

Should i go on MH,and post another 100 links explaining resonant systems in ICE's ?.

Brad

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