Joule Thief 101

[MileHigh]

Brad:

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.

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]

.

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

MileHigh

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

Absolute rubbish.

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.

 

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.

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.

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]

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





MileHigh

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.

[/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.

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]

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]

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