Watts do not matter. Its all about wire temp. Read on

[pdib]

Anyway, catching up (still sorry). Thicker wire is a larger mass. As long as your battery is capable of dumping sufficient amps to heat that thicker mass as much as thinner wire, your making more hot mass. Add more juice, and you get more vapor. The vapor is thicker because it is in a confined space (atty, your mouth, your lungs). More vapor bits hit more nerve endings = more flavor.


You can overpower your wikicoil with a car battery.

You can underpower your battery with Lake Geneva.

 

[dr g]

Yep, that is what you said. Your plateau is a transfer of energy from coil heating to phase change. Plateau as long as you can supply the matter to transform.

Yes. So between a thin and thick coil wire, under operational conditions, the coil temperature would likely be within a similar range. The energy transferring from the coil to liquid, however, would be quite different.

 

[jasl90]

Heat energy is not always manifest as a change in temperature. I didn't say more heat energy was not generated, I said the temperature would not necessarily change.

Lol... Yes it will. Adding heat energy will alway manifest in a change in temperature. It's heat... If it didn't change the temperature, it wouldn't be heat.

 

[pdib]

It's energy that is either going to heat or directly (so rapidly that we may as well call it "directly") to phase shifting. (?) hmmmmmm?

 

[pdib]

Meaning, maybe we shouldn't look at it as "creating heat, and THEN making steam"


rather, creating heat OR making steam

 

[dr g]

Lol... Yes it will. Adding heat energy will alway manifest in a change in temperature. It's heat... If it didn't change the temperature, it wouldn't be heat.

Heat and Temperature- Concepts

 

[pdib]

so, then, its not about wire temp. Its about how much energy (heat . . . .atomic jiggle) can you transfer from the battery, and at what rate, directly to the juice atoms. Its not about wire temp, or juice temp. Its about quantity and speed of atom jiggle transfer. Which totally comes back to mass and contact area and supply.


so. what's the question?

 

[jasl90]

From your source...

when you add energy to a bunch of atoms they move faster and get hotter

 

[dr g]

From your source...

Please don't be thick. The entire article is about the difference between heat and temperature. Credit to Mad Scientist for bending my own thinking a little bit by reminding me of the physics of phase change.

Wire temperature as a concept is useful for understanding the relationship between current, wire size, and heat energy, but the actual function of an atomizer is to change the phase of a liquid, so the temperature per se is not going to reflect the heat energy directly.

so, then, its not about wire temp. Its about how much energy (heat . . . .atomic jiggle) can you transfer from the battery, and at what rate, directly to the juice atoms. Its not about wire temp, or juice temp. Its about quantity and speed of atom jiggle transfer. Which totally comes back to mass and contact area and supply.


so. what's the question?

The initial point was that while the thread title says it's about wire temp, it's not technically about wire temp since the temperature any coil vapes at is probably similar.

 

[pdib]

nope. yep. 's about mass, surface area and available stored energy.

 

[Mad Scientist]

Here is something I remember doing at about age 10 in science class. It gets the point across. The torch flame is over 3,000 degrees F. The paper will not burn until the water is gone. The temperature of the cup is very close to 212 degrees F.

Boiling water in a paper cup - YouTube

 

[BJ43]

I still see it as temperature. Sure all coils vaping correctly to change the phase are all at approximately the same temp. The main reason for this thread is that when VW came out it was advertised that you just set the watts and all coils you put on would vape the same. This is completely false. At similar wattage the measured temperature of 32g 2ohm coil is much hotter than a 28g 2ohm coil. The watts are spread out over a much larger surface area on the 28g. You can complicate it all you want but on a theoretical point the juice doesn't care if it is 28g, 32g, round or flat, at that point it is temperature at that theoretical point that changes the phase. So on a 28 g 2ohm that theoretical point would be cooler in the previous example and would not give the same vapor. So in relation to What was being advertised for VW units the thread is accurate " wattage does not matter".

 

[jasl90]

Well now, that is interesting... I remember doing that very same experiment as a wee lad myself...

As long as the flame doesn't get hot enough to outpace gravity's ability to pull water into the pockets formed by the steam, the cup won't burn.
Turn the flame up, the water boils faster. Turn the flame down, it boils slower.

Let it never be said that I won't be swayed by compelling evidence.
I definitely see how that would directly translate to the topic at hand. As long as the wick has the ability keep the coil wet its actual surface will in fact NOT exceed a certain temperature... Damn you! I concede... Well done sir!

That said, the water in the cup is not limiting the amount of heat/energy entering the system. Increase the heat of the flame, the water boils faster and more steam is generated. Decrease the heat of the flame and the opposite occurs... So, there is still a direct correlation between the heat of the flame and the boil rate of the water.

The same will hold true in an atomizer. We can still directly correlate the the temperature and response time that we observe when dry burning a coil to the vapor produced when saturated w e-juice. The fact that surface temp of the coil is being limited, doesn't mean that the heat it's imparting into the system is being limited.

Should you agree with the above?

 

[Mad Scientist]

Yes, the idea is to get the most juice to boil without burning. That requires good heat transfer to a lot of juice that replenishes itself by wicking. The idea at this point is really just to start thinking about ways to evaluate an atomizer design / build. Just trying it is kind of subjective and what seems better one day isn't the next day. When I get the time I plan to wrap a thermocouple in with the wick. First experiment will be a power versus temp curve. Should be interesting just to see what we can see.

 

[pdib]

So, the thicker the wire, the greater the mass that is heated. This lends itself to more surface area (btw the juice coats the coil, outside too . . see pic). Then its a question of providing sufficient energy to a short enough length of wire to build heat induced resistance rapidly. After that, its a question of supplying sufficient juice to allow for a reaction to endure 10 seconds (lung capacity, mouth draw capacity). After that . . . . its about not spoiling juice (by cooking it) which won't be consumed during the current phase change session. Lastly, heat energy should not be wasted (dissipated) by being transferred to the atomizer, or the wicking medium unduly.


BTW
Here's where I'm not a scientist/theoretician. I'll be crass enough to hop right over to anecdotal experience. After months of seeking the perfect vape (actively, creatively, experimentally), the place where I found this magic mix of factors . . . . . . . is 26g Nichrome @ .5-.7Ω (goes to mass/length/surface area), in a micro coil (conserve heat and exacerbate resistance, increase inductance), with sterile cotton wick (very low heatsink/footprint, holding lots of juice), in the RM2 (ceramic base, air-coolinig fins, squonkable), on the REO (bottom feeder, only cook the juice your phase shifting, leave the rest pure), with a 24 amp discharge battery.


Juice on outside:




26g/25g coil:





RM2 cap/cooling fins on REO Grand

 

[jasl90]

Pdib... You get a new REO?

 

[pdib]

#1 is now in wife's posession. #4 is arriving tomorrow.










(they are . . . . addictive . . . to say the least . . . . . they make you happy)

 

[jasl90]

Lol... I'm familiar with the sickness. 2 ProVari's and 8 high end mechs.

 

[dr g]

I still see it as temperature. Sure all coils vaping correctly to change the phase are all at approximately the same temp. The main reason for this thread is that when VW came out it was advertised that you just set the watts and all coils you put on would vape the same. This is completely false. At similar wattage the measured temperature of 32g 2ohm coil is much hotter than a 28g 2ohm coil. The watts are spread out over a much larger surface area on the 28g. You can complicate it all you want but on a theoretical point the juice doesn't care if it is 28g, 32g, round or flat, at that point it is temperature at that theoretical point that changes the phase. So on a 28 g 2ohm that theoretical point would be cooler in the previous example and would not give the same vapor. So in relation to What was being advertised for VW units the thread is accurate " wattage does not matter".

I just noticed that this post had gone unaddressed. I believe in the situation you describe we have to start looking at the heat energy gradient of the coil along its length. At the point of vaporization, the temperature would indeed still be the same as in all other examples, but that "area of vaporization" would be smaller in an underpowered coil. You could mitigate this if you had enough power to "soak" the coil with repeated firings or an extended firing.

So it actually still is not about temperature in the area where the atomizer is functioning properly. But it is still true that, as far as the example, watts are not a reliable means of comparison between different coil setups.

I do believe, however, that watts are a reliable means of knowing the potential of different coil setups. In my experience, with an optimized build, you can achieve similar things with coils built in different ways, at the same wattage.

 

[BJ43]

I just noticed that this post had gone unaddressed. I believe in the situation you describe we have to start looking at the heat energy gradient of the coil along its length. At the point of vaporization, the temperature would indeed still be the same as in all other examples, but that "area of vaporization" would be smaller in an underpowered coil. You could mitigate this if you had enough power to "soak" the coil with repeated firings or an extended firing.

So it actually still is not about temperature in the area where the atomizer is functioning properly. But it is still true that, as far as the example, watts are not a reliable means of comparison between different coil setups.

I do believe, however, that watts are a reliable means of knowing the potential of different coil setups. In my experience, with an optimized build, you can achieve similar things with coils built in different ways, at the same wattage.

Interesting point, but if I make a 2ohm coil the size of a stove burner and put 15 watts thru it, I can hold it in my hand it it will not even get warm.