What Happens to Flames in Higher Air Pressure?

Have you ever wondered how flames react when the air pressure around them increases? In this eye-opening experiment, we place a candle inside a pressure chamber and gradually raise the air pressure to see what happens to the flame. Will it burn brighter, flicker out, or behave unpredictably? Join us as we delve into the science of combustion and air pressure, observing the surprising effects on the flame's size, shape, and intensity. This fascinating demonstration not only reveals the behavior of fire under different atmospheric conditions but also provides insights into real-world applications. Don't miss this captivating exploration of flames in higher air pressure!
Our second channel / @beyondthepress
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Do not try this at home!! or at any where else!!
Music Thor's Hammer-Ethan Meixell

[@HydraulicPressChannel]

Let me know what else we should try with the chamber! I can any liquid or gas there and pressure goes up to 300 bars

[@felixar90]

Marshmallows

[@roadwarrior6555]

Not sure if you can pull a vacuum. Water is supposed to boil at .01 bar at room temperature. Or maybe increase pressure until liquid nitrogen stops boiling? Different material phase changes are interesting...like liquid to solid and back again.

[@FrietjeOorlog]

@@roadwarrior6555 If you pull a vacuum it also stops boiling because it'll freeze.

[@felixar90]

@@roadwarrior6555 no need to increase the pressure, it’ll go up by itself after you enclose the liquid nitrogen. It’ll never stop boiling with only 300 bars tho. In fact I don’t think you can keep it liquid at room temperature with any amount of pressure. It’ll go supercritical at some point. But even around 16°C you need a 450 bars chamber.

[@09mxrider]

It's your compression ratio for the fuel your burning at 3 bar it's the optimal environment for combustion of that given fuel further more different fuels would inherently have their optimal burn atmosphere

[@davidjernigan8161]

Maybe try the same experiment with an alcohol burner. There might be less smoke and mist.

[@KnifeKnut]

Even better, you could try igniting the exhaust valve emission.

[@PaulG.x]

It will be better but alcohol is a carbon compound and as oxygen is depleted it will also produce unburnt carbon

[@isaacthedestroyerofstuped7676]

Perhaps premixing the oxygen an fuel would help? It'd be more dangerous, but it would nearly eliminate the issue of the reactants being unbalanced.

[@MartysRandomStuff]

@@isaacthedestroyerofstuped7676 It could be very dangerous to use higher percentage of oxygen, causing the candle to burn out of control and burn through the o-rings on the chamber. The chamber is probably rated to deal with any pressure spikes that might happen but doesn't look like it's designed to shield the O-rings from fire. Chambers made for bomb calorimetry are machined so gasses burning in the chamber don't have a straight path to the O-rings, even then sometimes the O-rings catch fire and the pressure gets released unexpectedly.

[@lajoswinkler]

The chamber is way too small to ensure linear increase in partial pressure of oxygen with increasing total pressure because candle is consuming oxygen too fast. Basically, you're getting high pressure air with less oxygen. Brighter and more sooty is the result. Soot makes incandescence. Experiment would have to be repeated in a large chamber where one of the reactants does not have an appreciable impact on the concentration of other reactant.

[@EggBastion]

Augh curses, that sounds like a bind.

[@ExperimentLife]

You could just make the flame smaller.

[@108gk]

Dalton's law at work like a snake eating it's tail.

[@VcSaJen]

Can't you fix it with filling the chamber while simultaneously releasing the air? It would be windy, but there will be fresh oxygen

[@ScoobiKubi]

​@@VcSaJenexactly, thats what we do in diving

[@WoodworkerDon]

HPC is ALWAYS much more interesting than "one Google search away." 👍5,000,000

[@TheOneWhoHasABadName]

And now, HPC is one google search away (for this question at least) HPC makes google searches more interesting

[@cyfralcoot65]

Instead of the complex procedure of closing the chamber with the valve being open while some oxygen is burning away, you can try to ignite the candle inside the chamber using a blue laser

[@chitlitlah]

It's affected mostly by the partial pressure of oxygen. Air is about 22% oxygen, so with 1 atm of air, you have 0.22 atm of oxygen. With pure oxygen at atmospheric pressure, you have of course 1 atm of oxygen. If you put in air at 10 atm, you have 2.2 atm of oxygen.

[@lajoswinkler]

Unless the chamber is so small the candle is changing it rapidly, which is what's happening here.

[@horrido666]

Same concept as a supercharger on an engine.

[@Sparky_D]

Yeah, it started choking itself out because there wasn't enough space to dissipate the smoke

[@CyanOgilvie]

I think that's half of it, but there are two competing effects: as the partial pressure of the oxygen goes up (increasing the reaction rate), the partial pressure of the nitrogen also goes up, which is taking heat away from the reaction, at a certain point it looks like that effect is dominating over the increased reaction rate from the O2

[@MikkoRantalainen]

@@CyanOgilvie I would also guess that heat cannot push the smoke effectively away from the flame which causes smoke to remain close to fire and cause worse burn. After all, the heat is moving air against gravity and with higher pressure the air above the flame is going to weight 5-10 times more than usual so it's harder to move.

[@d4rk0v3]

I love so much that you can see the interference from the smoke in the data on the lumen graph.

[@Lilith-Rose]

I still would really like to see you use bob the bot with a cheap angle grinder to cut a really strong spring under pressure and similar things under pressure in the press to simulate workplace accidents, perhaps even a high pressure gas cylinder that is mounted really securely. Lots of things you can do with your fancy robot and bunker that are really stupid and dangerous but would make good safety videos

[@adrielburned6924]

I second your idea

[@adrielburned6924]

I third your idea. 😊

[@108gk]

Breaking a scuba tank under air pressure would destroy the bomb proof enclosure. A smaller air tank at 1 atm inside the pressure chamber full of water to collapse the tank would be interesting. Something made with carbon fiber might be worth trying as well.

[@Lilith-Rose]

@@108gk oh absolutely a scuba tank would be a terrible idea, I was thinking more along the lines of a domestic 6kg gas bottle that has been water flushed and pressurised using nitrogen or regular air

[@PrincipalAudio]

You could try different fuels to see if they burn differently. Candles using petrol and diesel as fuel might be interesting, since these are used in vehicles which are either naturally aspirated or supercharged. Would be interesting to see if pressure changes the way they burn. In terms of the speaker, the "formant" is changed, not the pitch. The pitch is the same but the resonant peaks inside the chamber are shifted in frequency so it accentuates different parts of the audio, almost like adding EQ in different places.

[@dougaltolan3017]

👍 EQ from short reverb (delay). A simple one would be a comb filter. Changing the pressure changes the reverb (delay) time, changing the filter.

[@justinahole336]

It's all about the partial pressure! You also have water being added to the system and when the pressure dropped, the water condensed to give the haze. Lots of fun!

[@wampaphatt9154]

Have you guys tested a little bit of mercury in your pressure chamber? Typing in mercury under pressure, all I get is the hit Freddie Mercury song Under Pressure featuring David Bowie

[@superpaul79]

😂 👏👏👏

[@dougaltolan3017]

👍🤦‍♀️

[@Donitsikoira]

😂

[@takanara7]

It won't do anything interesting. Mercury is used in manometers because it's so stable in volume relative to pressure changes.

[@wampaphatt9154]

@@takanara7 thank you for this interesting fact

[@joelclifton6312]

While the percentage of oxygen stays the same, the amount of oxygen increases, allowing faster and more efficient combustion, creating a hotter and brighter flame. But only to a point, and then it levels off even with increased pressure.

[@ehsnils]

And the longer it's burning the more carbon dioxide and water vapor you'll get, which impacts the result.

[@Mart77]

Same thing happens with internal combustion engines when turbocharger is added. As there is more air molecules for every cm3 of air, the burning gets faster. In engines to combat that the ignition timing has to be adjusted to ignite the fuel a bit later than in naturally aspirated application.

[@KnifeKnut]

Interesting, the acoustic coupling of the air to the chamber walls was much better at high pressure, which is why we heard it more clearly.

[@Sparky_D]

Honestly, Hanna's voice is super cute. So cool to have a partner helping you with these crazy experiments

[@dr_jaymz]

Can you imagine her angry? I can't. I'm sure it happens but would be interesting to see if she goes higher or lower pitched?

[@captainxemo3804]

Higher pressure would equal greater oxygen density therefore it burns brighter, and less completely (hence the smoke).

[@lajoswinkler]

Greater oxygen partial pressure would not cause smoke. On the contrary.

[@charmio]

Yeah I don't understand why more oxygen would cause smoke. There's more nitrogen and combustion products as well though, perhaps they're removing the heat needed for combustion before it can occur. I believe that's also why a spoon in a candle flame will create soot, the metal is removing heat from the reaction.

[@polarbearsaysyummy5845]

Towards the end, the histogram looked like the Hogwarts sorting hat.

[@billlane7486]

Would have been fun for one of the candle shots to have just opened the big release at the end. See if it did blow the candle out. The speaker might work better with an old type diaphragm speaker where you can watch the paper cone moving particularly as the high pressure seems to take out the base.

[@AudioOrchardMusic]

The chamber is pretty small for this, but it would be interesting to measure the change in the speed of sound while the pressure increases. Perhaps a high frequency transient played by one synchronized device and measured by another at the other end of the chamber.

[@FrietjeOorlog]

More pressure = more oxygen, even if the ratio of oxygen to nitrogen stays the same. So no wonder it gets brighter. I'm not sure what happens above 3 bar that makes it dimmer again. Maybe the wax can't stay liquid as easily so the wick has a harder time getting fuel or something.

[@Mus.Anonymouse]

It’s not the liquid wax that burns, it’s gaseous wax that burns. Higher pressure prevents (somewhat) the wax to enter gaseous state.

[@pompeymonkey3271]

@@Mus.Anonymouse My guess also. :)

[@jeramiahshastid6041]

As you dive deeper the partial pressure of O2 increases to the point it becomes lethal. That’s why Saturation divers use far less than the 21% O2 found at 1 atmosphere. SEMPER FI

[@sandyleask92]

@@Mus.Anonymouse You are correct. For substances like wax, which are less volatile, than say fuel. This effect is particularly noticeable. Wax requires more energy at higher pressures to undergo the phase transition from liquid to vapor, meaning its boiling point increases as external pressure rises. An easy to understand example is at sea level water boils at 100°C at 1atm. Go to summit of Everest with pressure around 0.34atm water boils at roughly 70°C

[@paradiselost9946]

@@sandyleask92 and theres the capillary effect in the wick that draws the molten wax up... theres a bunch of factors at work here...

[@jenspersson_lund]

Having experienced being in a pressure chamber at 10 bar overpressure, I can say that the voice pitch goes up in approximately the same way as if breathing helium. I'm not sure if that is due to the vocal cords working differently or if it is just the change in the speed of sound.

[@landsgevaer]

Speed of sound changes very weakly (not at all in an ideal gas), so I suspect that would not be noticeable. I bet it is because higher density increases the inertia of the air that the conus of the speaker has to move through/with, while the inertia of the conus itself does not change. Therefore, the acoustic impedance characteristic changes as a function of frequency.

[@steffen7416]

They replace nitrogen with helium in high pressure chambers (look for heliox) that's the main reason for the voice change. Helium is way less soluble in blood so when you reduce pressure there's less blood boiling and more surviving ;) and that is generally preferred by most people.

[@BenAlternate-zf9nr]

I would guess it's not so much the pitch shifting up as it is the higher-frequency tones getting relatively louder.

[@jenspersson_lund]

@@steffen7416 This was pure air in a hospital pressure chamber used to treat diving accidents. The squeaky voices combined with the nitrogen intoxication was very funny when you where in the chamber, but when the second gang giggled in there half an hour later it was missing something 🙂

[@robo1000]

Can you use that thing to show what happens when you over pressure fuel injectors? Always wanted to see what would happen if you didn’t upgrade injectors in a NA engine modified to have a turbo. So much pressure they just stop working. Another great video!

[@ggarber4763]

At first I thought the flame might have dimmed at greater pressure because it had burned brighter and used up most of the oxygen. But then it got brighter again when the pressure was reduced. Now my best guess is the air becomes increasingly viscous at increasing pressure and that makes it harder for wind currents to bring a breath of fresh air to the flame. So at some point viscosity effects overshadow increased oxygen partial pressure effect and the flame starves for oxygen in a sea of oxygen.

[@BryanDraffen]

This seems like a banger idea to me.

[@dronelabs556]

A ready cool idea is to feed various types of gases into the chamber via a small nozzle and with a remote ignition system. And try with a few common mixtures of fuels and oxidizers.

[@squidcaps4308]

Not higher pitch but different frequency response. Less low frequencies at higher pressures. Both clips are at D# and in perfect tune. A lot of people don't really understand that a frequency response that has tons of high frequencies is not higher in pitch, it is mostly just a case of not being versed of what those terms mean. If you sing just one steady note and go from almost closed lips to fully open mouth your frequency response changes but the pitch stays the same. The ratio between the various components that make the sound varies. Even better effect is if you let out an "S" sounds, just "shhhhhh" and go from open to almost closed mouth, you hear a "swiuuuh" kind of sound as high frequencies are filtered out. The lower frequencies stay unaltered, nothing is cycling slower there is just an obstruction in the way that makes the lopass filter sweep up and down.

[@centauria9122]

Put CO2 in it or dry ice inside the pressure chamber. It should turn into a liquid at a certain pressure. The dry ice should need to turn into a gas first.

[@zygmuntthecacaokakistocrat6589]

There's lots of confounding variables with this one, the biggest being that the waste gases produced would tend to affect the burn, their buildup would lead to self-extinguishment when they became too concentrated.

[@Thestorminator89]

You need to be able to remove the exhaust fumes make by the candle, whilst maintaining pressure. it started to get brighter but with the fumes building up, combustion is less efficient, like with a car. remove the combustion fumes and the more brighter the flame "should" be.

[@Travecmo]

You guys are great and very much deserve your success. 👍

[@บัวสีโรเจอร์-ศ9ฝ]

I'm too old to explain about vapor pressures and other super technical stuff. As long as there are explosions or other unexpected stuff, I'm happy.

[@Groovewonder2]

I think it's neat that the flame got skinnier and managed to climb several times higher. I think the higher pressure fought back against the flame wanting to push outward due to the pressure of the combustion reaction so it rose and went upwards, and given it was still fighting pressure as it rose, the tip of the flame became more like a spike.

[@AstraCarta]

This does show that life forms could develop fire on a world with a higher pressure atmosphere... so that's cool.

[@MrJansenenjansen]

Great teamwork! 💪

[@garethevans9789]

Almost 10 MILLION, Damn..!

[@MichaelEhling]

4:23 "Not Slytherin, eh? Mmm. Are you sure?"

[@DUKE_of_RAMBLE]

Ah yes, the HPC Scientific Method: STEP 1: Fuck around. STEP 2: Find out.

[@stephenkeeffe4940]

Always very interesting stuff.

[@ThatOpalGuy]

not sure why, but I was never subbed. Well, that has changed NOW.

[@toweri_li]

Insert the MP3 player in the chamber on dampers, so that the sound does not come out directly via the chamber walls ("runkoääni"), but only as transferred through the air. From what could be heard here, the sound frequency spectrum, not pitch, changed. The higher frequencies were boosted, while low frequencies became attenuated. Perhaps the high pressure air transfers high frequencies better? Note that on Mars, the sound of the Ingenuity helicopter was recorded. At pressure 0.6% of that of Earth's, only low frequencies would travel any significant distance. High frequencies die off in a very short distance. This is consistent with your results.

[@Les__Mack]

You guys rock! Thanks for keeping the masses entertained. You should use compressed oxygen rather than compressed air. No just kidding. I meant pump liquid nitrous in.

[@christianmittasch8972]

Super interesting experiment. 👍

[@johntilson2535]

The only problem is the result of combustion are CO (carbon monoxide) and C02, both of which are inert (non-combustible gases) and will compete and eventually overcome the oxygen in the air pressure mixture, no matter the pressure. Wait long enough and the candle flame will be extinguished. At least that's what I think might happen

[@kma3647]

Explaining the candle experiment with chemistry. Combustion is just oxygen + your hydrocarbon transforming to water and carbon dioxide. The byproduct is the light and heat which is how we experience the energy released by the reaction. When you increase the pressure, you simply increase the frequency with which the reactant molecules interact allowing the reaction to proceed faster. The flame gets brighter. Over time, waste products accumulate in the closed system and those product molecules start to get in the way, so the reaction slows down and the flame gets closer to what we originally saw. When you let out the air, you did decrease the pressure, but at the same time, you vented the waste gases which were quenching the reaction. The net result of the change was that it temporarily sped up again and would slow down again as the pressure returned to 1 atmosphere and waste gases started to accumulate again. Eventually the waste gases would separate the reactant molecules, snuffing out the flame.

[@MartysRandomStuff]

Since candles work by turning the wax into a liquid and then a gas in order to stay burning, those steps would also change at higher pressure, so lots of stuff going on.

[@stevencooper2464]

Maybe you can redesign one of your end covers so that you can have electrical and data lines into the chamber; that way you could put a microphone (or other sensors) in the chamber with what ever experiment you're doing, and record more information.

[@rageagainstthebath]

In higher pressure, I think that sound propagates faster, thus the wavelengths become longer. In other words, from sound's perspective, the pressurized chamber behaves like it was smaller than it was. Before it was pressurized, bass sound was dominant just like in bass tubes in automotive audio systems. With higher pressure, the resonant frequency was higher. The same experiment would be interesting with white noise instead of music. I expect that the dominant pitch would gradually rise with pressure and should be clearly audible. Once you find a way to record sound from within the tube. :)

[@dmdeemer]

As you increase the pressure, the candle burns brighter, but in doing so, it consumes the oxygen faster. If you can make a way to supply a fresh stream of pressurized air and exhaust the combustion products (through a regulator perhaps), then you should be able to get a much brighter flame.

[@DaftyBoi412]

The audio one may not actually be what would really happen to sound, but rather how the pressure rise essentually makes the mic membraine tighter/stiffer (as well as the speaker also) not allowing lower freqency vibrations to be produced as easily or recorded as easily. You would have to isolate the pressure's effect on the speaker AND the mic (or at least have a mic and speaker that you know's performance isn't effected by the pressure it's self) to really hear how the pressure effects sound waves themselves, and really small, light material speakers/mics like the ones in phones/ipods/cameras and normal mics will be effected the most by higher air pressure I would imagine. If that's what this test was meant to test lol (I'm sure it was just for fun, but it's interesting to talk about the results).

[@MotherBiscuitLover]

With the candle, I'd like to see a simple comparison of how long the candle stays lit with the chamber sealed at normal pressure, vs. how long it stays lit at 10 bars. Is it consuming the oxygen faster at high pressure, or does it last longer cause there is more air in the chamber?

[@esalehtismaki]

Higher pressure raises the oxygen partial pressure, which increases reaction speed, but the candle also uses the oxygen in closed space, which lowers the mole ratio of oxygen and therefore the partial pressure and slows the reaction. Also the temperature rises, which increases reaction speed. And finally, evaporation of burning gas depends on the temperature of the liquid parafin, which depends on the heat output of the flame, but with delay. So it depends on the size of chamber, the candle, how fast you add air and how well heat escapes.

[@timwaeyaert8339]

Another great video look forward to more

[@scottjgray83]

Best channel on YT

[@Douglas_Blake_579]

Looking a the historgram ... I saw almost double brightness at full pressure and it rolled off significantly as pressure decreased. Obvious conclusion .... more air ... better fire. For the sound test .... put the speaker in about 2 atmospheres then slowly take it down to a near vacuum ... you will hear the tonality change from shrill to boomy then the volume will fall off to zero in a vacuum. (The rising volume with sound pressure change has been well documented on the ISS where the airlocks start with silence then get louder as they will with air.) Pretty cool F***ing around stuff!

[@phonotical]

Could maybe use a tempreature sensor?

[@PushyPawn]

Need more *pressura* !

[@BakedAndAfraid]

hot accents... hot gadgets. Fire = Fuck Yeah!!

[@virtual2152]

FAFO with Stupid Shit. What's not to like about that?

[@Failsafeman100]

Watching this channel reminds me how I should really move to Finland. Where people listen to you, and let you finish speaking without interruption, and that's perfectly normal. Where strangers will respect 2m personal space even though COVID is long gone. Where silent pauses are tolerated and not awkward. No pretentiousness. It's an introvert's paradise

[@PexiTheBuilder]

We dont like 2m personal space, its akwardly close.

[@Emprivan]

Ok, for one you need to paint the inside with the blackest paint, you got loads of noise from reflection in the hisogram thing. But if you noticed the fire basicly did the same as the sound, in the sound seemed brighter.

[@nielsdaemen]

I want to see 100 bars next. Also you can try first bringing up the pressure and then igniting it with a laser

[@susvortin]

Is the chamber rated for vacuum as well? Would love to see many under-pressure experiments to come...

[@youkofoxy]

Maybe add some wires to the chamber, also: a contact microphone may be a nice addition.

[@mrwpg]

Treble and bass sound waves travel differently due to wavelength, higher pressure means the sound is vibrating more air molecules and the treble is reverberating more because there is more air.

[@offdagrid877]

Are you going to use the new press for your water pressure experiments, would be interesting to see what depth you could achieve

[@donaldevans5752]

interesting video .

[@LFTRnow]

I want to see more fire experiments (like the alcohol burner idea) but with much higher pressures. Think you can do 50 or 100 bar in that thing? What happens to fire at THOSE pressures?

[@MartysRandomStuff]

I know sound propagates differently at different pressure, so you would expect the sound to change, but I wonder if the lack of bass is also due to the higher pressure air being harder to move so the speaker itself didn't have enough power to create bass.

[@vaalrus]

Now I have questions about the transitions from solid to liquid to vapour of the candle material at pressure.

[@veryberrykeri]

i think the increase in temp caused by the higher oxygen levels may be causing the wick to burn when it isn't supposed to, aka it is too hot. the dirty combustion of the wick, along with the fast increase in CO2, may be responsible for the mist. a candle is a feedback loop of flame melting solid fuel so it can enter the wick, the liquid fuel sucking through the fibrous wick, the liquid fuel combusting, and heating more solid fuel. eventually the solid fuel will have melted away enough that the flame at the tip of the wick can no longer melt solid fuel at the required rate, so as the flame moves down the wick, the wick curls out of the flame and is consumed. this dance is dependent on melting and combustion temperature--too hot a flame and you may not prioritize the fuel over the wick. soot comes from incomplete combustion, which in the case of candles, is mostly (if not entirely) from the wick. this leads me to believe the excess oxygen is causing early combustion of the wick, and alongside the rapid increase of CO2 from combustion product, is creating an imbalanced and sooty but still high pressure atmosphere that appears misty.

[@KnifeKnut]

A small helium filled balloon might make a good pressure chamber experiment, also try other gasses / mixtures. That gives me an idea for a good send off when the chamber is worn out! Explode a stochiometric oxyacetylene mixture filled balloon in it while it is at maximum pressure!

[@lixulan]

wow that was cool

[@jasone3166]

I'm pretty sure the increased presure would reduce the vapour pressure of the wax which would also compete with the increased oxygen available, along with the oxygen being consumed by the candle. So it;s not surprising that the candle reached a peak around 3 bar.

[@christianfritz6333]

You killed the sorting hat.....

[@phonotical]

Pressure on both sides of speaker cone would be queal so volume/pitch,should remain the same, might have better coupling to the cylinder though, used to do the same thing with a washing machine to see if it is air tight

[@madscientist602]

i liked this

[@C_F_M]

I missed your old theme song!! :D

[@Welgeldiguniekalias]

Sure we learned something. Candlelight comes mostly from glowing soot, right? With the increased availability of oxygen due to the increased air pressure, combustion is more complete, so there is less soot, meaning the flame does not get much brighter even though it gets bigger.

[@BrianLyod-nj1vg]

VILLAN! God dand spell check!

[@KONAmustang50]

We learned that it burns 'dirtier' when the pressure increases. Very sooty.

[@lachlanhatcher9108]

Try adding a spark igniter so that you can light the candle at high pressure. When it's burning from the start, you're oxygen percentage is only going down

[@duncanwallace7760]

I'm guessing the bass sounds require more air to move, so the speaker probably struggles to move that amount of air in high pressure, so you get more of the higher pitched sounds.

[@pauldrice1996]

I'd be interested to see what happens if you were to be slowly letting air out through a pinhole as you increase the pressure so the CO2 and water produced by combustion have a place to go so the air stays closer to the same ratio of gasses.

[@BriankSmith181]

Well the sound one makes sense sound travels forever in water i.e. the ocean bloop.

[@ДжонПартлов]

I think that as the pressure increases so does the partial pressure of oxygen. Therefore, the flames should burn brighter until it consumes all the oxygen in there given that you started the test with a certain amount of oxygen, and it’s burning it as you’re going, really can’t have the same conditions at the beginning of as the end of the test as to how much oxygen content would actually be in the area at that time if that makes any sense.

[@koriw1701]

I must admit that I love coming to Professor Laurie's classes. He and his illustrious associate Hanna (who's buffed out quite nicely) have been teaching me more than I *ever* got out of the American public school system. I even got to hear a bit of death metal that I've never encountered before! Hey professor! What band is that? I want to look them up on my music streaming app.

[@benzonet]

Thors Hammer by Ethan Meixsell. You're welcome.

[@pmpkmc]

I would guess at higher pressure (5-7 bar) that more wax is being forced in to the wick then can be efficiently burned and this is the reason for the smoke and soot. where at the lower pressure (2-3 bar) there is a relatively higher concentration of O2 to fuel so it lets it burns more completely and brighter.

[@Sparky_D]

I'm thinking the vessel is too small because it will quickly start to impead the flame due to a build up of smoke/lack of oxygen

[@iamzombie]

I wonder if the high pressure was forcing more liquid wax into the wick that was previously occupied by air, and that was making more soot?

[@ZMAN_420]

Nice👍🏻

[@jamesbrown4092]

I'm wonder how different gasses would affect the pitch of sound from your music player. For example, filling the chamber with CO2 from a sodastream bottle or with helium from a couple balloons.

[@ashesmandalay1762]

So higher pressure should mean more oxygen for the fire to burn, but because it's a small chamber the candle is eating the oxygen too quickly while it is still being pumped in with normal air to increase pressure, so by the time its under high pressure most of the oxygen is already consumed. I wonder if there's a way to light the candle remotely inside the chamber so you can bring it up to pressure and then start it.

[@jonathanbates9928]

Im curious whether or not the flame would last longer in the higher pressure. More oxygen, but would the extra pressure effect burn time?

[@superawesomefuntime2162]

What about a high voltage plasma arc in high pressure?

[@Transit_Biker]

More oxygen in the air, but also no fresh source, so it was constantly changing the composition of the air in the chamber. Basically a very slow internal combustion engine. If there was a way to increase pressure while cycling out the stale air, that would be better for this test. A cleaner burning fuel could also be an option.

[@John_Morton]

Does opening the ball valve put the flame out, or launch the candle accross the room?

[@moefuggerr2970]

Who knows. It was sucking up the oxygen all the while the pressure was increasing and decreasing. .

[@ataricom]

"I'm not sure we learned anything." But we still had fun!

[@kobold2183]

Super

[@Bagline]

more pressure, more density of oxygen available and more available overall, so faster burning and brighter? I suspect that It gets dimmer because the oxygen is still running out. You should try to find a way to light it remotely after the pressure difference is achieved. Cody's Lab did a similar thing in low pressure. He used a strong laser through the viewing window to attempt to light it.

[@u.e.u.e.]

1:13 Is this an IKEA Original or not? 🤪😂

[@michaelbraaten]

It seems to me you’re trying to home-brew internal combustion (poorly) but you don’t have enough pressure to make it happen lol I love these experiments, though, don’t get me wrong! 😄