Thermo Acoustic Engine

This single cylinder thermo acoustic engine operates from a tiny methylated spirits (denatured alcohol) flame. The optimum running speed is 2700rpm when warmed up fully. As far as we know this is the fastest thermo-acoustic engine available.
The thermo acoustic engine is known by several names, including resonant engine, lag engine, lamina flow engine and traveling wave engine. This engine, with its transparent main tube, beautifully and elegantly demonstrates the principles behind such engines.
How does it work?
The thermo-acoustic engine works by converting sound waves into motion. The sound waves are generated by heating one end of a 'stack' of coiled material and allowing the other end to remain cool.
The engine is fired by a small spirit burner. By heating the end of the coiled 'stack' a bouncing pressure wave is set up inside the tube. The crucial element in the thermo-acoustic engine is the 'choke', which reduces the bore of the tube.
It is the pressure fluctuations that ultimately drive the engine, in the expansion phase the piston is pushed outwards, in the contraction phase the piston is pulled inwards.
The engine requires a small push of the flywheel for it to start. Without the small push the pressure and velocity of the standing wave remain at equilibrium. Move the flywheel and the equilibrium is shifted, thus allowing the cyclic variations to take place.

[@grandillusions]

The engine will actually run in either direction, it just depends on which way you spin the flywheel at the start.

[@biswajitpaul25]

You got some science there Tim. And it's awesome

[@AI_GAMER_GUY]

Can't believe this had no replies in 8 years

[@foureyedchick]

Put a little electric motor as a starter. Use a little battery to start the engine and put a tiny alternator to keep the battery charged, lol.

[@gagekieffer772]

@@AI_GAMER_GUY I mean, I don't even think replies were a thing eight years ago

[@Linkophere]

@@gagekieffer772 in fact they were not. You had to type in thier usernames the start of a comment to tag them in a way

[@Kroitk]

Thanks Tim, next time a cop busts my ass and asks me about my crack pipe I'll just say it's actually a thermo acoustic engine

[@Cacowninja]

+Kroitk Do you smoke crack?

[@Kroitk]

+Fell Man Am I being detained? Am I being detained? Am I being detained?

[@Cacowninja]

Kroitk No I'm just curious.

[@Kroitk]

Fell Man That's what a cop WOULD say

[@Cacowninja]

Kroitk Well you mentioned the crack pipe thing, but if you don't want to say anymore, then I'll just go.

[@TheRipplaya]

Tim trying to blame the flame for the spin, we all know that you just used so much force that it seemed to be spinning forever.

[@Kuroganekisaki]

Tim accidentally used 10% of his mana when he touched the engine. Rumor has it, it's spinning to this day...

[@JudgeNicodemus]

Tim used the Zeppeli family ultimate technique. The infinite spin.

[@imhere1303]

Tim probably used some sacred demon sword technique and treated his own body as the blade

[@thegreatzoom5073]

@@JudgeNicodemus he spun it in the golden ratio

[@RecreationCertified]

#flatearthsociety 😂

[@jakethetool698]

Just wanted to say thanks, for the entertaining content. Amidst the days of late, your videos seem to yield a breath of fresh air.

[@hailsatyr]

I made a mistake of watching one recommended video from this channel, now my whole feed consists of these

[@gumbuk9769]

That's where you are mistaken my dear friend. *It was not a mistake*

[@gurgy3]

The blessing of Tim is upon you

[@MapleMaf1a]

Mistake??

[@animula6908]

You say that like it’s a bad thing

[@Dicklefart]

Are you unhappy with your decision? I’m not, we are al blessed by the holy Tim

[@Cananalope]

amazing.. I must say, it does look like some type of automatic crack pipe.

[@niftyrmz4506]

That's what I was thinking a mechanical crack/meth pipe

[@Picolown]

You killed me with That one Im going to sleep now

[@CHITOWNDEECON1]

I bet he's got the fake rose in his pocket still

[@banditoincognito8950]

lmao you know opiates were really really popular as a drug.

[@doctapeppur1900]

@@banditoincognito8950 crack isn't an opiate lmfao

[@henriknykvist]

Looks like an advanced crack pipe.

[@jaydensteventon4920]

Lol XD best comment

[@ChuckT117]

Funny asf

[@MickeyD2012]

EXACTLY my thought.

[@cloudchaser8297]

Im scrolling thru this whole video to see how many crack pipe references there are. This is the 12th one so far. ....to be continued. Can you imagine this guy removing the tube , putting on a huge square of crack hitting it then 7 minutes later after he comes back down from space say....Absolutely marvelous .

[@Mate397]

Will the footage material be in the test? I can't fail advanced crack pipe this semester!

[@PantonePapi]

This is the craziest dab rig I've seen

[@dyingangelo]

+cingratta low temp bre

[@MrIzo56]

Tepry as fuck bruv

[@freshproduce2170]

chill out brug

[@BrickfallOfficial]

I will pay you to read me bed time stories, i don't care if i'm an adult. You're just so damn charming.

[@mileslasee8293]

I know right

[@mileslasee8293]

I know right

[@mason386]

I know right

[@BlueBeamProductions]

I know right

[@neversurrender5798]

+coconut7joemanji I know right

[@kanecobe]

0:02 about to hit that bong but you play it cool.

[@ryedj707]

When the video started I knew the top comment would be about bongs...

[@dyingangelo]

+Kanecobe puts the mouth around the bong"

[@zsolttildy5742]

lmao

[@lukewarmcocoa5421]

#test

[@TheLpd1]

HAAHAHAHAHHhh

[@daniraspahic2625]

I really like his voice and simple way of explaining. Great presentations.

[@oatmongen4263]

This sounds really efficient. There is no exhaust, so none of the heat which is trapped within the tube is wasted. Only the energy that matches the standing wave conditions, and the conditions of a mode hop will escape.

[@cubey]

The exhaust comes off of the flame. Very inefficient actually since most heat is unused. It's like a vented gas heater vs an unvented gas heater. You lose some efficiency with it vented, but unvented has the combustion gases (exhaust)

[@smithsmith6402]

@@cubey Sure but the flame being exposed like that is just to make it look cool and easier to play with. If you used a proper setup to focus the heatsource on the tube, the waste would only be from the cold side of the tube radiating heat and your other usual entropy losses in an imperfect system. I'm curious how much of a loss that is. That said it's probably not THAT efficient, hydrocarbons are just very dense energy sources. But it seems pretty good for such a convoluted method.

[@vhsfilms5577]

I'm glad I'm getting a lot of this recommended

[@spoopyscaryskelebones3846]

As do I.

[@KarstenJohansson]

Very cool. I've never seen a thermo acoustic engine before. It reminds me of the first time I learned how to build a little table-top pulse jet. It was (and is) like magic.

[@ahmarsaeed6085]

The contraption is beautifully made.

[@RobB-vz2vo]

Just in case people were wondering, there are two classes of Thermoacoustic Engines; this one is a standing-wave engine (Sondhauss Tube) and the other is a travelling-wave engine (Stirling Engine). This video title is more correct if it's named 'Sondhauss Tube Thermoacoustic Engine'

[@jacksacku]

dis guys voice is just awesome

[@zbyszekkopec908]

Fajny zmodyfikowany STIRLING.

[@nonameyet3783]

This is 8 years old and the video quality is impressive!

[@koettfaers]

You make 2013 sound like it was the 80s, wtf are you on about

[@Scottymatic]

You're right on the first point. What he has there is a Beta Type Stirling Engine. However, there is such a thing as a thermoacoustic enging, which uses acoustic standing waves to push the actual internal fluid in a Stirling Cycle. It has fewer moving parts than a Stirling Engine. It converts heat to sound, or vice versa.

[@vedanshmodwel]

"That's a nice noise." Best intro ever😂

[@bilal00276]

before i watch the video, is it extraordinary?

[@bilal00276]

yep, 0:13

[@davidharasymowicz8707]

it's a very clever idea...

[@julesschul2640]

amazing concept

[@allseriousness]

very sweet

[@ancientaliensarecoming7201]

Bilal Patel no

bu adamın ses tonu çok dinlendirici yaw..resmen uykumu getiriyor.abone oldum sırf o yüzden.

[@hopisanka4430]

i could watch this piece for days

[@MrIzo56]

Please make a series of audiobooks my good sir.

[@snakerman2612]

It's a Stirling engine, give the man some recognition

[@pvtsparkplug2489]

Such an old video but sparked a very curious and growing want for one and even cooler ones now

[@amitabhakassap7339]

you are showing us great things; please keep up the good work.

[@anmolgarg5133]

0:10 his voice is so relaxing, but his eyes says: "you are a disappointment for your parents" 😅

[@Kevill]

Well, I need one of those now...

[@heyassbutt7668]

Good job, Tim

[@evil17]

Nice little engine, and fairly quiet too!

[@bee9679]

it's actually much louder inside the tube!

[@meunome5867]

It's called Stirling Engine, and it's known to have the greater efficiency, by that means, It's also the engine that resembles Carnot cycle.

[@kennethsizer6217]

They are both very interesting heat engines, but thermoacoustic and Sterling engines are two different things. See: en.wikipedia.org/wiki/Thermoacoustic_heat_engine and: en.wikipedia.org/wiki/Stirling_engine

[@kickinbackinOC]

Very interesting, thank you. However, the action of the hot air and the piston could have used more of an in-depth explanation. I suspect the expanding heated air is pushing the piston outward until some port is cleared, releasing the compression. Next, I suspect that the flywheel (now in motion) forces the piston back into the compression chamber", and the process repeats. There is no one blowing into the tube, of course. The harmonic resonance explanation misses the issue of the movement of the piston. The engine is not working on audio resonance, it's working on expanding air. "Similar" to the action on a steam locomotive, which is a better analogy then blowing into a bottle. But again, I enjoy the videos very much, and I thank you for another thought-provoking episode!

[@bmerigan]

Wouldn't that explanation run out of air inside the tube?

[@sylvainrichard6679]

Ben Merigan fast, fast fast... Emptied your brain brain brain,,,

[@dsthaipola2611]

the piston is moved by a standing wave inside the tube, NightHawkInLight has a great video explaining this

[@JoKohut]

nice piece tim!

[@Menegoth]

What a soothing noise.

[@thesodathief]

"Damn cuz, this kush too entirely loud" -Tim

[@Jts441]

could you wrap a heating coil around it for the same effect?

[@PRABHRATTAN]

Nice Work

[@planktonfun1]

Moooom! Tim's at it again

[@mcmillitint]

Thats pretty dope, idk how my boss would feel about me having a burner on my desk though

[@ignazioacerenza9881]

My girlfriend: let's do it slowly. Me five minutes later:

[@GothicLeviathan]

Jesus🤣

[@yashpandey3.3.3]

@@GothicLeviathan does he become jesus five minutes later????!!!!

[@erickramer5987]

I love it!!! Thank you Sir!!

[@szabolcsszigligeti1565]

This is so peaceful.

[@Pokajoka773]

These videos are like ASMR. I feel like I could listen to him showing toys forever.

[@mtothem1337]

It looks like a fancy crack pipe.

[@Mogliz0rz]

only the best for Tim.

[@Mister_NO.]

hahaha that.. :)

[@rickhartman2106]

IT DOES !

[@slinkytreekreeper]

Interesting description of a standing wave you used. Never thought of it in those terms as it's not electricity or radio waves but I dig it.

[@ADjustinG2013]

Tim: this fascinating little device is what they call a "crack pipe". It helps people get high. Brilliant idea.

[@Tocen]

Is it possible to apply this in large scale in volcanoes for unlimited energy?

[@texannationalist5887]

uh, probably

[@davidharasymowicz8707]

aint burning forever dude. The fuse will go out eventually. Plus, that little thingy aint spinning that hard, which means i dont think it will generate that much energy. Correct me if i'm wrong 😉.

[@texannationalist5887]

true, but the heat of the volcano will last much longer than most sources

[@MarianKeller]

Generally, yes. Although thermo-acoustic generators aren't currently used commercially, geothermal power plants do actually generate "unlimited" energy, as long as the earth is hot.

[@ristopoho1383]

There has been tries to use those in larger scales, though the mechanism is actually quite delicate, and most larger ones tend to run too fast, and break themselves. As an idea, it does work, and a lot of effort goes into making it real. Still, as of now, there aren't any working ones producing much of energy(as far as i know). The big problem with thermoacustic engines in energy production is their large size compared to the energy production. Also, on the good side, the models, mainly stirling engine, work on actually a really small temperature difference. So using dangerous things like volkanoes isn't necessary.

[@izzyAKAisra]

i never heard of this before

[@cappin6937]

My dad had one of these! Same concept except it was a small train and the wheels turned when you started it

[@TheGeekazoid]

You have awesome videos well done sir

[@ChristopherSmith-bh4sz]

Fantastic presenter but totally wrong, this is an engine working on the Sterling cycle. Rayleigh discussed pumping heat with sound. Thermoacoustic engines (sometimes called "TA engines") are thermoacoustic devices which use high-amplitude sound waves to pump heat from one place to another, or conversely use a heat difference to induce high-amplitude sound waves.(Wikipedia)

[@joshc1386]

What is the difference between this and a sterling motor?

[@nateb3679]

Can’t smoke crackrock out of a sterling motor

[@belofostio8494]

It is the stirling motor beta type. Not thermoacoustic. The original version has 2 cylinders.

[@onlineidentity6826]

That is truly a thing of beauty.

[@TheFellerHasAChannelGodDamnIt]

Nice bong my dude 👌😎

[@Soniphex]

Has high rpms, but probably has nearly non-existant torque. Although I can see this being used in a power generator; on a larger scale of course. I actually think that could be pretty efficient depending on how long that fuel source lasts. Interesting little machine that thing.

[@Mercury2wo]

I don't understand the "sound wave" principle at work here? This is a Stirling engine - working on temperature differential. What's the relevance of the "sound wave like in a bottle" here?

[@pauls5745]

Mercury2wo I agree, there is no acoustic force at work here. It is pressure due to heating. Wind on a bottle is resonance of the volume of air (flutes use this). not in this Stirling engine, a predecessor to the steam engine. thermal air pressure is not acoustic

[@Thinnestmeteor]

Mercury2wo Yup, Stirling machine, no sound involved here.

[@JamesDM_]

pds tech Sometimes intelligent people do not consider that they can be incorrect. Directly from Wikipedia "Thermoacoustic cycle Thermoacoustic devices are very different from Stirling devices, although the individual path travelled by each working gas molecule does follow a real Stirling cycle. These devices include the thermoacoustic engine and thermoacoustic refrigerator. High-amplitude acoustic standing waves cause compression and expansion analogous to a Stirling power piston, while out-of-phase acoustic travelling waves cause displacement along a temperature gradient, analogous to a Stirling displacer piston. Thus a thermoacoustic device typically does not have a displacer, as found in a beta or gamma Stirling." en.wikipedia.org/wiki/Stirling_engine

[@Thinnestmeteor]

James Blanchard I gave it a quick look. Very interesting but the motor shown here still looks nothing like what I have in mind for an acoustic motor. Now that I look at it more carefully it doesn't look like a stirling motor either. I don't know... There are a lot of thing why I don't see this working with standing waves, like the steel wool in the tube disturbing any wave trying to travel there. In my mind it can just work with a combination of inertia and gas expansion. Please I would love to discuss this to sort what kind of machine is this.

[@Jeffrey314159]

+James Blanchard Sometimes intelligent people believe whatever they read on wikipedia, a populist website. The Steam Engine was invented first and was being used in early 18th century England to pump water out of a mine. In the early 19th century a minister called Stirling was appalled by the fatal accidents these steam engines would wreak when the high pressure inside would cause them to explode occasionally, so he invented his low pressure external combustion engine.

[@otakuribo]

You do the world a service.

[@raykent3211]

Tim's account is correct. This is a resonant hot-air engine. Not a Sterling engine. Not a solution to the world's energy problems. Inefficient compared to true Sterling engines, but fascinating, and therefore of value.

[@OfficialSNIxn]

Isnt this just a sterling engine?

[@GoldenHay1]

+Liam Weaver Yes it is.

[@johnjones4825]

+LineoLemon No it's not.

[@benaloney]

+John Jones why?

[@johnjones4825]

+benaloney A sterling engine uses 2 cylinders...runs on the pressure/heat differential...

[@bopsouttaopps]

+John Jones False, one cylinder one displacer. This is a stirling engine

[@timsmith1118]

i dont fully understand the acoustic part of this engine...has sound got any effect at all?

[@McJaews]

Sound is just the word we've given to the energy waves that resonate with our ears. The "thermo" signifies the change in temperature, and the "acoustic" part is referring to the frequency of high and low pressure states of the piston. When the piston is closest to the hot part of the tube, the temperature is at its lowest and so is the pressure and vice versa. I hope that helped:)

[@timsmith1118]

right i see thanks, but then shouldnt a normal internal combustion engine be also named as 'acoustic'?

[@McJaews]

Well. I'm not an expert in this, nor am I an engineer, so I don't know the exact answer to your question. I imagine that the reason for the different names is that the internal combustion engine works differently. In those, an explosion is triggered by a combination of a spark and high pressure air, which then forces the piston outwards, which gives the engine its name. the acoustic part may not apply here because every time the piston moves it's because of a trigger (explosion!) and not because the heat and pressure differences maintain a standing wave.

[@timsmith1118]

alright, makes sense

[@IvanIvan1974]

The acoustic part is the guy who talks.

[@CHITOWNDEECON1]

I'd love one of these as a phone charger

[@nathncassieosborne6094]

I'm working on a engine that will use a similar principal but has fair few differences in its operation is source and return and re use of energy of its motion using pressure difference reaction this has given me some more ideas to help ty just by chance I seen it as well :)

[@LetsTakeWalk]

This looks like a Stirling engine to me.

[@yoloodevil4170]

thought it was a crack pipe

[@henrycorbitt2244]

Striking engine is really similar but it would take a lot less energy whereas this needs a flame

[@GabrielLopez-mo2xo]

@@henrycorbitt2244 there are several setrilings that use flames to increase output

[@henrycorbitt2244]

@@GabrielLopez-mo2xo that’s cool I didn’t know about that

[@jay7264]

i want that

[@darthfrootloops5041]

That was sooooo satisfying

[@TheMegaWeazel]

These videos help with my emotional damage.

[@funny-video-YouTube-channel]

*Why is that acoustic ?* Seems more like thermo-kinetic. It converts heat into movement = kinetic.

[@CheseWhelie]

"The thermo-acoustic engine works by converting sound waves into motion. The sound waves are generated by heating one end of a 'stack' of coiled material and allowing the other end to remain cool."

[@odeytayem8902]

I agree.. it’s just the heated up gasses pushing on the piston from the inside

[@JMRabil675]

Odey you dont understand the science behind it.

[@odeytayem8902]

@@JMRabil675 please explain

[@MarkJT1000]

@@odeytayem8902 Yes please do cos I can't understand where the sound comes from. I couldn't even hear any sound.

[@ne1cup]

if they just made one that sounded like a Harley?

[@ch34pwoowoo7]

Why is it always the 8 years old videos that are interesting as heck

[@user-qi6oe7jh2c]

Стерлингов двигател нагледно 👍👏👏👏👏

[@jonathanmellqvist2]

The purchase link doesn't work!! :(

[@myrtopolyzou4622]

isnt the thermoacoustic engine supposed to create sound as well?

[@sonicspring6448]

I don't think it's strictly thermo acoustic. If the flywheel rotated at 2,400 rpm, for example, the frequency of the piston would be 40x per second, and that glass tube is way too short to resonate at that frequency.

[@GabeDoesStuff5432123]

A delightful trick!

[@Bipedalius]

Wow, that's pretty awesome.

[@landenkugler7906]

This has got to be the fanciest crack pipe I ever seen

[@haydenadler3147]

it’s 2021 what are we all doing here

[@bangleyjelly]

Lawrence of arabia smoked crack, every brit had fancy crack pipes in Victorian times

[@ericyi5661]

I didn't expect it to rotate this fast 😅

[@iueras]

A Stirling engine works by moving a heated and cooled working fluid, such as air, exploiting the thermal input to create work by compressing the cold air and expanding the hot. The Raleigh device works by producing relatively high-amplitude sound waves from the heat difference, and using those to cause motion in the piston. The working fluid is only used to carry the compression wave, creating both compression (at peak) and expansion (at 0) without having to actually move the fluid.

[@seanzappulla71]

I would like one of these.

[@cardiod]

What does this have to do with acoustics? Is this not just a basic example of thermodynamics where heat energy is transformed into mechanical energy (eg. heat increases air pressure -> air does work on piston)?

[@LysergicAcids]

No the sound waves are what move the piston, specifically high-amplitude sound waves. An increase in air pressure would cause expansion but not contraction, it is the difference in heat that allows for induction of sound waves.

[@owletkami8018]

Isn't that just a simple, I think Alpha configuration, Stirling engine?

[@ohsnapitsgeneva]

+Owlet Kami my thoughts exactly. Where does the acoustic come into play?

[@ChuckT117]

Another name for it

[@hobbified]

No, any Stirling engine has to have two pistons (whether in one cylinder or two) with a fixed phase relationship between them to be able to do work. This replaces one of the pistons with an acoustic waveguide that serves the same function if and only if the engine is turning at the right speed to set up a standing wave at the waveguide's resonant frequency. That's why it turns at a consistent speed, and that's what's "acoustic" about it.

[@owletkami8018]

+hobbified That solved my question definitely, thanks.

[@mnhusin509]

it's definitely alpha stirling engine, with single tube it can't move like that, if it only one tubing, the expantion of heated air inside will never compress it back because of vibration and friction loses, the only answer is the second piston is inside the tube that mounted by flywheel, that why there is a black pin on the crank that assembled 90 degree from first piston rod's pin. sorry but if there is only one piston it will break of thermodynamics law

[@jaquinlopezz9825]

Bloody hell thats brilliant

[@grannysvids]

Nice little gadget!

[@crisitoadvincula]

That is a Stirling Engine!!

[@parkeypence5974]

This guy could say "I'm sorry, your mother is dead" and if he was using that same voice I would ask him to say it again.

[@icyBulls]

This is was the first ever of his videos I ever watched

[@SLACKLINEDUDE]

grand illusions talking about standing waves? You have my respect.

[@GirGir183]

0:21 I'm hardly the only person who sees a crack pipe here.

[@smittywerbenyeagermenjenso3720]

Literally every comment says that now

[@kunal1920]

You watching in 8k

[@isaaccarpinteyro7937]

Seems more like a Sterling engine.

[@chickenwing8172]

I love this man

[@ubayyd]

That rev though

[@MrBigangry]

That is a sterling engine i dont know where you found the name thermo acoustic

[@RolyWilliams]

It's not a Stirling engine; it has only one piston for a start. It works on a completely different principal that I don't understand.

[@0boy00]

Roly Williams ha ha that killed me.

[@flurf5245]

Roly Williams The heat takes air inside the tube with black stuff and causes the piston part to go in and open a door for air to go in, and I think the air helps push the part out to close the door, and then suck the air again

[@MrBigangry]

I'm no expert But i see air expanding and contracting moving a piston the contracting to me seems like the steal wool being used as a heat sink. As far as i know that is a sterling engine. As far as i know a sterling engine does not need any more than one piston.

[@MrBigangry]

Wikipedia calls it a beta stirling engine and i have seen this type called a sterling engine before.

[@ferretyluv]

Why is it thermo-acoustic? I get the thermo, but why acoustic?

[@peglegnoid6139]

+ferretyluv Turn up your volume and you can hear the motor run, acoustic..

[@chaotixthefox]

A standing acoustic wave and a traveling acoustic wave perpetuate the motion of the piston.

[@odeytayem8902]

@@chaotixthefox acoustic energy is just a fluctuation in gas or liquid molecules but so is combustion.. an explosion can be considered ‘a very loud impact noise’ in someway. It seems like a simple combustion engine to me

[@chaotixthefox]

@@odeytayem8902 key word: standing

[@mahimsd7645]

best Engine I HV ever seen ...

[@zfikrimm5179]

I like the sound of engine😆

[@attianotattia3470]

A New drinking game : Drink everytime this guy says extraordinary.

[@williama.737]

+jason handers his. name. is. tim.

[@jonah4295]

never explains how they work unfortunatly

[@Blake-id6yd]

I love this old man.

[@adamsadventures9919]

Love it...danke!