paulofor
196244
4342
172
They make a hole in all caps.
A Simple Idea That Makes Lives A Bit Better
Feb 26, 2018 12:48 PM
paulofor
196244
4342
172
They make a hole in all caps.
A Simple Idea That Makes Lives A Bit Better
Blastergv9
The thermodynamics are illustrated incorrectly, though the end result is correct. But, simple ideas like this change the world
Flyndaran
So much time and effort spent on placebos. :(
wabewalker
This feels like one of those Kickstarter ventures which require some debunking, à la WaterSeer
Marty40k
When bad physics and a desire to virtue signal meet in a lovely scam. But Waterseer still wins as far as stolen money goes.
fadecomic
FYI: this is exactly the principle your home AC works on, just with pumps and chemicals to improve heat exchange.
LOlivingVE
It’s exactly the Opposite of how an AC works...(DE-compression cools the radiator and the fan blows air across the radiator )
smellyshorts
Covering the window probably helped a lot.
DiracsDelta
It did. It will be cooler inside than the outside air temp.
TheMayorOfTittyCity
I'm no physicist but doesn't this look like something that doesn't work?
Ibringchocolate
If you compress hot gas it will increase it's temperature. (at least it does so around here)
LOlivingVE
Oooohh you must be in the Western Hemisphere. In the Eastern, it’s backwards. And in the South Western. Very scientific. Much truths.
Roehcai
So, it's the physics equivalent of the placebo effect. Huh.
manowar669
How to make your house whistle like old lady farts
mbHogmountain2017
Yeah, this doesn’t work.
yacko69
Fake.. Fake !!
anacostia
http://laweinstein.com/blog/heat-transfer-thermodynamics/debunking-the-eco-cooler/
steve3p0
Compressing air doesn't cool it...
Ruhig
Is that really enough compression to make that much of a difference? I'm kind of skeptical...
cosonfused
Wasn't this debunked and purely because they covered a window?
TinyRocktopus
Yea it just blocking sunlight and providing airflow so it works it's just a really think screen door
GahDuma
This isn't better than poking holes in your wall or OPENING A WINDOW
warick
Step 1: Cut a hole in the box.
ListlessGeek
howlinginpain
Step 2: Put your junk in that box
MisterValyrianStealYourGirl
Step 3: Push some air through that box
MrRobSteel
Instructions unclear, stuck in box, no hole, air running out, send help.
howlinginpain
Natural selection at its finest.
PancakeLuncheon
Kyman201
Oh thank god it wasn't just me.
DigiRust
Hells yeah
JakeBeller
Compression increases temperature though....
JakeBeller
The correct idea is that this is a airflow increase having air move most swiftly into and out of the home resulting in lower ambient temps
JakeBeller
Temperature drops because hot air isn't staying in the confined space long enough to raise the temperature. Think blowing on hot soup idea.
rookiefdb
woah cool!! ill keep chuggin sodas fpor mankind
RetardAIert
Should just install some air conditioning.
TheAssassinArtemisEntreri
Totally, central air will fix all of that. They can run it all day and turn those bottles around and cool the neighborhood. Problem solved
RetardAIert
Prepare for the downvotes of people not understanding sarcasm.
Conlo5
I believe 115 - 94 is more than a 5 degree differential
mouseasw
I was going to reply that it's a 5 C drop, rather than F, but the picture has it at 45 C before, and 35 C after, so...yeah
lotsofpulp
narcolapser
Fake science just like Bill Nye is a fake scientist.
Skizmo
TallDude
Bad science. Doesn't actually work the way they claim it does.
OverzealousDude
Jupman
I love how people make her out to this, but from interviews see seems pretty chill and a typical cali rich girl
mrmartini
What's the difference between what people are making her out to be and "typical cali rich girl", regardless of chill levels?
LOlivingVE
I’m guessing “she’s not actually a stupid cunt, she just sounds and looks like it”? Seems to me she was a dumb teenager/early twenties (1)
LOlivingVE
W way too much publicity and money(like the Kardashian/Jenners but with no guidance) and now she’s older she kinda makes fun of herself
Sallvo623
Fake
Jollymeadow
I have no idea why you're being downvoted. The shirt originally said "stop being desperate" before it was photoshopped.
MyGFMightLikeTitsMoreThanIDo
And yours is upvoted. Now compare his response to yours. What do you see?
MidnightAtMandS
Err.. actually explaining yourself is better than just giving a one word response?
MyGFMightLikeTitsMoreThanIDo
Upvote
GreyKihano
I have few get rich fast schemes, but involve few people dying.
BROKES
Hmm this merits a follow up
NamelessFacelessAverageJoe
Befriend tons of people, start an business on paper than buy them life insurance and kill them?
sometimesipostsockshere
Lurk tor web and advertise your services as a hitman. Deliver jobs and acquire currency. That would be a plan of mine if I'd be up to kill
NotSoArtzie
And then one day you take on a job with a compensation never seen before. You accept in a blink. The target's name is revealed. It's you.
GRex2595
Never accept full payment without knowong the target. Always reserve the right to say no at any time.
sometimesipostsockshere
You panic. Then you start to think rationally again, plotting your way out. Next few day pass in quickly. Maybe even a week.
dantesupertramp
It's fake http://laweinstein.com/blog/heat-transfer-thermodynamics/debunking-the-eco-cooler/
LeviTheRevelator
So they're just putting it in backwards.
Varzoth
Did people think it was real? It's some fucking pop bottles in a wall it's not going to magically cool anything.
mechanicalchaos
I know shit about this type of physics but if it worked you think we'd see a lot more design implementation elsewhere. Like in as the
mechanicalchaos
front of our cooling fans. Or as a large wall for an outdoor recreation area. In modern designs, ancient designs... just anywhere.
the4getful
Wait... do we need Thunderf00t to help us debunk this?
ktrout30
This is wrong. Fluid flows through nozzles experience a temperature drop. This is basic thermodynamics.
ktrout30
Don’t pass off bad blog posts as actual scientific analysis.
benayises
If you were correct fridges would be used to cook food
ktrout30
That doesn’t make sense and I am correct. Nozzles flows decrease temperature of the fluid via conversion of enthalpy into kinetic energy.
benayises
fridges work by expanding air that has been previously compressed and allowed to cool, 1/2
benayises
kinetic energy has nothing to do with it and enthalpy isn't even a word that can be used in that context
GuessIdo
IN ALL CAPS YOU SAY?
iamspartan1262
IN ALL CAPS!!
TheSpeakerOfTheHouse
Well they don't accept NCR money.
ALLCAPSDUDE
YOU CALLED?
MySpiritAnimalIsTheUnpopularOpinionPuffin
A-HOLE in all caps.
Holdshift2countercaps
Sorry what?
PotatoIsland
YES A HOLE IN ALL CAPS https://qph.fs.quoracdn.net/main-qimg-d46dec0fd90b5adfef92f54c73241905-c
ItsLuke192
UPPERCASE LETTERS
ALLCAPSDUDE
MY LONG LOST ALL CAPS BRO
ItsLuke192
THIS IS CRAZY
MetaSomma
THEALLCAPSWARRIOR
WOO I AM RELEVANT
ItsLuke192
ITS THE CAPS FAMILY REUNION @ALLCAPSDUDE @THEALLCAPSWARRIOR
CanOnlySayYes
THERE IS MORE OF US @ONLYCAPITALLETTERS
mentallychallengeaccepted
OMFG I THOUGHT I WAS THE ONLY ONE
ALLCAPSDUDE
Logan9Fingers
MAD VILLIAN
naPalm00
ALL CAPS WHEN YOU SPELL THE MAN'S NAME
WolnyLogin
Logan9Fingers
Aww hell yeah
paulofor
YES, THAT'S WHAT I MEAN.
ALLCAPSDUDE
IM PICKING UP WHAT YOUR THROWING DOWN
ThatLizardThatRunsOnTwoFeet
NOT ON MY WATCH YOU DON'T
Danishlmgurian
WHY ARE WE DOING THIS
cthulhuOverlord
BECAUSE WE CAN
KiltedCurmudgeon
Zach538
ALLCAPSDUDE
ITS IN MY BLOOD
Boatsntoes
Compressing a gas raises its temperature. Think of a bike pump and how hot they get after a few bikes
DavidBrooker
Yeah, nozzles expand gases, they don't compress them.
Molotovbliss
https://en.m.wikipedia.org/wiki/Adiabatic_process
Molotovbliss
But the air coming out of the nozzle is cooler. Basic principles of this design. It does heat up first but then cools in small hole outlets
limbodog
I’m glad I’m not the only one who saw this as a problem.
AMartianPotato
That's actually exactly how it works. The air is heated as it enters, some of that heat is absorbed by the bottle. The air enters the >
freecookiessz
There's no way this works, plastic is not a good thermal conductor. And even if it did 5 degrees in a huge room because a few bottles lol?
AllTheGoodOnesWereGone
Yeah, that panel would need to be dissipating around 1KW without any of it leaking into the room lol.
AMartianPotato
room, expands again and therefore cools to a temp lower than what it was before. The excess heat in the bottle is dissipated outside >
AMartianPotato
by air flowing over and around the part of the bottle sticking out.
DiracsDelta
That is not the dominant effect. Combo of Venturi and adiobatic cooling. I can show math if you like.
Boatsntoes
OK that may check out but I'm still not seeing much thermal change there.
HiddenSanity
I mean, it's only dropping things from 45 to 40 kinda deal.
nimdae
Around 10C differential is pretty impressive for this. Sure, 35C is not great, but it's tons better than 45C. Good on these smart people.
tachometer74
I lived in Tucson in a house with a swamp cooler. It dropped the temp 20 degrees. 118 outside, 98 outside. Still sucked but was better.
FromMatterSpace
it would have to be pressurized. not enough pressure from wind to reduce temperature.
PoliteButFactualCanadian
How does compressing a gas lower it's temperature? I call BS on this invention.
VoyagerWasTheBestTrek
this method is exactly how the every AC (cars or home) works. Push a hot compressed gas thru a small hole, gas expands, temperature drops.
squintish
Expanding a compressed gas lowers the temperature.
NotquiteThereyet00
Fuck now I gotta convert to F
sharerimagethesimple
* (9/5) +32
etcnotect
÷5/9+32
Shamorza
What the °F is wrong with °C ?
NotquiteThereyet00
‘Mercia
Callintryluck
yea 113 to 95 F is a pretty significant drop by your observation.
TheGoldenPig
To us Americans, it's a drop from 113*F to 95*F. So like moving from Death Valley to Miami. :D
RoseTheSpecialEdTeacher
As someone from Palm Springs and a ridiculous electric bill...i need this.
squintish
What you need is a 'swamp cooler' (evaporative cooler). Basically you get air conditioning for the electrical cost of running a fan. (1/2)
squintish
They work very well in dry climates, less so in humid ones. (2/2)
purdhapley
Thanks for the freedom units conversion
nipplepanties
Or Arizona daytime to Arizona evening time
Plaguestorm172
sadly its fake : /
oldarchive
Try it for yourself
Cataleast
The "try it yourself" test is based solely on the velocity the air is exiting your mouth. It feels cooler in your hand, but temp is the same
Plaguestorm172
that and placebo is a hell of a drug, look at the madness of homeopathy.
Plaguestorm172
It doesent work, it breaks the laws of thermo dynamics and physics.
Plaguestorm172
When you compress something it gets hotter, when you strech it, it gets colder, looks up rubber band fridge. https://youtu.be/lfmrvxB154w
Youareidiots
Yeah that's true but the fact is, at low Mach numbers (ambient wind) air is basically incompressible so that "heating" is negligible
mbcoalson
Mechanical engineer here. Compressing a hot gas will reduce temperature. Ref: Ideal Gas Law: PV = nRT.
PoliteButFactualCanadian
So, when I compress gas to say, run a fridge, the gas already becomes cool and won't be hotter then say, the kitchen air?
mbcoalson
Never mind I’m an idiot compression heats a fluid. This would make the air warmer.
thatnewguytho
What would happen if you stacked 2 together?
GiantEnemyMudcrabz
Double the cooling, so an average of -10C from ambient
whirrrrkachunk
AKCHYUALLY, that's wrong, because it's fake. Otherwise you could just stack as many of them as you want together and get infinite 1/
whirrrrkachunk
cooling, which violates the second law of thermodynamics. 2/2
GiantEnemyMudcrabz
No your wrong. It obviously cools by 5 degrees so each panel lowers temp by 5. Stack 63.6 of them and you’ll hit 0k assuming -5c average.
Cataleast
Seems a bit suspect to me. I can't think of a scenario where forcing air through a small opening would result in significantly cooler output
mbcoalson
Ideal gas law: Pressure * Volume = #molecules of gas* gas constant * Temperature. Forcing a warmer gas through a compressor is how AC works.
Cataleast
An AC is a bit more complicated system than just forcing air through a small opening, though.
mbcoalson
Never mind I’m an idiot compression heats a fluid. This would make the air warmer.
squintish
It might work if the smaller openings faced the outside.
Egggnog
No, you were right before. PV=nRT, so if Volume goes down, then temperature must go down as well.
Egggnog
Compression heats a gas because the pressure changes too. It changes with the air here as well, but the change in temperature is significant
Thisworldiscrazy
Sorry to be an ass. It's 5C difference
Souljah42
They just need to install more of them
missleadinginiformation
Butt I like ass
Thisworldiscrazy
Same here, but at times looking at so many asses cause me to act like one
nimdae
I know it notes 5 degree difference but the thermometers clearly show ~45C and ~35C. Unless I'm missing something.
Youareidiots
Yeah the video is fake
Qualtagh
I'd guess that the added text is the expected/average difference, but the image is from one (better) result.
Thisworldiscrazy
I am too blind to see that lol
IGotNothin
Looks more like 44.
MapedMod
Definitely.
namiasdf
44.5, you can accurately read one half the visible gradient, for the purposes of data collection.
IGotNothin
You may be correct.
Prebez
I don't get the thermodynamics. Won't the same amount of air occupying the same space mean increased temperature?
DailyBullshit
I imagine this as filtering out fast molecules or hot air
AllTheGoodOnesWereGone
Because it's nonsense? http://laweinstein.com/blog/heat-transfer-thermodynamics/debunking-the-eco-cooler/
Leithoa
Thank you. It's great people want to help but pseudoscience doesn't.
Horstaschio
I thought the ideal gas law stated that decreasing volume (compressing) while maintaining moles of a gas increases temperature and pressure?
TinyRocktopus
Yes but at the higher temp 50° the heat transfers to the ambient temp 45° then it expands back to atm pressure with less heat energy 35°
Plaguestorm172
so where does that tempreture magically go?
Baeloro
There are too many factors at work here for the cooling to be attributed to their solution
OddOod
it's fake
lespritdelescargot
Engineer here. That is exactly correct. This is total nonsense.
AllTheGoodOnesWereGone
Don't try to overthink it, the whole thing is bullshit. No way that thing is dropping the room temp 5 degrees. This is fantasy.
DiracsDelta
... it is very real, and I can show you the math if you like.
AllTheGoodOnesWereGone
No, I'm sorry, that panel of plastic bottles would need to be dissipating something like a kilowatt. If there was even a source of airflow.
DiracsDelta
The energy comes from the wind, and it is a matter of substituting ideal gas law into the Bernoulli equation. .
AllTheGoodOnesWereGone
http://laweinstein.com/blog/heat-transfer-thermodynamics/debunking-the-eco-cooler/
boopityboopboop
Try exhaling through a gaping mouth and compare that with a pursed lips. Same principle applies here.
DiracsDelta
I will write up an explanation with math example if people want.
12345six
.
DiracsDelta
In progress. It’s mainly just substituting ideal gas law into Bernoulli, but I’m trying to make a real world example
Duplodocus
Waiting for this
ImGonnaSquirtHnnnnnggggg
Doot
WolnyLogin
saintnicklaus
I may be wrong but I think it's the same concept as blowing air out of your mouth. The smaller you make your lips the cooler the air will be
LordHosk
If you blow with your mouth wide open the air comes out at once and you only feel your body temperature air from your lungs...
LordHosk
if you purse your lips the air in your lungs mixes with the outside air which is cooler. These things cant produce that much thrust.
saintnicklaus
What if it's windy?
dafunk2000
oued
can't help laughing at the nerds gif, it beats me every time
stilljustachicken
So much overthinking here. Look at the houses, those are fucking ovens. Every decent air flow will help decrease temps. 1/2
stilljustachicken
velocity of normal wind is too small, heat transfer caused by compression won't have any cooling effect. It's just about air exchange 2/2
rngrmss
I was thinking the same thing. But I think the mechanism for this to work relies on having a consistent stream of air in the room.
Snooj
And if air is moving fast enough to compress itself in the bottle, why wouldn't you just open up two windows and enjoy the breeze?
TinyRocktopus
Air above 95°F doesn't provide much cooling for people
YoureWaifuAShit
it will still cool you if the huminidy is low and you can sweat
thatpoindexter
Two regular open windows would make a greater difference in air flow than essentially a grid of pin hole size "windows"
DavidBrooker
If the air is moving fast enough to compress itself in a converging section, the flow is supersonic. It's nonsense.
Chupanebreated
Fluid Mechanics PhD student here. The air isn't compressing at those speeds, velocity increases as it moves through the nozzle. 1/2
Chupanebreated
Per Bernoulli, the pressure drops with the increase in velocity. Then the ideal gas law takes over and temperature drops.
eggDK
With you until the actual temp drop.. The increased velocity makes the flow more directional, reaching further into the room. The (1/2)
eggDK
forced convection then makes it seem cooler inside, just as when using a fan.. The thermometer shot seems bogus though IMHO..
Plaguestorm172
it is literally just the fan effect, the tempreture is not lowering at all, it is just moving the "body temp" air away from your body
Youareidiots
Obviously you're right about the mostly incompressible flow, but do some quick energy equation work and you'll see the numbers are way off
Youareidiots
the video is full of bullshit, so why do people still think their invention won't just be a glorified window?
plainoldfool
I'm not a smart math science guy, but open your mouth wide and blow. Now narrow your lips like you are blowing out a candle. Feel (1)
plainoldfool
the temperature that comes out. It is cooler when the mouth it narrower. Not sure how it works, but it does work
squintish
It's velocity. The increased air flow evaporates more moisture from your skin making it feel cooler.
nimdae
The illustration is not accurate. The relatively marginal rate of compression causes the air to only slightly rise in temp as it enters (1)
nimdae
But the exit hole has a bit of a sharper decompression, so it's the decompression that causes the air to cool.
PurityOfEssence
yes, thank you!
TomZarekVP
THe heat is conducted into the bottle caps?
rvriveter
Doubt it's significant at typical wind velocities. I think they're just ventilating the space.
etilauqa
Thanks I was starting to question my sanity. Illustration is for them.
turfdraagster
omg thank you. I didint think you could compress a gas AND cool it. its the other way around
LostLocust
But the decompression happens inside, so the heat is absorbed by the house. Doesn't sound that efficient. @Glassman62 explained it better.
nimdae
You are correct, which is why I upvoted his explanation. I just oversimplified it.
ktrout30
There is no compression/decompression. The flow is below Mach = 0.3 so it is incompressible.
DavidBrooker
We're dealing with single-digit or smaller percent changes in most properties (except for velocity), so that rule doesn't apply. 1/2
DavidBrooker
The Ma=0.3 rule is from the fact most mach relations scale with Ma^2, and 10% is a common engineering margin of error. 2/2
ktrout30
Instead the flow accelerates through the nozzle, gaining kinetic energy. Where does this energy come from? Internal energy of the flow.
ktrout30
Because the internal energy of the flow decreases its temperature decreases, as temperature is a direct measure of internal energy.
Prebez
Makes sense. Thanks for the explanation.
NCPBullet
And now you know how contrails are formed
Plaguestorm172
Correct, but the tempreture still has to go somewhere it does not just vanish, yes it could cool that very small area, but the area aroundit
Prebez
Not sure if this is serious, but you COULD fool me ;-)
ktrout30
As the air moves through the neck it accelerates, increasing its velocity or kinetic energy if you like.
ktrout30
This comes at the expense of its pressure and internal energy, which decreases temperature.
ktrout30
Former Thermodynamics TA
PersonalDildo
That seems like bullshit, why wouldn’t people use this in cars? Like having a 3inch intake and 2.5inch throttle body
UnpopularOpinionPuffinPersonified
Don't they? That's basically what a supercharger does.
Scotia
No it doesn't.
UnpopularOpinionPuffinPersonified
Take large volume warm air, compress and cool and put it in the air/fuel mix. Sounds like this concept.
TinyRocktopus
People do that's what a ram air intake is
PersonalDildo
No it’s not, a ram intake is just a short cold air, all it does is get rid of the air box, piping is still the same width
TinyRocktopus
I meant when a air box is placed in grill or hood to use the highest pressure air and reduce that down to the throttle
DavidBrooker
The temperature change is negligible; nozzles and diffusers are used for velocity and pressure changes rather than temperature.
PersonalDildo
If here it made a 10 degree difference that’s sort of a big deal
DavidBrooker
"If" - I know of no process by which this device could achieve the cooling they claim. And the mechanism they describe is definitely not it.
Glassman62
Engineer. Compressing the air as it enters the neck temporarily raises the air temp. The bottle absorbs the extra heat and gets hotter 1/?
nimdae
I encourage people to upvote this explanation over mine, tbh. Mine is oversimplified and I'm not an engineer :)
OddOod
it's fake
houseofnifty
Thats not wrong, but I really dont think it'd make an appreciable difference. Calculate just how little it heats the air for example.
DavidBrooker
It is wrong. Nozzles don't compress air.
houseofnifty
U havin a giggle mate?
DavidBrooker
For an incompressible (low Ma) flow, a contraction (nozzle) requires the velocity of the flow to increase to satisfy mass conservation. 1/2
badspellling
I hope you don't work on anything important...
gewalt
what the fuck are you smoking? theres no way the bottle is going to absorb a significant enough amount of thermal energy to have any effect
squiddna
Thanks for this explanation!
TheMayorOfTittyCity
Wouldn't the bottle just reach its equilibrium temperature in like one minute in the hot sun and then do nothing?
TheMayorOfTittyCity
Also theres nothing forcing air through the bottle, its just passive wind. I doubt that would make any appreciable difference
DavidBrooker
Nozzles expand air, they don't compress. Pressure drops through a nozzle, which at a constant density does indeed reduce temperature. 1/2
DavidBrooker
However, this temperature change is likely pretty small and I expect most of the benefits here are from improved convection. 2/2
dantesupertramp
Depends on the direction of flow through the nozzle. Air in the small and out the big: expansion. Other direction: compression
DavidBrooker
That is not correct. A nozzle always expands flow. If you run it backwards, it is called a diffuser. You also have the process backwards 1/2
DavidBrooker
a converging section (for subsonic flows) is a nozzle, and expands flow. A diverging section is a diffuzer, and compresses it. 2/2
DavidBrooker
Since I'm not convincing, here's White:
(pressure decreases in a nozzle, ie: expansion)
DavidBrooker
Smitts:
(pressure decreases in a nozzle, ie: expansion)
DavidBrooker
Cengel and Boles:
(pressure decreases in a nozzle, ie: expansion)
DavidBrooker
Fox et al:
(pressure decreases in a nozzle, ie: expansion)
DavidBrooker
Moran and Shapiro:
(pressure decreases in a nozzle, ie: expansion)
Glassman62
Outside temps. Outside air blowing across outside of bottles removes excess heat and constantly works to lower bottle temps to outside 2/?
Glassman62
This removes some energy from air and as it decompresses leaving neck the air is cooler. Would be better if could use some water 3/4
Glassman62
Flowing over outside of bottles. Air going into house doesn’t get increased humidity but air temp drops further. Could use dirty water even.
Elephanthead
i think i saw a good gif here recently of a large clay(?) one in a city that had the added function of water and looked pretty neat.
DiracsDelta
Also an engineer. The conductive heat transfer you described is minimal. The cooling is from the Venturi effect as the air speeds up.
ourari
Not an engineer, so I have a question: What would be the best material to use in this design? I imagine a metal would increase performance?
DavidBrooker
You're describing this like it's a refrigeration cycle (compression, heat rejection, expansion), but I strongly suspect the process 1/2
Prebez
A staggering and impressive level of detail! Much appreciated!
jiynxed
yeah but then you gotta deal with getting the water flowing - this is a solution for areas where they barely have the power to run fans.
WhatWaresWouldAWerewordWear
Wouldn’t it stop cooling once the bottles reach air temp?
HaveImetyoubefore
Cool stuff! Thanks