Reynolds Number - Sixty Symbols

[xtremetom180]

love the video man

[SuperDogbrown]

really informative and interesting

[adisa091]

@Quintinohthree I took the course in fluid mechanics last semester and when calculating Reynold's no. we used Re = (rho x velocity x dia.)/mu. So, I guess that's why he uses radius here, because he is using kinematic viscosity and we used dynamic viscosity. Just realised that haha.

[MrP2409]

Not very interesting: fluids have viscosity. Fluids travel through a tube at a velocity. Flow rate is also dependent on tube diameter. At a certain velocity, turbulence ensues. Big f'n deal.

[adisa091]

Surely he meant Diameter, not radius?

[Quintinohthree]

@adisa091

How so? If you'd use the diameter you'd just get a number twice as big so you can do your calculations either way you'd just have to correct other formulas for this.

[EducationLover]

he professor Laurence Eaves.

[ratje67]

@ 1:05 "you can see this got a diameter" Such an obvious observation sounds enigmatic coming from a phisicist....I feel like I'm missing some clue here. LOL

[manalokos]

Is there any use for the Reynolds Number?

[signious]

@manalokos nearly any dynamic analysis on liquid flow

[mdiem]

Gah, engineering flashbacks!

[gcndavidmn]

Is the Prof Welsh? He sounds like my grandfather.

[InsanityCrescendo]

@gcndavidmn You have a cool grandpa

[miniskel]

What is the name of the professor?

[rockerlkj]

Anyone else think that the music in this video is eerie as hell?

[Streety101101]

i herd bananas are an excellent source of potassium....dose this mean girls will want to sleep with me now cause i know something?....

[martls6]

In the vulcano's case; which radius do they take to calculate the reynolds number?

[GRAHAMAUS]

I read somewhere that one reason early aircraft pioneers were held back is because model wind-tunnel tests of aerofoils didn't scale up as expected, because Reynold's Number wasn't taken into account (since it was discovered in 1880-something the information was there, just not widely known or realised to be relevant presumably). In part the success of the Wright Brothers was that they did apply this new knowledge and so their wind tunnel tests scaled up a lot better to the full-sized design.

[TheWOWXDWOW]

These videos realy help me to understand my physics leasons, Thank You!

[onehundredand37]

lol pulls out a pipe nears a desk

[ib9rt]

So physicists like to use the radius of a circular pipe for Re, huh? (Engineers like to use the diameter.) It seems even dimensionless numbers can suffer from "units of measure" problems when communicated from one person to another... :-(

[mdiem]

@ib9rt

Depends on if you are making the measurement with a ruler (or calipers) or a formula...

[marsCubed]

Where are the vortices without the flow?

It kind of defines nothing as vortices cancelling each other out. Add a direction & lovely big particle pairs come streaming out.

Ty for upload. makes one think.

[aayushkhanna]

AWESOME! :"D

[TheKitch2]

Doesn't fluid density play a role in the Reynolds number?

i.e Re=density*fluid speed*diameter/viscosity?

[Andrewinadoghat]

@TheKitch2 kinematic viscosity is viscosity/density, so yes fluid density plays a role.

[TheKitch2]

@Andrewinadoghat Ah right I didn't notice it was kinematic viscosity, thanks!

[ikbenharm]

lets try that on tornado's

[ikbenharm]

so for example the eye on jupiter could be annuled bu sending in a highenergy sunbeam in to the atmosphere in the correct point?!?! isnt it??

[hnaef83]

Wait -- Reynolds 'passed water' through the pipe? Eww!

[samwise811]

how can we prove that Reynolds stress is -p*u(i)*u(j) ???

[dcsnunes]

what is the link of the website the professor talks about in the video?

[G3org3Master]

So is this the reason for the swirling trails behind rockets from rocket launcher guns?

[Digikong]

It is the end result of a change of pressure and velocity within an air system. Reynold has more to do with what is going on inside or around the pipe or wing. Pipes in the house and pressure takes this into account to keep water quiet in the pipes.

[1HillbillyGirl]

If only my science teachers had been more like Professor Eaves and less like nodding versions of Ben Stein... sigh..

The Sixty Symbols team has made science FUN again!

[adityat90]

No disrespect to Osbourne Reynolds but the guy looks like Vincent Van Gogh.

[timdopte]

no dissing flandres painters.

[Digikong]

That is kind of disrespectful to all of us who do not look like Vincent Van Gogh. We are not known as Van Goghs for our works so perhaps our looks have something to do with our short comings? I doubt it we just need to think with different symbols.

[idntexst]

number 23 will get you.....bu ha ha lol

[imataxslave]

Useful for calculating drain pipe needed for runoff. This spring I saw a YT video of a road getting washed away from a drain pipe design fail. I'm thinking someone forgot about ole Reynolds...and many other things.

[nawitus]

I hate when people use the "x" symbol instead of "*" for multiplication, it always reminds me of cross product. I just don't know any reason for that. Or is the * symbol rare in British/American schools?

[nawitus]

By the way, wikipedia says the formula for Reynolds number uses diameter, not radius, but not sure which is the correct formula..

[hotdogtanner]

i would believe the actual physist than wikipedia

[017524062]

The "*" symbol for multiplication in never used in any American or British school as far as I am aware. The same applies

, I believe, to Australia, New Zealand, South Africa, Zimbabwe or any other former British Colony. I am from an English speaking country and I have a maths degree and I never use the "*" symbol!

[ilikebleach]

"*" symbol is the computer symbol for multiplication, when writing a computer program the normal multiplication symbol, "x", cannot be used because it would be registered as a letter of the alphabet.

[017524062]

I forgot to say that it is obvious that when you are dealing with vectors that the "X" means cross product and when you're dealing with scalar quantities it means simple multiplication.

[nawitus]

Well, "*" is superior in any case.

[singermike]

When I get a better webcam/digital cam I'm doing a video to raise money for charity. Please check my channel and video to be a part of it. When it happens I will need all the advertisement I can get from other viewers. Spread the word. Thanks.

[241Groundhog]

The number is not constant... so what's it good for ????

[feelgoodhitofsummer]

@241Groundhog : By calculating the Reynolds number you can determine whether the flow in for instance a tube is laminar or turbulent. This has all kinds of effects on mixture or temperature gradient of the flow. Which is quite important to for instance chemical engineers like myself...

[nymafia888]

so is 2012, dec 20....the End ? ...4 a funny shit laugh. Search F'n Singin Telegrams

[kingpopaul]

dec 21

[dubai2050]

he look freaky with that pipe.

[unhappy2cu]

interesting as fuck wow.

5/5

[Micieri]

physics is 99% history

PROVE ME WRONG

[Be3p123]

uh... what??

[stan007stan]

Why we should prove you that you are wrong? Chemistery, biology, etc... are made of history too. What is your problem?

[Porterjebazillanator]

Seriously, this is a video about fluid dynamics, not an argument forum for creationists and evolutionists to duke it out. If you really feel that compelled, go find someplace else to have your arguments and let everyone else enjoy the videos.

[Daruqe]

@Porterjebazillanator

"Duke it out" makes it sounds like they have equal footing.

[ravn87]

How is it you expect people to be considerate of your beliefs and theories, if you can't be considerate of theirs, regardless if you agree or not?

Whether it's befitting or so isn't the point. Great communication starts with congenial consideration in effort to bridge gaps and learn.

(s)he's fine, let them speak their mind.

For the record, Being a scientist who believes in God or higher entity isn't such a bad thing.

[0n3m4n4rm33]

viscosity should be represented as inertial dampening...

[0n3m4n4rm33]

Shut up woman. Pick up a book...

[Truthiness231]

Yes yes, because god would only stop sending his creations to eternal hellfire for every little thing if he could first see his son (which is him) die in front of him. We've all heard the stories...

[solomsolomol]

i hate to break this little conversation of yours , but creationists have no place in these videos ,so could you please go somewhere else ?

[AtheistPride007]

Hey god hates you.

[zero252627]

I thought atheists didn't believe in God?

[AtheistPride007]

I'm 100% sure that if there was a god IT WOULD HATE YOU.

[zero252627]

Haha well I'm 100% sure there is a God and he loves you.

[summerfunteam]

amen

[bethilyboo]

..... damn, I just lost the game.

[henrebotha]

DAMMIT.

[TheJapanChannelDcom]

Nice job blowing my mind!

5 stars from TheJapanChannel !

Check out our videos too if you have time!

[jeffwads]

I just came up with a "number" to describe my sex life...69. Yeah, it is almost dimensionless but it makes just as much sense as this stuff.

[solomsolomol]

this is exactly why i hate it when youtube spotlights their videos , stupid people who think they are funny come and start making lame jokes

[Keebus87]

I've got to take an exam about this and much more stuff right tomorrow! :(

[OhYeahMilkIt]

is this Rudy Giuliani?

[Twist9]

I love the photos and video, awesome.

[panchoxpanchox]

i dont like fluids :(

[Tryambakam]

that fun with flat fluid experiment is so trippy and psychedelic

[sporkafife]

I've heard that the vorticesat the tips of aeroplane wings are the reason they have the small vertical sections at the ends of some larger aircraft's wings... is that true??

[AnonEngineer]

Yes, the wing tip is usually a different shape in order to decrease the drag the wing encounters which is greatest at the wing tip.

[mundayP22]

the vortex forming at the wing tip has the same effect as shortening the wing. it is caused by the low speed air under the wing leaking into the high speed air above the wing. the wing tip fins help to throw this vortex further out off the actual wing surface and hence you gain lift and use less fuel.

[xja85mac]

Speaking viscosity, you may also consider Deborah number (named after prophetess Deborah, which singed, roughly, "everything flows in front of God"), it is a number which explains how much something is viscous and elastic.

For example the Deborah number tells us how much fast we have to go in order to ski on water, or how much slow you have to press in order to extrude a metal.

[Chipsonfire]

I hate the Reynolds number lol. But that's mainly because I'm not a fan of fluid mechanics in general. The only number I can think of that I hate more is the horrid Nusselt number :p Great vid though!

[AnonEngineer]

I can't agree with you more, Reynolds and Nusselt numbers - EVIL!

[5dArK5sOuL5]

This is greate!

[sixtysymbols]

We've uploaded this a second time with new pictures and a couple of corrections... sorry to inconvenience any subscribers!

[kaisaris25]

No problem! We're just glad you upload videos at all!

[2szymi]

and for free :P

[x246869]

1,000,000 versus 100,000 .  See, we do pay attention.

Great videos.