Stuff You Should Know - Wind Tunnels: More Important Than You Realize
Episode Date: October 13, 2020Without wind tunnels we may not have airplanes right now. Early aviationists built them to puzzle out how to get and stay airborne. But wind tunnels are used for so much more than flight – from micr...ochips to wind turbines. Enjoy this breezy episode. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.
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On the podcast, Hey Dude, the 90s called,
David Lasher and Christine Taylor,
stars of the cult classic show, Hey Dude,
bring you back to the days of slip dresses
and choker necklaces.
We're gonna use Hey Dude as our jumping off point,
but we are going to unpack and dive back
into the decade of the 90s.
We lived it, and now we're calling on all of our friends
to come back and relive it.
Listen to Hey Dude, the 90s called
on the iHeart radio app, Apple Podcasts,
or wherever you get your podcasts.
Hey, I'm Lance Bass, host of the new iHeart podcast,
Frosted Tips with Lance Bass.
Do you ever think to yourself, what advice would Lance Bass
and my favorite boy bands give me in this situation?
If you do, you've come to the right place
because I'm here to help.
And a different hot, sexy teen crush boy bander
each week to guide you through life.
Tell everybody, ya everybody, about my new podcast
and make sure to listen so we'll never, ever have to say.
Bye, bye, bye.
Listen to Frosted Tips with Lance Bass
on the iHeart radio app, Apple Podcasts,
or wherever you listen to podcasts.
Welcome to Step You Should Know,
a production of iHeart radios, How Stuff Works.
Hey, and welcome to the podcast.
I'm Josh Clark.
There's Charles W. Bryant.
There's Jerry Woosh Rowland over there.
He's just getting worse and worse.
This is stuff you should know.
Wind tunnel-a-dish.
Aren't you glad we're not in the same room
so that you couldn't smell my breath when I went out?
Yeah, my daughter's gotten a bad habit of doing that
and she thinks it's funny.
I'm like, it's really not.
Of what?
Of like, breathing in someone's nose on purpose,
like right in your face and like, no one likes that.
Yeah, she's just entered the age of what,
five to 55, where that's something people do?
Yeah, not funny ever.
I'll tell you what, these masks that we're all wearing,
that's a real reckoning with your breath though, isn't it?
Oh my God.
It's funny.
It's like an hour by hour slide into despair.
You're like, I don't remember eating garlic.
Yeah, it's like in the morning,
it's like, oh man, this is great.
I love this mask.
And later in the day, you need that toothbrush.
Yes, it's true.
They say you can't smell your own breath
and they are wrong.
And I'm brushing my teeth now more than ever
because I'm scared to go to the dentist.
Yeah, same here.
I'm also flossing like a mad person too.
You're flossing right now, I can hear it.
Wow, that was the most PC thing I've ever said.
Is what?
I'm flossing like a mad person, not a mad man.
And technically, I guess not.
I would have said like a mentally ill health person.
Yeah, I think that's even bad.
Who knows these days, right?
That's right, let's talk about wind tunnels.
Okay, so we're talking wind tunnels.
And I had no idea how interesting wind tunnels were.
I had an inkling that they were going to,
that there was like more to wind tunnels
than people realize, which is absolutely true.
But they're a deep cut.
Yeah, I mean, there's way more to them
and you can do way more with them
and learn way more from them than I thought
because my experience with wind tunnels,
like most people is seeing the cool TV commercial
with the like green smoke flying over the car
to demonstrate how aerodynamic it is.
And to be sure that is a very big part
of what they use wind tunnels for.
Yeah, yeah, and Chuck, you know,
you and I were in a commercial in a wind tunnel.
I thought you might bring this up.
That was a wind tunnel, technically.
That indoor skydiving thing is a type of wind tunnel.
It's a vertical wind tunnel.
Yeah, if you guys haven't seen that,
it's been a while since we promoted these things.
We used to do these little shorts.
No, this was different.
Well, no, but these were based on those shorts.
Oh, sure, sure, yes, yes.
Yeah, we did these little shorts
that we called interstitials.
Did a lot of them and to me,
it's like the best video work we've ever done as a team.
I'd love don't be done, but that was just you.
Oh, go on.
Well, it was great.
It was you in a room and it was this chair
and you sort of played a character.
Yes, go on.
And some people had problems with the character
because they thought you were making fun
of a certain kind of person.
Yes, sure, sure.
But that wasn't true.
It was all very kindhearted and just funny.
That's right.
That was really great, thank you.
Sure, and that chair's still here in the office, right?
Yes, it is, and I believe my outfit still is.
I'm waiting for the Smithsonian to call.
So yeah, we did this TV commercial for Toyota
that was very much in the vein of those interstitials
where we were in just all over Atlanta
in various parts of Atlanta doing funny things.
That was L.A., remember?
Well, no, again, talking about the original interstitials.
Oh my God, I'm so confused.
Then when we went to L.A., we did the same thing.
We replicated that style in Los Angeles
and the upshot of this all is we end up
in a indoor skydiving facility having a conversation
like a normal conversation or trying to.
That was the gig, the gig, that was the gag.
That was the bit.
Really, yeah.
And you get slung against the side of it at the end,
which is kind of the funniest part.
Yeah, it really was.
It was supposed to be an outtake
and they made it an intake for sure.
Those things were very difficult to,
if you've never done one before,
I mean, it was fun and kind of cool, but it's not easy.
You don't just go in there and be like, hey, I'm floating.
No, it's really, really hard actually.
Yeah, like you're working every muscle in your body.
It's kind of like water skiing looks fun too.
Yeah, you were good at it.
I was not very good at it.
I was okay, but it was tough.
Yeah, so that was what would be technically
called a vertical wind tunnel, right?
And they actually use those to research spin.
Like when something goes in like a tail spin
or like a helicopter goes in a tail spin,
they would use a vertical wind tunnel
to test for that kind of thing.
Right, but the wind tunnels we kind of more think of
are the horizontal tubes where you see a car
or something like that having the cool smoke blown over it
for a commercial, but they're very useful.
And this is something I didn't really know.
I kind of just thought they were all these big giant things
that you would put an actual car in.
Most wind tunnels are these little desktop models
that you use in a science lab that have a scale model
that you're using instead of the actual thing.
Right, which means, yeah, that you're using
a smaller version, but that is precisely scaled down.
It's not like, it's roughly the right size.
It looks the right size, doesn't it?
Quit your complaint.
I'm sure this plane will fly, this is close enough.
But what's neat about that is that they can scale
this thing down, they can subject it to the same conditions
as they would a full size model,
but then they can correct for the data,
whatever the numbers they're getting, the output,
they can correct to scale it back upwards, just using math.
Because if there's one thing that goes hand in hand
with wind tunnels, it is math, friends,
because the whole point of wind tunnels
is to study aerodynamics, which is the flow of air
or gas is over an object, and in this case,
it's a stationary object and the wind is moving,
but what they're really doing is simulating
that object moving out there in the real world into wind.
And I mean, that's a wind tunnel.
And when you put it like that, it sounds very simple.
They are not simple at all.
There's really nothing about wind tunnels that's simple,
from their construction, to their cost,
to what they're used for, to all of the different variables
and conditions that they can test for there.
They grew in step, hand in hand with the aviation industry.
Like we probably wouldn't have an aviation industry
right now without wind tunnels.
And that should kind of give you an idea
of how complex the stuff that people are doing
in wind tunnels is, or the data they're extracting
from these wind tunnels tests.
It's not just like, look that cool green smoke
bending over the car.
That's for yokels like you and I watching ads
while in between golf.
Right.
You know, like you're watching golf and the ad comes on.
Sure.
My brain.
It's the best part of golf.
The ads.
I've actually kind of gotten.
Are you watching golf now?
Yeah, kind of here or there.
It's not something I seek out,
but and it's not for the golf.
I could care less about the golf.
It's the views, it's the shots.
The golf courses are just,
they have the most amazing backdrops.
And it's just so tranquil and calm.
It's really something.
Yeah.
You know, I live right down the street
from the legendary Eastlake country club in Atlanta
and Bobby Jones course.
And I've been to one day of that one tournament.
That's the only time I've actually been
to a professional golf tournament.
And you know, I stood there 12 feet from Tiger Woods
in the tee box.
It's pretty, pretty neat.
Wow.
Like just to see, cause I played golf a lot growing up
and it's a hard sport.
Yeah, it really is.
And to see someone do it perfectly,
right in front of your face,
with that much power, it was really impressive.
You know what would really help Tiger Woods swing?
If they put him in a wind tunnel,
put some green smoke in the wind and watched him swing,
they could tell him how to do it better.
You want smoke?
I'll give him smoke.
That's right.
That's right.
Shout out to our Detroit crew from back in the day.
All right.
So if you want to go back in time
and talk about human flight,
you're going to look at things like Da Vinci's
Ornithopter in 1485
and kind of a lot of early stabs at flying
where humans looking at birds and thinking,
well, if we're going to fly,
we're going to have to learn how to flap wings really fast.
Yeah.
And it made sense, I guess.
If you're looking at birds,
they're the only thing flying around.
It would make sense that that's where they would go,
but they knew early on, regardless of the flapping,
that they needed to understand wind
and how wind worked with wings.
And so they started going to these little hills
and mountains and they started going to caves
that had this, you know,
they were looking for some sort of predictable,
constant wind so they could do some early testing.
And they realized you just can't do it with mother nature.
You can't get a consistent wind,
not enough to get real data out of it.
And then do that math that we need so drastically
to make this possible.
Right.
So, and initially we got that assist from birds
in that we knew wings had to be involved.
Gotta have wings.
The whole flapping thing really kind of threw things off
for a while, but because we knew that there had to be wings,
we knew that there had to probably be some ideal
or optimum shape of wings.
And that's really where wind tunnels first got their start
was in testing different shapes of wings or airfoils.
And there was a guy back in 1746 named Benjamin Robbins
who created a Worley arm,
which is basically like a,
it was a centrifuge basically is what he created.
Yeah, I had a hard time picturing this
and there's only, there's this one very rudimentary sketch
that made it even more confusing.
Okay, so just imagine you have like a pole
coming out of the ground vertically
and you have an arm attached to that pole
and the pole can spin around in a circle,
like a centrifuge, like one of those G force testers
that they have it and like astronaut training.
You know what I'm saying?
It goes around really fast.
Yeah, yeah, yeah.
That thing, this is what that guy invented,
but it was like with wood in the dirt.
It was, and it didn't go that fast,
but you could have fixed a like a wing type
that you were testing to see if it worked well
to the end of it and push it through the air.
And it didn't really help this guy figure out
what wing style or size was the best.
What it helped him figure out is that
it doesn't have that much to do with anything with flapping.
We don't need to be wasting our time
inventing machines that flap their wings
because that's not it.
It's all about this thing called lift and drag
and the proportion between those two.
And if you can figure out how to get more lift
and decrease drag, then you can really make some,
you can fly basically.
And this was the very first inklings of that
that Benjamin Robbins came up with.
Yeah, and what I saw was that Robbins
really kind of pinpointed drag,
like the shape is super important.
And then after him, Sir George Kaley
had his own whirling arm and he's the one
that really figured out lift was a key
after they realized the shape of the thing matters.
The more than the shape, like the size of it matters.
Size does matter.
Especially when you're flying.
Especially when you're flying.
And that if you could just get a quick enough takeoff,
you don't need to flap at all.
All you need is a lot of speed at first,
which they could have also gotten, frankly,
by if they would have kept looking at birds
and realized they eventually stopped flapping.
They might have realized,
oh, you actually don't need to flap the whole time.
You can glide if you've got enough speed.
Right, and well, actually a lot of the early
flying machines were gliders.
It was the Wright brothers were not the first people
to engage in human flight.
There is a monk named Elmer of Malmsbury,
who has the first recorded human flight back in 1050 CE,
not BCE.
And he, you know, that was almost a thousand years
before the Wright brothers,
but the Wright brothers are credited
with like an engine powered flight, human flight, right?
So they were dabbling in what Kaylee and Robbins,
well, Kaylee especially had figured out that you need thrust
and there's just nothing around that's light enough
to produce enough thrust.
So Kaylee actually gave up and went
and joined parliament for a while
before he finally created a flying machine,
50 years before the Wright brothers.
What a loser.
He made his coach driver, test pilot it.
And the coach driver was so scared,
even though the flight was successful,
that when he landed, he was like, I quit, I quit.
I'm not, I don't work for you anymore.
Wow.
Yeah, but George Kaylee's very much overlooked figure
in the history of flight.
He apparently figured out the general shape
of a modern airliner back in 1799.
Crazy.
Yeah.
All right, I say we take a break.
Okay.
We'll come back and talk about the first wind tunnel
right after this.
On the podcast, Hey Dude, the 90s called David Lasher
and Christine Taylor, stars of the cult classic show, Hey Dude,
bring you back to the days of slip dresses
and choker necklaces.
We're going to use Hey Dude as our jumping off point,
but we are going to unpack and dive back
into the decade of the 90s.
We lived it, and now we're calling on all of our friends
to come back and relive it.
It's a podcast packed with interviews,
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to the best decade ever.
Do you remember going to Blockbuster?
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Do you remember getting frosted tips?
Was that a cereal?
No, it was hair.
Do you remember AOL Instant Messenger
and the dial-up sound like poltergeist?
So leave a code on your best friend's beeper,
because you'll want to be there
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Each episode will rival the feeling of taking out
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as we take you back to the 90s.
Listen to Hey Dude, the 90s,
called on the iHeart radio app,
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Hey, I'm Lance Bass, host of the new iHeart podcast,
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Um, hey, that's me.
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All right, so Kaylee has these whirling arms going.
Terrible name, but it worked out.
Sure.
Then enter a man named Frank H. Winham.
He was another Englishman, and he was
in the Aeronautical Society of Great Britain.
And he said, guys, we need, or excuse me, gentlemen,
we need a wind tunnel, and we need it bad.
And so in 1871, he had a, the very first wind tunnel.
It was 12 feet long, about 18 inches square,
with a 40 mile an hour wind, which is pretty good.
It was, it consisted of your daughter going,
oh God, stinky as wind tunnel.
Her breath isn't that stinky yet.
Kids don't really start to stink until later, I think.
Yeah, until later.
But the winds were powered by a steam fan
at the end of the tunnel, and it worked pretty well.
He was able to get that leading edge of the airfoil
and move it up and down, and change his angle of attack,
and kind of see what shaped and what angles worked best
with to get the best lift.
But it was still sort of choppy,
and it was rough around the edges.
And if you really want to make this,
if you want to fly safely,
you got to have a really, really, really consistent,
very smooth wind to work with to get that data.
And they still didn't have one at this point.
No, they still didn't, but they were advancing
by leaps and bounds here,
that people were building their own wind tunnels,
because up to that point,
if you had a design for an airfoil,
for like a wing size or shape,
you had to build it and then go take it out into nature
and test it and hope for the best.
And it was really expensive, really time-consuming.
With your own wind tunnel,
you could make a model of the shape and test it out yourself,
and then see, oh, this is actually worth pursuing,
or this is junk.
And that's what our dear beloved heroes,
the Wright brothers did in Ohio,
outside of Dayton.
Orville and Wilbur Wright built their own wind tunnel.
These guys were just like tinkerers.
They owned a bike shop,
but they were so fascinated
and were following these developments in early flight
that they just kind of got into it themselves.
And they built themselves a wind tunnel.
They had like 200 different types of wings, I believe,
that they messed with,
selected the 30 best ones
that they had developed in their wind tunnel
of their own construction and design.
And apparently, I saw somewhere that by 1901,
after their wind tunnel tests,
the Wright brothers,
couple of bicycle repairmen in Dayton
had the world's most accurate data,
scientific data on flying and wings in the world,
and they'd come up with it entirely by themselves.
Yeah, and here's the thing with these wind tunnels,
especially early on, and kind of still,
it's not like they could use that wind tunnel
and come out with a surefire product using math
and testing different designs and shapes and tilts and angles,
but it was such a time saver and broken bone saver
that you didn't just say,
all right, well, I think this might work,
let's go and push our cousin off of a cliff
or our coach driver or whatever and see if it works.
They still had their failures, all of them did,
but I mean, it would have taken,
I mean, God knows how many more years
if they didn't like at least start
from a point of likely success, thanks to wind tunnels.
But I mean, like, look at it,
they finished their wind tunnel tests in 1901,
they had their first powered flight in 1903.
Yeah, I mean, that's amazing, two years.
And it definitely did accelerate it too.
And so you can see from the outset
that aviation and wind tunnels just developed together
and wind tunnels developed aviation.
But the first wind tunnels, like you said,
they had a really big problem.
And that was the air that they produced,
the stream of wind was very choppy, very turbulent.
And your data was not necessarily reliable.
It wasn't too terribly much better than, say,
going out into Mother Nature and subjecting, you know,
the same model to those winds.
And that's a big problem.
So one of the first things that they figured out
how to do was to make the wind smoother
so that you could get a reliable, smooth, steady wind
in your wind tunnel whenever you wanted to use it.
Yeah, and that's where we come to the modern tunnel,
very, very smooth airflow.
And they have five basic sections of,
and they're all different,
but they have five basic sections in a modern tunnel.
That's the settling chamber, the contraction cone,
the test section, the diffuser and the drive section.
So we start out with this swirling air
and it's a big choppy mess
and it enters the tunnel.
And we'll talk about how in a second
because it's kind of cool, little counterintuitive,
but it makes a lot of sense.
It goes into the settling chamber,
which does exactly what you think.
It settles that air, straightens it out.
They might have these little honeycomb holes
or a screen or these panels.
And that's just sort of the initial thing
to sort of get it nice and smooth.
And moving in the same uniform direction.
Yeah, and then it goes down,
they step it down through that contraction cone.
And that just, I mean, it's like anything else.
If you make the tube smaller,
it's gonna increase that velocity of air flow.
And that's where it gets to the test section,
which is whatever.
And the test section depends on what you're testing.
If it's a desktop thing,
the test section might be 12 inches long
and you might have a tiny little model
of an airplane wing in there.
And that's where the actual thing you're testing is
where all the sensors are recording all the data
because you've got your visual,
you've got these windows so you can shoot TV commercials
and you can look at the thing.
But there's also all manner of sensors
to pick up on all manner of data and observations.
Yeah, I think that's really cool that they still,
when they operate wind tunnels,
they still watch through the window
because there is a lot to be gained visually
from just human beings watching this stuff.
And it's cool, you wanna watch it.
Right, yeah, for sure.
Especially when they got the green smoke thing turned on.
Oh, absolutely.
So after it goes through the test section,
it enters a diffuser which kind of,
it slows things down and maybe just exits the whole thing.
It's kind of the opposite of the contractor,
it just opens back up.
Right, exactly.
So there's, as far as breaking,
there's a lot of different kinds of wind tunnels as we'll see.
But there's really kind of two categories,
two broad categories.
You've got open and closed circuit.
And an open circuit is where you have wind going in
on one end, going through the diffuser and the honeycomb
and the test section and then coming out the other end,
blowing into the room.
And another, with the closed circuit,
it's just basically an oval.
And so when the wind is generated,
it goes through the test section out the back,
but then bends around an oval track
and then comes back around again
and through the contraction cone and into the test section
again and again and can just keep going
rather than just blowing out the other side.
Yeah, and here's the part that I said wasn't intuitive,
but it's really kind of neat when you think about it.
The drive section is where this fan is.
And this is what is just generating that airflow.
And I always just thought a wind tunnel
was a fan pointing at the thing.
Right.
They're actually behind the thing.
Yeah.
Because you don't wanna push air onto something.
You want air being pulled over something.
And it just makes total sense,
but you never really thought about it.
You just, I always just pictured a big fan blowing at a car.
Right.
But the fan would actually be behind the car
and it's probably looping around
and smoothing out this entire way
and then being gently pulled over the car.
Exactly.
In just the same way that the fastest way to cool off,
say like a server room that you don't have good cooling on,
you just throw a box fan the opposite way.
So the box fan is blowing out into the regular room,
but at the same time it's sucking the air,
the hot air out of the server room.
And cool air is rushing in to replace that hot air.
So you're creating like an airflow
that's much less turbulent.
When the fan sucks the air out,
it's much smoother than when it blows it in,
which creates a lot more turbulence.
And that was the big problem that was facing
like the Wright brothers and some of those other
early wind tunnel creators is they,
their fans were blowing on the front of their models
rather than having the fan behind it
sucking the air over the models.
Right.
So these little models, they're kept in place.
Sometimes they're on wire,
sometimes they're on these metal poles.
Sometimes I think the really super high tech ones
use super strong magnets to actually hold them in place,
which is pretty cool.
And then again, you've got all these sensors
all over the place attached to the model measuring.
I mean, we'll see, it gets really, really deep,
but just at the outset you can measure like wind velocity
and air pressure and temperature.
And if you're talking about airplanes,
roll and yaw and drag and lift.
And I mean, you can kind of do anything you want in there.
And if you have, like if you're testing an airplane
or a scale model of the airplane you're gonna build,
it's on something called the Sting,
which is a pole basically that goes into the airplane's
bottom, but, but then inside the airplane,
the airplane's not attached to the pole,
it's attached to something called a balance.
And it's like all those sensors you just mentioned
all in one instrument, like a cylinder or tube.
And as the airplane moves and pitches and yaws and rolls
and gallops and all that stuff, not gallops,
though I made that part up.
It's acting on those sensors and the motion,
the mechanical motion on those sensors is translated
into an electrical impulse and that travels down
the stinger into the computers which are picking up
all this data in real time and logging it
and creating new versions of the model based on that stuff.
It's pretty amazing.
What's even more amazing, that makes sense
that that exists today.
That's existed since like the 40s or the 50s
in much more primitive form,
but essentially the same thing that we use today,
the same kind of balance, what has been around for decades.
Wasn't there a Simpsons joke about yaw control?
Yes.
Yeah, when they had one of those like backyard rockets.
Oh, right.
Now with yaw control.
It didn't like buzz Aldrin or something.
So you're like, wow, look at that yaw control.
Yeah, I think so.
That was good stuff.
It was good.
Some other things that they measure,
which you might not really think about existing,
is viscosity and compressibility.
This is huge.
Or the tackiness or the bounciness of the air itself.
So when you're thinking about air blowing over a car,
driving down the road,
you don't think of that air as being sticky necessarily,
but when that air is moving over the hood of that car
and the top of that car or the plane or whatever it is,
those little molecules are gonna hit the surface
and just very, very briefly,
they're gonna cling to that surface
and even for that brief, brief amount of time,
it's gonna create a little boundary layer of air
next to the thing that you're trying to measure air flow over.
Yeah, which is like I said, a very big deal.
And yeah, an individual air molecule
is going to stick for a nanosecond,
just some ridiculously short amount of time,
but there's so many air molecules
that they essentially just replace each other
as fast as they can move.
And yes, they create this boundary layer.
And as far as aerodynamics is concerned,
your say your car, like driving through this wind
that's sticking to it, now has a different shape.
That boundary layer creates a different shape
or extends it outward beyond the actual physical shape
of the car.
And so when you-
Even a tiny amount matters.
Yes, very much so.
And then so when you're trying to test
like how fast the car is gonna go,
how many miles per gallon it's going to get,
that kind of stuff,
that boundary layer makes a tremendous amount of difference
because it changes, physically changes the shape
of this thing when it's out there traveling at high speeds.
So one of the great benefits of an air tunnel
is you can test like what boundary layer is produced
by this particular shape of this car under this condition.
You know, if it's 90% humidity,
but you know, 40 degrees Fahrenheit
and they're traveling at 80 miles an hour,
what kind of boundary layer is produced?
Okay, well, what about 75 miles an hour at 60% humidity?
You can just change all these variables
and the wind tunnel allows you to simulate it
and basically get all this data in real time.
Just lickety-split basically.
Although one other thing, I just wanna say this,
we're making it sound like this is fast.
This is actually, and has been,
and especially until the age of computers,
very arduous work because if you wanted to change
one variable, if you said, well,
this headlight is actually causing way too much drag,
you would have to switch that headlight out
with your next model and run the same tests
over and over and over again
with the different conditions and log all that data.
So it was really arduous before computers
and you kind of get the idea that aerodynamics
as a field of study is really given over to computation.
Like there has been a huge savior for that field
and helped it along and saved a lot of people a lot of time.
Yeah, and you mentioned things like humidity and temperature.
They're all different kinds of wind tunnels
and they can be very specific as to what they want to test
or very broad, but they're all able to do things like that.
You can dial in a temperature.
You can dial in atmospheric pressure
if you wanna see what something's like on Mars,
which they have to do if you want the Mars rover
to be successful.
They can ice up a plane wing
just by introducing a refrigerated air
and spraying a mist of water
that freezes and lands on the wing.
And you can simulate all these different things,
humidity and temperature,
and it's just amazing that they thought to introduce,
at first they started out probably just looking
at aerodynamics of flow over a thing,
but as they got more and more specific with their needs,
they just said,
we can design these tunnels to kind of do
anything we wanna do.
Like recreate any environment you can think of basically.
Yeah, it's true.
And I mean, like as we started to build planes
that go faster and faster,
we started building tunnels that simulated
that really high speed travel.
And so we have hypersonic and supersonic wind tunnels
that don't use fans at all,
but they use like bursts of compressed air
that blow right onto the model.
Yeah, those do blow at the thing
instead of sucking behind it.
Right, but it's a huge release of air
that is traveling so fast.
It simulates, like a jet flying through hundreds
or millions of miles an hour probably.
Yeah, or hey, what's it like for a rocket human capsule
to come back into Earth's atmosphere and not burn up?
Like they can simulate those temperatures.
Yeah, there's one in I think North Carolina.
No, University of Texas at Arlington
has something that can simulate that.
Goes up to 8,500 degrees Fahrenheit.
It's crazy, man.
It is, it's a wind tunnel.
For all intents and purposes, it's a wind tunnel,
but they have built these things
so that they can simulate basically any climate.
And we talked about smoke
and it's always fun in those TV commercials
to see the smoke blowing over the thing.
And it's a nice visual to sell cars
that look super aerodynamic
and are super aerodynamic.
But that visible flow isn't just for the stoners
in the lab department late at night to play around with,
although they probably do that.
But they, flow visualization is a real technique.
You might just have colored smoke.
You might have liquid, like a mist of liquid.
You might have, they use this colored oil sometimes
that you can see the wind pushing the oil
along the surface of whatever model you're using.
And then they've got these high speed cameras
capturing all of it.
And again, it's just, it's another variable
they can actually look at
rather than just using numbers and data.
Yeah, I saw one, one was taking photographs
at like 200,000 frames per second.
That's how high speed it was.
But it was, they were testing like a rocket
or something or a model of it.
Should we take a break?
Yeah, let's.
All right, we'll be right back
with more on wind tunnels right after this.
We're gonna use Hey Dude as our jumping off point,
but we are going to unpack and dive back
into the decade of the 90s.
We lived it, and now we're calling on all of our friends
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It's a podcast packed with interviews,
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to the best decade ever.
Do you remember going to Blockbuster?
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Do you remember getting Frosted Tips?
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Hey, I'm Lance Bass, host of the new iHeart podcast,
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I'm Mangesh Atikular and to be honest,
I don't believe in astrology,
but from the moment I was born,
it's been a part of my life.
In India, it's like smoking.
You might not smoke,
but you're gonna get secondhand astrology.
And lately, I've been wondering if the universe
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Tantric curses, Major League Baseball teams,
canceled marriages, K-pop.
But just when I thought I had a handle on this sweet
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my whole world came crashing down.
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And my whole view on astrology, it changed.
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Listen to Skyline Drive and the iHeart Radio App,
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So Chuck, I was like, a lot of this really breaks my brain.
It's one of those things where like,
oh yeah, I totally get this on the surface.
Let me scratch a little deeper.
I don't understand this at all.
And the reason why is because, you know,
aerodynamics requires a lot of math
and it's not just about the physics.
It's about the physics.
And it's not just about the physics.
It's about the physics.
It's about the physics.
It requires a lot of math and formulae
and all sorts of calculations that I'm not...
But you're great at that.
I'm not currently capable of doing that.
But one of the things that I tried to shake down was,
when you do a scale model of something,
do you have to scale down the conditions?
And it turns out,
I wasn't the first one to think about this.
Other people have,
including people who work in wind tunnels.
And apparently they do not do that.
They will say subjected to the same wind speed
as they would like the full size one.
But then they go back and use math to adjust
these, all the different variables.
And again, you know, we talked about pitch,
and yaw, roll, drag, lift, all sorts of stuff.
I'm sure quite a few things and variables
that you and I haven't even come up with
or run across during our research.
But in each one of these interacts with each other thing, right?
So it's like one of those things where,
you know, you have 11 possible toppings for a pizza
and that creates 12 million potential combinations.
It's a brain breaking amount of math involved.
Exactly.
So that's what they're doing to scale it down
and scale it up.
They can say, oh, well, it produced this data.
If we run it through these, you know, formula,
like we can show that actually,
like it will have this effect in the real world.
They're using that level of math.
Anybody who can do that with math, I admire them deeply.
If you're listening out there
and you can do stuff like that with math,
my hat is off to you because I will never be able to do that
and I admire you.
Yeah, and you know what?
We've taken some heat for kind of beating up on math
a little bit is like, oh, boring
because we were English and journalism guys
and history guys, but I've really come to appreciate math
and doing this show.
I'm no better at it and don't care to be.
But I appreciate the, you know, math is the one thing
that doesn't care about what you think about it.
It doesn't care about opinions
and there's no interpretation or nuance.
It's just math.
And like what makes, like to look at these,
to look at a math equation that would take a model
of an airplane and a tiny little thing
and a tiny wind tunnel and then say,
well, now we just scale it up to this
and this is how you do it.
Right, just multiply by 10.
It makes me so nervous, but a real mathematician
would be like, this is the last thing
you should ever be nervous about
because it's just math, it's just right there.
Well, it's just, and they probably,
the idea of doing public speaking
would probably scare the bejesus out.
And the thing is, like different things attract
different people and that's great
because that makes the world a lot more rich
and complex that you have all these different people.
If everyone was into math, it'd be a pretty boring place.
Or if everybody hated math, it'd be a pretty boring place too.
Like you need all different kinds.
Different strokes for different folks
makes the world go round I think is the rest of it.
All right, let's talk about some of these
wind tunnels in the world because they're amazing.
NASA has one at Ames Research Center in San Jose
or near San Jose.
Biggest in the world.
Biggest one, 180 feet tall, dude.
1400 feet long.
And the test section on this thing is 80 feet tall
and 120 feet wide.
So you can put a full size jet plane in that thing.
Yeah, I saw that.
I was like, well, what kind?
And they said 737.
Yeah.
And that's pretty good size.
That kind, buddy.
Pretty good size.
Yeah, that's a, I don't know if they call it this
but I hear henceforth call it the Big Mamma Jam.
Yeah, it uses six four story high fans,
each of which is powered by six 22,500 horsepower motors.
Six fans, each is tall as a four story building.
That man, that's amazing.
115 mile an hour winds is where it tops out.
Yeah, which is pretty great that there's also a lot.
Apparently, I was reading one, some like blog posts,
I think on like a formula one site.
And they were talking about how like every single company,
every single racing team has in its facility
a full size wind tunnel.
Like it can hold a full size formula one car
at the cost of like 60 to $100 million or whatever.
But they are like cutting edge
as far as aerodynamic study is concerned.
And the reason why is because like,
if you can shave a second off of somebody's time
just by reconfiguring,
the engineers reconfiguring the shape of a fin
or a tail or something like that.
That's, you just, it just paid for itself basically
because it may have just won like the, you know, the $1,500.
They won, okay.
Good job.
Yeah, thank you.
So there are NASCARs, obviously got a couple of these things
in North Carolina, the home of NASCAR, Aroden wind tunnel.
That is in North Carolina and it tests full size stock cars.
There's another one called Windshear there.
This is a closed circuit tunnel
that actually has a treadmill in it for cars.
It's got a built in rolling road.
Yeah, we saw that in a few places.
Like BMW has one with the rolling road.
You know what's interesting to me too
is so we saw that the aviation industry
and wind tunnels kind of grew hand in hand.
The auto industry didn't really look up wind tunnels
until about the 50s is when they really started running
their cars through those kind of places.
And they went, boy, these cars are not aerodynamic.
No, look at it.
Look at that yaw control though.
Yeah, I love those old cars though.
My old Plymouth Valiant that I used to have.
Yeah.
This is obviously way before anyone ever thought
of anything like anti-lock brakes.
And one of the most fun things I would do
when I was driving with friends on an empty road late at night
was get up to about 50 miles an hour
and just slam on the brakes.
Jesus.
It was so much fun, man.
It was great.
You would just go,
you would slide about 100 feet
before finally coming to a rest.
That was a great impression of slamming on the brakes too,
by the way.
It was good.
And you know, it was like, we called it the sled
because it was just this big, heavy hunk of metal.
It's not like I was sliding all over the road.
I was just sliding very straight in a line.
What's the opposite of aerodynamic?
That Plymouth Valiant.
There you go.
Sluggish, like a wet sponge.
Yeah, that's about right.
So, I think we should wrap this up
on the future of wind tunnels
because people have been saying,
like, well, wind tunnels are dead now.
We've got computational fluid dynamics,
which is basically computers can figure all this out.
If you put a shape into, you know, AutoCAD
and say, computer, figure out what, you know,
will happen if I try to fly this under these conditions,
it'll tell you.
And people have said, well, you know,
it takes a lot of work and a lot of money
to run and build and use wind tunnels.
So I think they're probably going away.
People who work in wind tunnels say, no,
do not do away with the wind tunnels, we need them still.
Because, yes, computation helps a lot with the early work,
but when you finally have something
that you need to prove,
you really kind of want to see it in real life.
You want to see that smoke.
To make sure, yeah, you want to see that smoke yourself.
And, you know, computer simulations
can't simulate green smoke very well.
You got to see that in real life.
So they're saying that this is complementary technology
and that they really,
we need to keep our wind tunnels around
because we still need them.
Yeah, and I think we'd also be remiss
if we didn't say it's not just vehicles
and seeing how like a space shuttle
or a car or a plane or a dune buggy
might run in the wind.
If you want to see how air flow affects
like a computer and components in a computer,
you can do that.
Good point.
Like how they cool computer chips.
If you want to figure out the very best design
for a wind turbine or a wind farm,
then you can use air tunnels.
There are lots of other different uses
that you don't think about
just on kind of everyday products sometimes.
Yeah, there's a, I have to say, there's a Virginia Tech.
There's an anechoic, I believe wind tunnel
where they test wind turbines
to see what kind of noise they're going to make.
And they have, so the walls are,
as far as the wind is concerned, it has four walls,
but as far as sound is concerned, it has three
because one of the walls is made of Kevlar.
So wind won't go through it,
but sound will go right through it
like it's not even there.
So they can take accurate measurements
of what's going to happen when the wind hits this turbine.
What kind of sound is it going to make?
And they're making the country folk
who live among wind turbines much happier.
That's awesome.
Yeah.
So that's it for wind tunnels, everybody.
There's probably more to it,
but it's far, far beyond Chuck's or my grasp.
So again, hats off to all the aerodynamicists
in all of their maths.
Agreed.
If you want to know more about wind tunnels,
go check stuff out on the internet.
I hear there's a man with the page boy haircut
who does a pretty mean demonstration.
No.
No?
No, that's just the printing press.
Oh, okay.
I thought he was a factotum.
He might be.
A Renaissance man.
Well, since I said Renaissance man,
everybody, it's time for Listener Mail.
I'm going to call this on wetlands.
And this is one from Brian from Queens.
And this is very cool.
I didn't realize this.
There was a music venue in New York
when I used to live up in New Jersey called Wetlands
that I would go to.
And I never knew there was kind of a cool story behind it.
And now I do.
So this is from Brian.
And he says, you know, the New York City area
surrounded by salt marshes.
And there are tons of ordinances protecting
New York City's natural flood and pollution guards
as you describe them.
In the 90s and throughout the 80s and 90s
at the Wetlands Preserve,
it was an activist nightclub named for the land
that Lower Manhattan was built on.
The club was on Hudson in Tribeca,
very much downtown Manhattan,
which back in the early settlement by the Dutch
was a subsequent takeover by the English
was all salt marshes.
The Wetlands Preserve colloquially referred to
as the Wetlands was open from 89 to 2001.
Dual purpose was to create an earth-conscious
intimate nightclub that would nurture live music
integrated with a full-time environmental
and social justice activist center
in the club's basement.
Wait, what was the years that was open?
89 to 2001.
There is a 100% chance that Jewel played there.
He doesn't list Jewel, but I bet she did.
Okay, well, he lists some people there.
He lists a few, but he also links to many more,
and she's probably in there.
Okay.
I think I saw Ween there if I'm not mistaken.
Oh, cool.
But he said downstairs activist plan, protests,
made pamphlets, wrote letters to politicians and lobbies,
generated boycotts, and educated club patrons.
While upstairs, we hosted,
or they hosted some formative performances
for legendary rock bands like Pearl Jam,
Dave Matthews, Maroon 5, Oasis, Widespread Panic.
And let's not forget Jewel.
Fish, Rise Against, Fishbone, Bikini Kill, Blind Melon,
and Jewel.
Yes.
The nightclub raised revenue for the activism center's
effort, efforts in the, in turn, the activism center staff
and volunteers educated nightclub patrons
on environmental, social justice, and animal rights issues
through posters, educational displays, literature,
et cetera, and film screenings.
The New York-based Wetlands Activism Collective
continues, the club is shut down,
but they continue its environmental, social,
and political activism to this day.
And that is from Brian Stollery.
Nice, Brian, that's pretty great.
Never knew that.
I think I went to a couple of shows at Wetlands.
Oh, you did.
And I never knew that there was something else
going on there, and I kind of had forgotten about it.
I wonder if when you show up, they're like,
he's a cop's cop, don't call him, it's in the basement.
Narc.
That was Brian, you said?
Yeah, Brian Stollery.
That's pretty cool.
Thanks for filling in the blanks for us.
They're Brian.
And if you want to be like Brian
and fill in some blanks for us,
you can send us an email.
Send it off to stuffpodcasts.ihartradio.com.
Stuff You Should Know is a production
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to your favorite shows.
How To Make A Fancy Living
with David Lasher and Christine Taylor
on the podcast, Hey Dude, the 90s, called David Lasher
and Christine Taylor, stars of the cult classic show,
Hey Dude, bring you back to the days of slip dresses
and choker necklaces.
We're going to use Hey Dude as our jumping off point,
but we are going to unpack and dive back
into the decade of the 90s.
We lived it, and now we're calling on all of our friends
to come back and relive it.
relive it. Listen to Hey, dude, the 90s called on the I heart
radio app Apple podcasts or wherever you get your podcasts.
Hey, I'm Lance Bass host of the new I heart podcast frosted
tips with Lance Bass. Do you ever think to yourself what advice
would Lance Bass and my favorite boy bands give me in this
situation? If you do, you've come to the right place because I'm
here to help and a different hot sexy teen crush boy band or each
week to guide you through life tell everybody everybody about my
new podcast and make sure to listen so we'll never ever have
to say bye bye bye. Listen to frosted tips with Lance Bass on
the I heart radio app Apple podcasts or wherever you listen
to podcasts.