Transcript for NASA Connect - Geometry and Algebra - Glow With the Flow

[Jennifer:] Hi, welcome
to NASA Connect.

The show that connects you to the
world of math, science, technology

and NASA, I am Jennifer Pulley
and this, he is Van Hughes.

[Van Hughes:] Jennifer,
what is that with blindfold?

[Jennifer:] One sec, we always
started NASA Connect episode

with a celebrity, who
introduces the show

and today I thought,
I surprise Van.

[Van Hughes:] Is it Norbert?

[Jennifer:] No Van, it's
definitely not Norbert.

However every time Norbert appears
with questions, have your Q cards

and the lesion guide ready to
answer the questions he gives you

and teachers every time Norbert
appears with remote, that's your Q

to pause the video tape and
discuss the Q part questions.

And teachers, don't forget, the
lesson guide could be downloaded

from our NASA Connect website.

[Van Hughes:] Okay,
now you have all that

[inaudible] information out of
the way, what about my surprise?

[Jennifer:] Okay, follow me.

[Van Hughes:] Jen, Jen.

[Van Hughes:] No way, Jackie
Chan you are celebrity.

I've seen all your movies,
I've seen Shanghai Noon,

Rush Hour, Rumble in the Bronx.

I can't leave you here at
NASA Langley Research Centre

and head for Virginia.

[Jennifer:] Van hang on;

[inaudible] don't really
like Jack introduce the show.

[Van Hughes:] Oh!

I am sorry.

[Jackie Chan:] Its
okay Van, you know,

during my visit here in NASA land.

I've learnt that this center is
one of the largest collection of

[inaudible] over the world.

In fact, I feel a movie in


Wow, how would I wonder?

On today's NASA Connect.

You learn how NASA engineers
and researchers use geometry

and algebra everyday in their work.

You will pass

[inaudible] just like
NASA researchers.

You get connected to a
really cool web activity

and take a sneak pip,
a new airplane.

Is it a bird or a plane?

So get ready, get set and go with
the flow, here on NASA Connect.

[Jennifer:] Okay, here is the deal.

Van and I are going to conduct a
little experiment about drag using


Van and I are riding
in the same kind of

[inaudible] with the
same amount of fuel.

These are concept; however, Van
is taller and heavier than I am.

These few variables height and
weight might affect the weight

and hopefully all parts of


I am the superior driver.

[Van Hughes:] I can't
change my weight,

but if I change the
variable of being taller and

[inaudible] and become more
streamline, I might have a chance.

[Jennifer:] No way,
how did you win?

[Van Hughes:] Let me explain
Jennifer, I've changed my shape,

which allow the air to flow
more smoothly around me.

Your shape interrupt the airflow
and cause drag; the slows you down

and allowed me to win.

[Jennifer:] So what is drag?

[Van Hughes:] Drag is the force
that oppose is resist motion.

The interruption or resistance
to air flow causes drag.

You probably experienced drag
when you ever stuck your hand

of the window of moving car.

When you extend your
like this with your


The force is drag pushes
your hand back, but when you

[inaudible] your hand like
this; they creates lift

and lifts your hand upward.

Lift and drag are few the
air dynamic forces that act

on airplane when it flies.

>> How the way are plane fly?

[Jennifer:] Well to
understand flight,

you must first understand air.

We are surrounded by air, all
the time but we can't feel it,

because the air pressure is
equal on all side to our body.

What if? We changed the air
pressure on one side of an outfit.

Check out this cool experiment.

Hey, why that the paper lift
up, when I blew across the top.

Well, when the paper is resting
against my chin like this.

The air pressure on top is equal
to the air pressure on the bottom,

but when I blow, I change
the air pressure on the top.

The shape of the paper in
its original position is kind

of like an air planes wing.

It is curved on the top, because
of this shape air molecules move

faster across the wings
tops and across its bottom.

Swiss mathematician
Daniel Bernoulli discovered

that faster moving fluids, such
is air, exert less pressure

than slower moving fluids.

Because of its shape the air over
the top of wings moves more quickly

and exerts less pressure.

When the pressure on top of the
wing is less than the pressure

under the wing lift is produced
and the air plain flies.

>> What does all this have to
do with algebra and geometry?

[Jennifer:] Everything, Geometry
is the study of shape and size.

Geometry was a currently
first develop

to help measure the
air and its objects.

Knowledge of geometry helps you
better understand things like

engineering and science.

[Van Hughes:] Algebra
is a mathematical

[inaudible] for solving problems.

Learning algebra is a bit like
learning to read and write.

Knowledge of Algebra can give
you more power to solve problems

and accomplish what
you want in life.

At NASA, engineers use algebra
and geometry, when they measure

and design models to be tested in


[Jennifer:] Like today's
NASA engineers,

(inaudible) use algebra
and geometry.

By blowing a certain amount
of air over models in a

[inaudible], the Wright
Brothers tested

and compared different wind shapes,

[inaudible] shapes and
(inaudible) shapes.

[Van Hughes:] Hey lets conducts
an experiment very similar

to the Wright Brothers and
test different shapes for drag.

[Jennifer:] Good idea Van, but
first teachers, make sure you check

up a NASA Connect website and down

with the lesson guide
for today's program.

In that you will find step-by-step
instructions and now this question

for today's classroom activity.


[Van Hughes:] In honor
of the Wright Brothers,

NASA Connect travels south to
Kill Devil Hills in North Carolina

to conduct today's
classroom activity.

>> Hi! Welcome to First
Flight Middle School,

Kill Devil Hills, North Carolina.

>> NASA Connect asked us
to share you, how do you

[inaudible] classroom activity.

It's called, what a Drag.

>> This activity has
three parts, in part one;

you learn how shape affects drag.

In part two, you learn how
surface area affect drag

and then part three, you apply
what's you learn from parts one

and two to determine the object
with a least amount of drag.

Make sure your teacher has a
lesson guide for this program.

All the steps and
materials are in it.

Before starting the experiment,
construct your drag apparatus,

then discuss these questions.

What is drag?

How would shape affect drag?

What is some direct and
indirect negative affects

of drag on a vehicle.

Now, let's test these
four shapes for drag.

First clarify, that each of
the shapes has the same amount

of frontal surface area.

And record your information
in the data sheet.

Next place two shapes on the
drag apparatus like this,

turn the pan on low, with
shape moves closer to the pan,

that's the one with the
least amount of drag.

Recorder observations
and repeat these steps,

is in different combinations
of the shape.

Look it together, which shape
has the least amount of drag,

the shape affect drag,
why or why not,

what other variables could
have affected the outcome

of the experiment?


[inaudible] nice job guys,

take five because will
be back a litter later

to continue this activity.

But first let's have
to NASA Langley to see,

how engineers there
are using algebra

to solve problems with drag.

Here is a wind tunnel to set
up a box stand to test model

with different shapes.

>> Well carry the point
in determine drag.

>> Why algebraic relationship
shows that a car has drag?

>> Explain the relationship
between pressure and glow?

>> This is one of NASA
Langley's many wind tunnels;

it's called the basic
aerodynamic research channel

[inaudible] sure.

Engineers like me use the

[inaudible] in a technique
called flow visualization,

to try to understand, how
the airflows run aircraft.

While looking at the
visualizing the air flow,

we can help aircraft
designer to create new shapes

at a more aerodynamic
and produced less drag.

Drag slows down the vehicle
or an object, as you observe

in the activity, just conduct.

Recently NASA Langley use
its experience in testing

and simulate aircraft to help

[inaudible] manufacture
visualizing describe the airflow

[inaudible], when we as
engineers with really like to see

as the air flowing continuously
from the front of the car

to the back of the car, like
the flow with a cylinder.

There is no interruption in the
airflow, when there is no drag.

Unfortunately, this is not
helping one can remind.

So we have to make air
planes and cars stream line.

This particular automobile stream
line, which mean, it was design

to offer minimum resistance to
airflow, because of it shape,

this car has lower drag.

>> You know that simply
call activity, the

[inaudible] have the lowest
drag, because of its shape.

>> That's right, the
shape of aeroplanes

and cars is mainly determine
by aerodynamics and safety,

however a car has additional
factors and they affected shape.

The vehicle must look
good for people to buy,

the passenger must be comfortable,
and a vehicle must be able

to transport people, cargo or both.

With this in mind automotive
engineers use geometry

to design cars with one of three
shapes, a hatch back, a square back

or notch back, which
of the three shapes,

do you think with
have a highest drag?

>> Looks like the notch
back has the most drag.

>> You're right, after
deciding on the shape to test,

we created a scale model for
the typical passive vehicle

with notch back design to
visualize and measure the airflow

around this model, we use the

[inaudible] and materials like
kerosene and titanium dioxide,

a white color substance
used in paint.

Visualizing the airflow
provides a picture

of how the air moves
around the vehicle.

>> Okay so how do you
visualize airflow?

We can't really see air, can you?

>> No, you can't and
that's a good question.

We have special material to
really can see air flowing,

so we mix titanium dioxide and
kerosene together and applied it

to the surface of the model.

We turn on the wind tunnel and
as air flowed over the model;

the kerosene evaporated
or turn into a gas.

The titanium dioxide
left in the surface,

shows us an airflow pattern.

This pattern tells us, how the air
is moving close to the surface.

The measurement reflects to allow
us to describe the air's properties

in motion with numbers.

>> Do they allow, what's
really cool you know

but what does this pattern
say about the shape of the car

and the drag it produces?

>> Well this pattern tells us
that the air is actually traveling

in the same directions a car

or in other words
towards the back window.

This is called reserve flow,
reverse flow creates low pressure

on the back of the vehicle,
which increases drag.

Remember this drawing, see
how the air flows smoothly

over the cylinder and comes
together again in the back,

although this isn't helping what
in a real world, the air pressure

in the front PF is
the same or equal

to the pressure in the back PB.

When the pressure in the
front is equal to the pressure

in the back there is no drag.

However look it our
notch back model,

see how the airflow separates
at the back of the vehicle

and the air actually begins to
flow in the reverse direction.

This is reverse flow and
the pressure in the front

of the model is greater than
the pressure in the back.

When the pressure in the front
is greater than the pressure

in the back you have drag.

>> Through our visualization helps
us understand how the air flows

over the model, when the
work to measure the pressures

on the surface we had to
use additional techniques.

The most exiting pressures
sensitive thing.

In addition to NASA Langley NASA
Glenn Research Center in Ohio

and NASA Ames Research Center

in California use
pressure sensitive paint

in wind tunnel test.

Pressure sensitive paint or PSP
is a special paint that glows

when exposed to blue light.

The glow is really due to
special molecules embedded

in the paint called luminophores.

>> Luminophores something word
that comes from illuminate.

>> That's right; these
luminophores are exited

or giving excess energy
by the blue light.

The luminophores don't like to
have excess energy, so they get rid

of it by either glowing,
or by bumping

into near by oxygen molecules.

The behavior of the luminophores
allows us to see a relationship

between the brightness
so there glow

and the pressure on the surface.

>> A relationship
sounds like algebra.

>> That's right, I use algebra in
my work everyday, let me show you,

remember when I said that the
behavior of luminophores allow us

to relate the brightness
of the glow to the pressure

on the surface, this is done
using a graph like this.

The current chronograph
shows an inverse relationship

between pressure and glow.

When glow increases, we know
the pressure is decrease

or when glow decreases we know
the pressure has increase,

this inverse relationship
can be represented

with the following
algebraic equation,

pressure equals quality
glow minus one divided

by the slope of the curve.

Using the graph in this algebraic
equation we solve for pressure.

The pressures we calculate can be
displayed using different colors

like this; the red region show
where the pressures are high

and the blue region show
where the pressures are low.

As you can see, the
pressures in the front

of the car are higher then
the pressures in the back.

As we calculated earlier this
difference determines the

vehicle stray.

This information is used by car
designers to decide if the shape

or geometry of the car
needs to be change.

>> If I were a car designer,

I change the notch
back shape of the car.

Clinch too much drag.

>> Oh then, the research
conducted here

at the NASA Langley
Research Center,

will be used by automotive
engineers and designers

to create new designs and
shape which reduced drag

and better fuel efficiency.

This allows drivers like us to save
money and protect the environment.

>> Okay, we've seen how
different shapes affect drag.

Now let's head back, to
first like middle school

and see what would happen

if we change the frontal
surface area of an object.

Are you ready guys?

>> Ready Jennifer and let's find
out how surface area affects drag.

>> Your teacher will give each
group a copy of the disk patterns

from the lesson guide.

Select and construct five discs.

Look at one of the disc what
do you think the area is,

make a prediction
and write it down,

now calculate the actual
area what is the difference

between your prediction and
the actual area, are you close,

repeat these steps for each disc.

Before beginning the experiment,
construct the test track,

choose any disc and
place it on the front

of the test vehicle like this.

Place the vehicles
on the start line;

make sure the string
is nice and tight.

Predicted distance that the
test vehicle would travel

when the fan is turned
on and write it down.

>> I predict they'll travel
long, forty two centimeters.

>> I predict they will
travel fifty centimeters.

>> Turn the fan on high for
approximately 10 seconds,

this is only a suggested time.

Your time will depend on the
fan speed and test vehicles.

Now, measure the distance that
the test vehicle moves backward

and record it on the data sheet.

Calculate the difference
between the predicted distance

and the actual distance
and record your answer.

How did you do?

Now test the other disc.

>> Now that we've gathered
our data, let's create a graph

that shows the relationship

between funnel surface
area and distance.

Could I have one member
of each group to come

up and graph their data?

>> Great job guys,
let's look at the graph

and answer some questions.

What kind of graph is it?

Do you see a correlation
if so, what kind is it.

Which surface area produce
the least amount of drag?

Now let's put it all
together, look at the data

from the first experiment you did.

Which shape had the
least amount of drag?

>> The shape, now look at your data

from the second experiment
we did on surface area.

What did you find out about
the surface area and drag?

Based on your results, which of
these four tetra hydrants should

have the least amount of drag?

How can we test your predictions?

>> Put the shapes on the drag
stand and see what happens.

>>: Great, let's do it.

>> We would like to thank
the AIAA student mentors

from North Carolina
State University.

>> Good job guys, thus far
you have seen this tool -

some of the tools for research.

That being designed,
construction, testing and analysis

of an experiment, but you know
what NASA uses some other tools

for research.

Computer simulations and what
will it help _____ Norbert here;

we are going to transport you

to Fernbank Science
Center Atlanta Georgia.

>> Fernbank Science Center
is a science resource centre

for _____ county school system.

This had a relationship with NASA
since the earlier polymission

and recently installed the NASA
Aeronautics Education Laboratory

to use in its education programs.

Where do you think you are
at Fernbank are students

from the near Middle School, who
in addition to the problem featured

to web simulation at Max or
Mars Airborne Explorer create a

specially for NASA
Connect by

>> A Norbert's lab pick
the activity bundle.

>> You will get to create a Mars
Exploration Aircraft employed

of a simulated mercantile.

You will be able to
see the relationships

between the thrust, drag, _____.

Your mission is to polythemers
aircraft and release a number

of probes that must land
on designated targets.

The right combination in balance
will lead to a successful flight.

>> In past classroom
exchange brings

to teach assistance the
opportunity to collaborate

with peers, expert and
others using e-pass free

telecommunications and
collaborate tools and teachers.

Be sure to visit Norbert's lab and
browse a section called manger.

A special section to help guide
teachers and use in activities

that have educational
technology interwoven.

A special thanks to another NASA
Connect online partner,

divided to space news if
offers special quarrels to kids

and teachers that and

And the final things to
our AIAA _____ Georgiatech.

>> Well I thing that's a rap
from my end bringing with a power

of digital learning, I'm sure we
came right for NASA Connect online.

>> Okay, let's review so far we've
learned how NASA engineers use

geometry and algebra.

Flow visualization
and glowing paints

to help them create more
Aerodynamic vehicles and how shape

and service area affect drag.

>> We have also learnt how computer
technology cannot use our problems

that out of this world.

Now, let's learn how NASA
engineers are using geometry

to create a concept airplane that
looks a lot like a flying wing.

>> Describe the differences
between the blended wing body

and today's commercial aeroplane.

>>: How do NASA engineers
use geometry

to estimate control surface area?

>>: What is

[inaudible] features will increase
to drag on a low speed vehicle?

How could engineers
compensate with that drag?

>>: The blended wing body
will be BWB we call it

for short is an advanced
concept passenger aeroplane.

That means that we are still
on a process of deciding

and testing what would
be the best design.

So far early study's estimate
the blended wing body will hold

up the five hundred
passengers, have a wing span

of two hundred forty seven feet, a
length of a hundred and sixty feet

and be more than forty
feet or a four storey high.

It kind of resembles
of flying wing.

Engineers believe the BWB has
potential to perform better

than traditional tube with wings
aeroplane like the Boeing-747.

Some estimates predict that this
new aeroplane will reduce operating

cost and

[inaudible] the aeroplane uses.

This means your airline
ticket may cost less.

>> So, Windy what makes the
blended wing body so special?

>> It's shape.

Since we've been discussing shape
and geometry in today's program,

let me show you what
makes the BWB different

from another air planes today.

>> If you look down on the top of
the plane, you can see that is

[inaudible] that's the
part of people ride in

and the wing a blender together.

That's how it got its name
The Blended Wing body.

Now from the front of the
BWB or the frontal view,

we can see that there is a
smooth transition from the

[inaudible] to large to the wings.

This shape allows
more people to sit in

[inaudible] and even
out into the wings.

Remember the picture
of the stream line car

[inaudible] showed
you, just like a car

when an airplane has a smooth
shape, it can help reduce drag.

Do you see anything else
that makes the BWB different

from another airplane.

>>: You know it doesn't have
a tail like other airplanes.

>>: Right.

>>: Just like running the wing and

[inaudible] lot's together helps

to reduce drag taking
off those the horizontal

and vertical tails
also helps reduce drag.

Drag which you've learned
about earlier losses thrust,

thrust before that propels the
airplane is usually provided

by Jet engines.

But if the airplane has too much
drag, it will need more thrust

for engine power however
when airplane is designed

for less drag like the
BWB less thrust is needed.

So what is this all mean?

Less thrust means
less fuel is needed.

>>: And less fuel means
less money to buy a ticket.

>> You got it.

Now, Windy you know
you said earlier

that BWB is just a concept airplane

so I guess that means it hasn't

[inaudible] yet.

>> Right, it would be too expensive
to build the full size BWB.

NASA going engineers come together
and design some scale models,

that way they can test it
before they build the full size

blended wind body.

>> Now you said some scale models,
is that mean that there is going

to be more than one
model of the BWB?

>>: Absolutely, if we only got one
model we couldn't collect enough

information so we build the
model that's approximately 1%

of the size of the BWB.

>> Hey let's do the math.

>> What would the 1% model
of the BWB look like?

Would it fit in your
classroom or in a shoe box?

>>: I know let's figure it out.

When you told this earlier that the
BWB will be two hundred forty seven

feet large, one hundred sixty feet
long and forty feet tall using

that a map let's take one percent
of each of those measurements.

>>: Okay, 1% of two forty
seven is two point four seven

or about two and half feet wide.

1% of one sixty is one point six
or about one and half feet long.

1% of forty is point four
or about half a top so ya,

1% model of the BWB should
definitely fit your class room,

right Wendy!

[Wendy:] That's right
and here it is.

As I said earlier building just one
scale model like this can give us

all the information we needed.

So we got a two percent, three
percent and a four percent model.

They all be tested here at NASA

[inaudible] and the Wind tunnels

to determine performance
and stability.

While Wind tunnel test can help us
predict how the BWB we will perform

it can't tell us how a
real pilot will be able

to petrol it in the air.


[inaudible] is building another the
subs scaled model called the 'Low

Speed Vehicle' or LSV
and it will actually fly.

We will take our LSV
Wind tunnel predictions

and compare them to actual

[inaudible] data.

The flight test will take place

at NASA driving flight
research centre in California.

Engineers want to
learn how to control

and stabilize this new concept
airplane, so we fly safely.

In the Wind tunnel you
just can't simulate that.

LSV is about fourteen percent
the size of a full sized BWB.

Fourteen percent model of the BWB
is about thirty-five feet wide,

twenty-two feet long
and sixty high.

Remember in classroom
activity when you determine

that a grater prevalence surface
area produced greater drag,

let's look at the frontal view of
the fourteen percent BWB model.

To estimate the frontal surface
area all we need is the width,

the height and a little geometry.

First, we take the
frontal view and divide it

into parts chosen
geometric shapes like this.

Then we estimate the area
which geometric shape

and add them together to get
the total frontal surface area.

Next we combine the total
frontal surface area

with all the flight test
data with collective

and calculate the drag force
for this particular model.

>> We knew that the fly we
need a certain amount of

[inaudible] to become drag force.

>> Okay so figuring me out
the frontal surface area

of the fourteen percent
model of calculate drag

which then determines so
much thrust is needed.

>>: Right.

>>: Right, this is just
a concept airplane right,

I mean what if you want to
add something, may be you like

in observation that can talk.

>>: An observation

[inaudible] would definitely
increase the frontal surface area

[inaudible] which
would then increase

[inaudible], air become bad amount
of drag need to increase thrust

by adding more powerful engines.

>> No one that applies the go cart


>> My final surface area was a
greater than his because I didn't

[inaudible] down into
aero-dynamic shape.

This greater frontal surface area
created more drag and I lost.

However, if I had more than less I
could have easily overcome the drag

and left

[inaudible] in the dust.

>> Now you know what,

[inaudible] come to that.

>> yeah.

>> You know we all
people made the connection

which mean aeronautical research
conducted your NASA and the math,

science and technology that you
do in your classes everyday.

>> Jennifer and I would love to
hear from you, your questions,

comments or suggestions.

So write us at NASA Connect, NASA

[inaudible] research center
mail stop four hundred.

[inaudible] Virginia two three six
eight one or send us an e-mail


>> Hey teacher if you would like
a video tape of this program

and we are accompanying

[inaudible] check out
the NASA connect website,

from our side if you link to

[inaudible] the NASA central
operation of resources

for educators or linked

to the NASA educator
resource centre network.

We would like to think everyone
who have make this episode

of NASA Connect possible,
especially Jackie Chan.

>> No, I'm thanking you
and thank you Bryan,

thank you NASA for inviting me.

I learned a lot of things because
when I was young I just only thing

I know was Martial Arts.

>> Taking

[inaudible] all kinds of things and
never know educating importantance.

Whenever I go, I will
support the children

because education is
very important, remember.

>> You heard it right from Jackie
Chan I will see you next time.

>> Yeah.

>> Well to understand flight
you must first under--

>> That's right, the

[inaudible] of--

>> Now, let's learn
how NASA researchers

or NASA engineers are
using geometry as they--

>> remember the


>> I would to thank

[ Laughter ]

>> So get ready, get set
and flow and go flow--

>> [inaudible].


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