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Transcript for NASA Connect - Geometry and Algebra - Glow With the Flow
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[Jennifer:] Hi, welcome
to NASA Connect.
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The show that connects you to the
world of math, science, technology
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and NASA, I am Jennifer Pulley
and this, he is Van Hughes.
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[Van Hughes:] Jennifer,
what is that with blindfold?
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[Jennifer:] One sec, we always
started NASA Connect episode
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with a celebrity, who
introduces the show
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and today I thought,
I surprise Van.
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[Van Hughes:] Is it Norbert?
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[Jennifer:] No Van, it's
definitely not Norbert.
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However every time Norbert appears
with questions, have your Q cards
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and the lesion guide ready to
answer the questions he gives you
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and teachers every time Norbert
appears with remote, that's your Q
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to pause the video tape and
discuss the Q part questions.
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And teachers, don't forget, the
lesson guide could be downloaded
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from our NASA Connect website.
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[Van Hughes:] Okay,
now you have all that
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[inaudible] information out of
the way, what about my surprise?
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[Jennifer:] Okay, follow me.
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[Van Hughes:] Jen, Jen.
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[Van Hughes:] No way, Jackie
Chan you are celebrity.
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I've seen all your movies,
I've seen Shanghai Noon,
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Rush Hour, Rumble in the Bronx.
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I can't leave you here at
NASA Langley Research Centre
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and head for Virginia.
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[Jennifer:] Van hang on;
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[inaudible] don't really
like Jack introduce the show.
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[Van Hughes:] Oh!
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I am sorry.
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[Jackie Chan:] Its
okay Van, you know,
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during my visit here in NASA land.
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I've learnt that this center is
one of the largest collection of
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[inaudible] over the world.
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In fact, I feel a movie in
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[inaudible].
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Wow, how would I wonder?
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On today's NASA Connect.
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You learn how NASA engineers
and researchers use geometry
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and algebra everyday in their work.
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You will pass
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[inaudible] just like
NASA researchers.
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You get connected to a
really cool web activity
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and take a sneak pip,
a new airplane.
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Is it a bird or a plane?
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So get ready, get set and go with
the flow, here on NASA Connect.
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[Jennifer:] Okay, here is the deal.
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Van and I are going to conduct a
little experiment about drag using
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[inaudible].
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Van and I are riding
in the same kind of
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[inaudible] with the
same amount of fuel.
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These are concept; however, Van
is taller and heavier than I am.
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These few variables height and
weight might affect the weight
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and hopefully all parts of
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[inaudible].
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I am the superior driver.
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[Van Hughes:] I can't
change my weight,
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but if I change the
variable of being taller and
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[inaudible] and become more
streamline, I might have a chance.
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[Jennifer:] No way,
how did you win?
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[Van Hughes:] Let me explain
Jennifer, I've changed my shape,
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which allow the air to flow
more smoothly around me.
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Your shape interrupt the airflow
and cause drag; the slows you down
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and allowed me to win.
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[Jennifer:] So what is drag?
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[Van Hughes:] Drag is the force
that oppose is resist motion.
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The interruption or resistance
to air flow causes drag.
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You probably experienced drag
when you ever stuck your hand
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of the window of moving car.
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When you extend your
like this with your
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[inaudible].
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The force is drag pushes
your hand back, but when you
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[inaudible] your hand like
this; they creates lift
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and lifts your hand upward.
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Lift and drag are few the
air dynamic forces that act
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on airplane when it flies.
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>> How the way are plane fly?
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[Jennifer:] Well to
understand flight,
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you must first understand air.
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We are surrounded by air, all
the time but we can't feel it,
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because the air pressure is
equal on all side to our body.
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What if? We changed the air
pressure on one side of an outfit.
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Check out this cool experiment.
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Hey, why that the paper lift
up, when I blew across the top.
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Well, when the paper is resting
against my chin like this.
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The air pressure on top is equal
to the air pressure on the bottom,
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but when I blow, I change
the air pressure on the top.
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The shape of the paper in
its original position is kind
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of like an air planes wing.
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It is curved on the top, because
of this shape air molecules move
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faster across the wings
tops and across its bottom.
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Swiss mathematician
Daniel Bernoulli discovered
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that faster moving fluids, such
is air, exert less pressure
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than slower moving fluids.
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Because of its shape the air over
the top of wings moves more quickly
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and exerts less pressure.
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When the pressure on top of the
wing is less than the pressure
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under the wing lift is produced
and the air plain flies.
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>> What does all this have to
do with algebra and geometry?
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[Jennifer:] Everything, Geometry
is the study of shape and size.
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Geometry was a currently
first develop
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to help measure the
air and its objects.
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Knowledge of geometry helps you
better understand things like
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engineering and science.
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[Van Hughes:] Algebra
is a mathematical
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[inaudible] for solving problems.
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Learning algebra is a bit like
learning to read and write.
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Knowledge of Algebra can give
you more power to solve problems
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and accomplish what
you want in life.
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At NASA, engineers use algebra
and geometry, when they measure
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and design models to be tested in
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[inaudible].
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[Jennifer:] Like today's
NASA engineers,
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(inaudible) use algebra
and geometry.
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By blowing a certain amount
of air over models in a
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[inaudible], the Wright
Brothers tested
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and compared different wind shapes,
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[inaudible] shapes and
(inaudible) shapes.
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[Van Hughes:] Hey lets conducts
an experiment very similar
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to the Wright Brothers and
test different shapes for drag.
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[Jennifer:] Good idea Van, but
first teachers, make sure you check
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up a NASA Connect website and down
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with the lesson guide
for today's program.
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In that you will find step-by-step
instructions and now this question
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for today's classroom activity.
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Van.
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[Van Hughes:] In honor
of the Wright Brothers,
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NASA Connect travels south to
Kill Devil Hills in North Carolina
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to conduct today's
classroom activity.
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>> Hi! Welcome to First
Flight Middle School,
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Kill Devil Hills, North Carolina.
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>> NASA Connect asked us
to share you, how do you
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[inaudible] classroom activity.
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It's called, what a Drag.
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>> This activity has
three parts, in part one;
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you learn how shape affects drag.
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In part two, you learn how
surface area affect drag
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and then part three, you apply
what's you learn from parts one
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and two to determine the object
with a least amount of drag.
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Make sure your teacher has a
lesson guide for this program.
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All the steps and
materials are in it.
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Before starting the experiment,
construct your drag apparatus,
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then discuss these questions.
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What is drag?
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How would shape affect drag?
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What is some direct and
indirect negative affects
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of drag on a vehicle.
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Now, let's test these
four shapes for drag.
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First clarify, that each of
the shapes has the same amount
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of frontal surface area.
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And record your information
in the data sheet.
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Next place two shapes on the
drag apparatus like this,
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turn the pan on low, with
shape moves closer to the pan,
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that's the one with the
least amount of drag.
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Recorder observations
and repeat these steps,
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is in different combinations
of the shape.
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Look it together, which shape
has the least amount of drag,
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the shape affect drag,
why or why not,
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what other variables could
have affected the outcome
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of the experiment?
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Thanks
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[inaudible] nice job guys,
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take five because will
be back a litter later
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to continue this activity.
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But first let's have
to NASA Langley to see,
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how engineers there
are using algebra
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to solve problems with drag.
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Here is a wind tunnel to set
up a box stand to test model
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with different shapes.
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>> Well carry the point
in determine drag.
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>> Why algebraic relationship
shows that a car has drag?
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>> Explain the relationship
between pressure and glow?
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>> This is one of NASA
Langley's many wind tunnels;
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it's called the basic
aerodynamic research channel
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[inaudible] sure.
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Engineers like me use the
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[inaudible] in a technique
called flow visualization,
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to try to understand, how
the airflows run aircraft.
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While looking at the
visualizing the air flow,
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we can help aircraft
designer to create new shapes
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at a more aerodynamic
and produced less drag.
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Drag slows down the vehicle
or an object, as you observe
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in the activity, just conduct.
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Recently NASA Langley use
its experience in testing
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and simulate aircraft to help
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[inaudible] manufacture
visualizing describe the airflow
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[inaudible], when we as
engineers with really like to see
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as the air flowing continuously
from the front of the car
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to the back of the car, like
the flow with a cylinder.
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There is no interruption in the
airflow, when there is no drag.
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Unfortunately, this is not
helping one can remind.
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So we have to make air
planes and cars stream line.
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This particular automobile stream
line, which mean, it was design
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to offer minimum resistance to
airflow, because of it shape,
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this car has lower drag.
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>> You know that simply
call activity, the
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[inaudible] have the lowest
drag, because of its shape.
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>> That's right, the
shape of aeroplanes
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and cars is mainly determine
by aerodynamics and safety,
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however a car has additional
factors and they affected shape.
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The vehicle must look
good for people to buy,
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the passenger must be comfortable,
and a vehicle must be able
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to transport people, cargo or both.
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With this in mind automotive
engineers use geometry
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to design cars with one of three
shapes, a hatch back, a square back
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or notch back, which
of the three shapes,
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do you think with
have a highest drag?
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>> Looks like the notch
back has the most drag.
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>> You're right, after
deciding on the shape to test,
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we created a scale model for
the typical passive vehicle
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with notch back design to
visualize and measure the airflow
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around this model, we use the
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[inaudible] and materials like
kerosene and titanium dioxide,
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a white color substance
used in paint.
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Visualizing the airflow
provides a picture
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of how the air moves
around the vehicle.
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>> Okay so how do you
visualize airflow?
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We can't really see air, can you?
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>> No, you can't and
that's a good question.
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We have special material to
really can see air flowing,
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so we mix titanium dioxide and
kerosene together and applied it
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to the surface of the model.
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We turn on the wind tunnel and
as air flowed over the model;
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the kerosene evaporated
or turn into a gas.
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The titanium dioxide
left in the surface,
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shows us an airflow pattern.
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This pattern tells us, how the air
is moving close to the surface.
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The measurement reflects to allow
us to describe the air's properties
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in motion with numbers.
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>> Do they allow, what's
really cool you know
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but what does this pattern
say about the shape of the car
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and the drag it produces?
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>> Well this pattern tells us
that the air is actually traveling
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in the same directions a car
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or in other words
towards the back window.
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This is called reserve flow,
reverse flow creates low pressure
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on the back of the vehicle,
which increases drag.
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Remember this drawing, see
how the air flows smoothly
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over the cylinder and comes
together again in the back,
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although this isn't helping what
in a real world, the air pressure
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in the front PF is
the same or equal
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to the pressure in the back PB.
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When the pressure in the
front is equal to the pressure
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in the back there is no drag.
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However look it our
notch back model,
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see how the airflow separates
at the back of the vehicle
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and the air actually begins to
flow in the reverse direction.
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This is reverse flow and
the pressure in the front
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of the model is greater than
the pressure in the back.
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When the pressure in the front
is greater than the pressure
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in the back you have drag.
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>> Through our visualization helps
us understand how the air flows
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over the model, when the
work to measure the pressures
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on the surface we had to
use additional techniques.
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The most exiting pressures
sensitive thing.
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In addition to NASA Langley NASA
Glenn Research Center in Ohio
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and NASA Ames Research Center
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in California use
pressure sensitive paint
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in wind tunnel test.
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Pressure sensitive paint or PSP
is a special paint that glows
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when exposed to blue light.
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The glow is really due to
special molecules embedded
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in the paint called luminophores.
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>> Luminophores something word
that comes from illuminate.
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>> That's right; these
luminophores are exited
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or giving excess energy
by the blue light.
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The luminophores don't like to
have excess energy, so they get rid
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of it by either glowing,
or by bumping
[00:13:16.509]
into near by oxygen molecules.
[00:13:18.699]
The behavior of the luminophores
allows us to see a relationship
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between the brightness
so there glow
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and the pressure on the surface.
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>> A relationship
sounds like algebra.
[00:13:28.869]
>> That's right, I use algebra in
my work everyday, let me show you,
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remember when I said that the
behavior of luminophores allow us
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to relate the brightness
of the glow to the pressure
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on the surface, this is done
using a graph like this.
[00:13:40.859]
The current chronograph
shows an inverse relationship
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between pressure and glow.
[00:13:45.189]
When glow increases, we know
the pressure is decrease
[00:13:47.559]
or when glow decreases we know
the pressure has increase,
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this inverse relationship
can be represented
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with the following
algebraic equation,
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pressure equals quality
glow minus one divided
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by the slope of the curve.
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Using the graph in this algebraic
equation we solve for pressure.
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The pressures we calculate can be
displayed using different colors
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like this; the red region show
where the pressures are high
[00:14:11.269]
and the blue region show
where the pressures are low.
[00:14:14.119]
As you can see, the
pressures in the front
[00:14:16.159]
of the car are higher then
the pressures in the back.
[00:14:18.919]
As we calculated earlier this
difference determines the
[00:14:21.719]
vehicle stray.
[00:14:23.149]
This information is used by car
designers to decide if the shape
[00:14:26.029]
or geometry of the car
needs to be change.
[00:14:27.759]
>> If I were a car designer,
[00:14:30.259]
I change the notch
back shape of the car.
[00:14:32.229]
Clinch too much drag.
[00:14:33.769]
>> Oh then, the research
conducted here
[00:14:35.649]
at the NASA Langley
Research Center,
[00:14:37.129]
will be used by automotive
engineers and designers
[00:14:39.719]
to create new designs and
shape which reduced drag
[00:14:42.229]
and better fuel efficiency.
[00:14:43.829]
This allows drivers like us to save
money and protect the environment.
[00:14:48.629]
>> Okay, we've seen how
different shapes affect drag.
[00:14:52.289]
Now let's head back, to
first like middle school
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and see what would happen
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if we change the frontal
surface area of an object.
[00:15:00.419]
Are you ready guys?
[00:15:01.859]
>> Ready Jennifer and let's find
out how surface area affects drag.
[00:15:05.949]
>> Your teacher will give each
group a copy of the disk patterns
[00:15:09.309]
from the lesson guide.
[00:15:10.589]
Select and construct five discs.
[00:15:13.289]
Look at one of the disc what
do you think the area is,
[00:15:16.869]
make a prediction
and write it down,
[00:15:19.019]
now calculate the actual
area what is the difference
[00:15:22.549]
between your prediction and
the actual area, are you close,
[00:15:27.689]
repeat these steps for each disc.
[00:15:30.869]
Before beginning the experiment,
construct the test track,
[00:15:34.409]
choose any disc and
place it on the front
[00:15:36.499]
of the test vehicle like this.
[00:15:38.849]
Place the vehicles
on the start line;
[00:15:41.179]
make sure the string
is nice and tight.
[00:15:44.239]
Predicted distance that the
test vehicle would travel
[00:15:46.959]
when the fan is turned
on and write it down.
[00:15:49.879]
>> I predict they'll travel
long, forty two centimeters.
[00:15:53.489]
>> I predict they will
travel fifty centimeters.
[00:15:56.389]
>> Turn the fan on high for
approximately 10 seconds,
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this is only a suggested time.
[00:16:02.359]
Your time will depend on the
fan speed and test vehicles.
[00:16:06.249]
Now, measure the distance that
the test vehicle moves backward
[00:16:10.249]
and record it on the data sheet.
[00:16:12.389]
Calculate the difference
between the predicted distance
[00:16:15.059]
and the actual distance
and record your answer.
[00:16:18.369]
How did you do?
[00:16:20.519]
Now test the other disc.
[00:16:25.499]
>> Now that we've gathered
our data, let's create a graph
[00:16:28.259]
that shows the relationship
[00:16:29.639]
between funnel surface
area and distance.
[00:16:31.829]
Could I have one member
of each group to come
[00:16:34.949]
up and graph their data?
[00:16:40.359]
[00:16:41.689]
>> Great job guys,
let's look at the graph
[00:16:43.759]
and answer some questions.
[00:16:45.839]
What kind of graph is it?
[00:16:48.369]
Do you see a correlation
if so, what kind is it.
[00:16:53.889]
[00:16:55.259]
Which surface area produce
the least amount of drag?
[00:16:59.049]
Now let's put it all
together, look at the data
[00:17:01.399]
from the first experiment you did.
[00:17:03.519]
Which shape had the
least amount of drag?
[00:17:06.949]
>> The shape, now look at your data
[00:17:11.269]
from the second experiment
we did on surface area.
[00:17:14.119]
What did you find out about
the surface area and drag?
[00:17:18.639]
Based on your results, which of
these four tetra hydrants should
[00:17:22.359]
have the least amount of drag?
[00:17:24.599]
How can we test your predictions?
[00:17:26.879]
>> Put the shapes on the drag
stand and see what happens.
[00:17:30.679]
>>: Great, let's do it.
[00:17:31.409]
>> We would like to thank
the AIAA student mentors
[00:17:34.999]
from North Carolina
State University.
[00:17:37.299]
>> Good job guys, thus far
you have seen this tool -
[00:17:41.359]
some of the tools for research.
[00:17:42.969]
That being designed,
construction, testing and analysis
[00:17:46.639]
of an experiment, but you know
what NASA uses some other tools
[00:17:50.169]
for research.
[00:17:51.239]
Computer simulations and what
will it help _____ Norbert here;
[00:17:54.839]
we are going to transport you
[00:17:56.349]
to Fernbank Science
Center Atlanta Georgia.
[00:17:59.359]
>> Fernbank Science Center
is a science resource centre
[00:18:01.829]
for _____ county school system.
[00:18:03.829]
This had a relationship with NASA
since the earlier polymission
[00:18:06.949]
and recently installed the NASA
Aeronautics Education Laboratory
[00:18:10.099]
to use in its education programs.
[00:18:12.679]
Where do you think you are
at Fernbank are students
[00:18:14.509]
from the near Middle School, who
in addition to the problem featured
[00:18:17.439]
to web simulation at Max or
Mars Airborne Explorer create a
[00:18:21.879]
specially for NASA
Connect by space.com.
[00:18:24.819]
>> A Norbert's lab pick
the activity bundle.
[00:18:27.609]
>> You will get to create a Mars
Exploration Aircraft employed
[00:18:31.619]
of a simulated mercantile.
[00:18:33.349]
You will be able to
see the relationships
[00:18:36.739]
between the thrust, drag, _____.
[00:18:39.689]
Your mission is to polythemers
aircraft and release a number
[00:18:43.109]
of probes that must land
on designated targets.
[00:18:46.149]
The right combination in balance
will lead to a successful flight.
[00:18:50.039]
>> In past classroom
exchange brings
[00:18:52.299]
to teach assistance the
opportunity to collaborate
[00:18:54.829]
with peers, expert and
others using e-pass free
[00:18:58.189]
telecommunications and
collaborate tools and teachers.
[00:19:01.759]
Be sure to visit Norbert's lab and
browse a section called manger.
[00:19:05.509]
A special section to help guide
teachers and use in activities
[00:19:08.529]
that have educational
technology interwoven.
[00:19:11.829]
A special thanks to another NASA
Connect online partner space.com,
[00:19:16.389]
divided to space news if
offers special quarrels to kids
[00:19:19.919]
and teachers that
spacekids.com and teachspace.com.
[00:19:24.019]
And the final things to
our AIAA _____ Georgiatech.
[00:19:26.919]
>> Well I thing that's a rap
from my end bringing with a power
[00:19:31.009]
of digital learning, I'm sure we
came right for NASA Connect online.
[00:19:34.229]
>> Okay, let's review so far we've
learned how NASA engineers use
[00:19:39.219]
geometry and algebra.
[00:19:41.409]
Flow visualization
and glowing paints
[00:19:43.589]
to help them create more
Aerodynamic vehicles and how shape
[00:19:47.099]
and service area affect drag.
[00:19:49.129]
>> We have also learnt how computer
technology cannot use our problems
[00:19:52.599]
that out of this world.
[00:19:53.719]
Now, let's learn how NASA
engineers are using geometry
[00:19:57.679]
to create a concept airplane that
looks a lot like a flying wing.
[00:20:05.499]
>> Describe the differences
between the blended wing body
[00:20:08.579]
and today's commercial aeroplane.
[00:20:10.499]
>>: How do NASA engineers
use geometry
[00:20:13.079]
to estimate control surface area?
[00:20:15.339]
>>: What is
[00:20:15.989]
[inaudible] features will increase
to drag on a low speed vehicle?
[00:20:19.219]
How could engineers
compensate with that drag?
[00:20:22.119]
>>: The blended wing body
will be BWB we call it
[00:20:25.709]
for short is an advanced
concept passenger aeroplane.
[00:20:29.719]
That means that we are still
on a process of deciding
[00:20:32.319]
and testing what would
be the best design.
[00:20:34.839]
So far early study's estimate
the blended wing body will hold
[00:20:38.099]
up the five hundred
passengers, have a wing span
[00:20:40.779]
of two hundred forty seven feet, a
length of a hundred and sixty feet
[00:20:44.619]
and be more than forty
feet or a four storey high.
[00:20:47.769]
It kind of resembles
of flying wing.
[00:20:50.489]
Engineers believe the BWB has
potential to perform better
[00:20:53.879]
than traditional tube with wings
aeroplane like the Boeing-747.
[00:20:58.389]
Some estimates predict that this
new aeroplane will reduce operating
[00:21:01.909]
cost and
[00:21:03.019]
[inaudible] the aeroplane uses.
[00:21:04.549]
This means your airline
ticket may cost less.
[00:21:08.669]
>> So, Windy what makes the
blended wing body so special?
[00:21:12.519]
>> It's shape.
[00:21:13.959]
Since we've been discussing shape
and geometry in today's program,
[00:21:17.469]
let me show you what
makes the BWB different
[00:21:19.449]
from another air planes today.
[00:21:22.139]
>> If you look down on the top of
the plane, you can see that is
[00:21:24.779]
[inaudible] that's the
part of people ride in
[00:21:26.909]
and the wing a blender together.
[00:21:29.539]
That's how it got its name
The Blended Wing body.
[00:21:32.769]
Now from the front of the
BWB or the frontal view,
[00:21:36.399]
we can see that there is a
smooth transition from the
[00:21:39.369]
[inaudible] to large to the wings.
[00:21:40.879]
This shape allows
more people to sit in
[00:21:42.789]
[inaudible] and even
out into the wings.
[00:21:46.159]
Remember the picture
of the stream line car
[00:21:48.499]
[inaudible] showed
you, just like a car
[00:21:50.679]
when an airplane has a smooth
shape, it can help reduce drag.
[00:21:55.099]
Do you see anything else
that makes the BWB different
[00:21:58.079]
from another airplane.
[00:21:59.909]
>>: You know it doesn't have
a tail like other airplanes.
[00:22:04.209]
>>: Right.
[00:22:05.159]
>>: Just like running the wing and
[00:22:06.669]
[inaudible] lot's together helps
[00:22:07.929]
to reduce drag taking
off those the horizontal
[00:22:10.579]
and vertical tails
also helps reduce drag.
[00:22:13.059]
Drag which you've learned
about earlier losses thrust,
[00:22:16.439]
thrust before that propels the
airplane is usually provided
[00:22:19.769]
by Jet engines.
[00:22:20.889]
But if the airplane has too much
drag, it will need more thrust
[00:22:24.279]
for engine power however
when airplane is designed
[00:22:27.279]
for less drag like the
BWB less thrust is needed.
[00:22:32.009]
So what is this all mean?
[00:22:34.049]
Less thrust means
less fuel is needed.
[00:22:36.679]
>>: And less fuel means
less money to buy a ticket.
[00:22:40.129]
>> You got it.
[00:22:40.899]
Now, Windy you know
you said earlier
[00:22:42.069]
that BWB is just a concept airplane
[00:22:43.999]
so I guess that means it hasn't
[00:22:45.399]
[inaudible] yet.
[00:22:45.879]
>> Right, it would be too expensive
to build the full size BWB.
[00:22:48.549]
NASA going engineers come together
and design some scale models,
[00:22:53.489]
that way they can test it
before they build the full size
[00:22:56.139]
blended wind body.
[00:22:57.639]
>> Now you said some scale models,
is that mean that there is going
[00:23:00.759]
to be more than one
model of the BWB?
[00:23:03.249]
>>: Absolutely, if we only got one
model we couldn't collect enough
[00:23:06.429]
information so we build the
model that's approximately 1%
[00:23:10.119]
of the size of the BWB.
[00:23:11.989]
>> Hey let's do the math.
[00:23:15.219]
>> What would the 1% model
of the BWB look like?
[00:23:19.109]
Would it fit in your
classroom or in a shoe box?
[00:23:22.549]
>>: I know let's figure it out.
[00:23:24.819]
When you told this earlier that the
BWB will be two hundred forty seven
[00:23:28.459]
feet large, one hundred sixty feet
long and forty feet tall using
[00:23:34.249]
that a map let's take one percent
of each of those measurements.
[00:23:37.299]
>>: Okay, 1% of two forty
seven is two point four seven
[00:23:42.279]
or about two and half feet wide.
[00:23:45.339]
1% of one sixty is one point six
or about one and half feet long.
[00:23:51.569]
1% of forty is point four
or about half a top so ya,
[00:24:00.319]
1% model of the BWB should
definitely fit your class room,
[00:24:03.689]
right Wendy!
[00:24:04.809]
[Wendy:] That's right
and here it is.
[00:24:06.039]
As I said earlier building just one
scale model like this can give us
[00:24:10.319]
all the information we needed.
[00:24:11.989]
So we got a two percent, three
percent and a four percent model.
[00:24:15.669]
They all be tested here at NASA
[00:24:17.819]
[inaudible] and the Wind tunnels
[00:24:19.029]
to determine performance
and stability.
[00:24:21.299]
While Wind tunnel test can help us
predict how the BWB we will perform
[00:24:25.589]
it can't tell us how a
real pilot will be able
[00:24:27.879]
to petrol it in the air.
[00:24:29.619]
So NASA
[00:24:30.439]
[inaudible] is building another the
subs scaled model called the 'Low
[00:24:32.739]
Speed Vehicle' or LSV
and it will actually fly.
[00:24:36.169]
We will take our LSV
Wind tunnel predictions
[00:24:39.069]
and compare them to actual
[00:24:40.719]
[inaudible] data.
[00:24:41.489]
The flight test will take place
[00:24:42.709]
at NASA driving flight
research centre in California.
[00:24:46.039]
Engineers want to
learn how to control
[00:24:48.049]
and stabilize this new concept
airplane, so we fly safely.
[00:24:51.119]
In the Wind tunnel you
just can't simulate that.
[00:24:54.399]
LSV is about fourteen percent
the size of a full sized BWB.
[00:24:58.449]
Fourteen percent model of the BWB
is about thirty-five feet wide,
[00:25:03.759]
twenty-two feet long
and sixty high.
[00:25:07.149]
Remember in classroom
activity when you determine
[00:25:09.489]
that a grater prevalence surface
area produced greater drag,
[00:25:12.899]
let's look at the frontal view of
the fourteen percent BWB model.
[00:25:16.079]
To estimate the frontal surface
area all we need is the width,
[00:25:20.159]
the height and a little geometry.
[00:25:22.809]
First, we take the
frontal view and divide it
[00:25:25.059]
into parts chosen
geometric shapes like this.
[00:25:28.339]
Then we estimate the area
which geometric shape
[00:25:31.519]
and add them together to get
the total frontal surface area.
[00:25:35.189]
Next we combine the total
frontal surface area
[00:25:37.839]
with all the flight test
data with collective
[00:25:40.119]
and calculate the drag force
for this particular model.
[00:25:43.699]
>> We knew that the fly we
need a certain amount of
[00:25:46.179]
[inaudible] to become drag force.
[00:25:47.629]
>> Okay so figuring me out
the frontal surface area
[00:25:50.129]
of the fourteen percent
model of calculate drag
[00:25:53.159]
which then determines so
much thrust is needed.
[00:25:55.469]
>>: Right.
[00:25:56.219]
>>: Right, this is just
a concept airplane right,
[00:25:58.009]
I mean what if you want to
add something, may be you like
[00:26:01.549]
in observation that can talk.
[00:26:04.309]
>>: An observation
[00:26:04.979]
[inaudible] would definitely
increase the frontal surface area
[00:26:07.339]
[inaudible] which
would then increase
[00:26:09.789]
[inaudible], air become bad amount
of drag need to increase thrust
[00:26:13.039]
by adding more powerful engines.
[00:26:15.449]
>> No one that applies the go cart
[00:26:18.509]
[inaudible].
[00:26:18.509]
>> My final surface area was a
greater than his because I didn't
[00:26:23.609]
[inaudible] down into
aero-dynamic shape.
[00:26:25.789]
This greater frontal surface area
created more drag and I lost.
[00:26:30.339]
However, if I had more than less I
could have easily overcome the drag
[00:26:35.069]
and left
[00:26:35.589]
[inaudible] in the dust.
[00:26:36.339]
>> Now you know what,
[00:26:38.439]
[inaudible] come to that.
[00:26:39.239]
>> yeah.
[00:26:39.299]
>> You know we all
people made the connection
[00:26:42.749]
which mean aeronautical research
conducted your NASA and the math,
[00:26:45.409]
science and technology that you
do in your classes everyday.
[00:26:49.039]
>> Jennifer and I would love to
hear from you, your questions,
[00:26:51.689]
comments or suggestions.
[00:26:53.319]
So write us at NASA Connect, NASA
[00:26:55.719]
[inaudible] research center
mail stop four hundred.
[00:26:58.369]
[inaudible] Virginia two three six
eight one or send us an e-mail
[00:27:01.789]
[inaudible]
connect@edu.larc.naasa.gov.
[00:27:06.399]
>> Hey teacher if you would like
a video tape of this program
[00:27:09.019]
and we are accompanying
[00:27:10.509]
[inaudible] check out
the NASA connect website,
[00:27:13.489]
from our side if you link to
[00:27:14.899]
[inaudible] the NASA central
operation of resources
[00:27:18.099]
for educators or linked
[00:27:19.839]
to the NASA educator
resource centre network.
[00:27:22.269]
We would like to think everyone
who have make this episode
[00:27:25.649]
of NASA Connect possible,
especially Jackie Chan.
[00:27:29.139]
>> No, I'm thanking you
and thank you Bryan,
[00:27:31.879]
thank you NASA for inviting me.
[00:27:33.639]
I learned a lot of things because
when I was young I just only thing
[00:27:38.249]
I know was Martial Arts.
[00:27:41.989]
>> Taking
[00:27:42.719]
[inaudible] all kinds of things and
never know educating importantance.
[00:27:46.649]
Whenever I go, I will
support the children
[00:27:49.379]
because education is
very important, remember.
[00:27:51.559]
>> You heard it right from Jackie
Chan I will see you next time.
[00:27:55.469]
>> Yeah.
[00:27:55.999]
>> Well to understand flight
you must first under--
[00:27:59.639]
>> That's right, the
[00:28:01.909]
[inaudible] of--
[00:28:02.589]
>> Now, let's learn
how NASA researchers
[00:28:08.879]
or NASA engineers are
using geometry as they--
[00:28:13.549]
>> remember the
[00:28:15.549]
[inaudible]
[00:28:16.389]
>> I would to thank
[00:28:19.889]
[ Laughter ]
[00:28:20.119]
>> So get ready, get set
and flow and go flow--
[00:28:24.899]
>> [inaudible].
[00:28:24.899]