Yes

the late seventy's right off just

like you see there that could go right

back to enjoying the faculty here

rector of the great old

copy of the school itself that

is focused on various aspects of

helicopters as well.

Meter and lecture series.

Dr Sancha or thank you very much.

Good afternoon.

I appreciate all of you coming
to listen to this presentation.

Although I have my name here it's
really a work of a lot of students and

such engineers in the lab.

I brought my own Couric to clap
after every slide to be seen and

also Dr Weil I miss him.

So there's a lot of still young
young folks like this in it.

Folks are the ones that
make these things happen.

And I just want to make I
make sure my name is spelled

right that's my contribution
to haul this life.

So I'm going to be talking about the
following things you know I was not sure

nobody audience here would have so
I want to cover all the bases of.

Wind energy there than
focusing on just a my own and

there are feel you know something like a
backwater self Computational Fluid enemy.

So I'm going to talk about little bit
about how we got started in Maine energy

historically and talk about what
are some of the key technology areas.

Then I'll show you what's
going on in that area but

it turns out most of the interesting
things in this world are now happening

in the interface between two technologies.

You know if your biology chemistry is
all the many put them together bio

chemistry is a very exciting field
same thing in the wind energy.

It's a very highly multidisciplinary
interdisciplinary field so

show you some of the tools we use some
of the VIP sites where you could access

those type of information and also some of
the problems that are still remain to be

solved then I will try to conclude
it in I'm about an hour or so.

So.

We are going technology's very
very old in some respects

where it's been very widely known.

Almost five thousand years before
Christ in Egypt they were using

then to propose sailboats
in a people phone.

It was very painful to use.

Slaves and to propose from place to
place so they started using women energy

Chinese started using when
energy to pump water and

some through the mature form of
winter when I don't two hundred B.C..

Then the point here you'll hear
picture later on they started using

the narrative to grind corn and
other type of you know and grain.

So by Eleventh Century.

You know all throughout the Middle Middle
East they were already using in a winner.

Gee a great deal.

And you'll be almost think of your
service ten technology that went to

the Middle East in this at least case
in this case it was the opposite.

Crusaders went to fight a war in
the Middle East they discovered

that we managed the technology and
then they brought them all back to Europe.

You know.

Of course had a lot of problems.

You know not the least of it is we went to
a country of Netherlands was underwater.

You know sort of Us a lot of
interest in the doing the loops and

marshes and so forth.

So wind turbines became very popular
because there's a mentor when it's been

it could be used to pump the water and
drain the marshes and so forth.

Then when the people started
coming to United States.

The deuce bring brought a lot of
these technologies to America.

Had there was a dichotomy
because we had a lot of.

Lot of quo.

But we needed to pump the water turn
it into steam and produce electricity.

So it really became a hybrid system
where you use the vinter mine

to pump the water then you
hit a water using coal.

Then you start producing I knew any
kind of a steam power you know.

Different type of things.

But in one nine hundred thirty grew
a little bit difficult became popular.

There were many competing technologies for

making electricity economical you
know cost is obvious a driver.

So even though where are you and

gas prices went down in the winter buying
will become less popular then the oil and

gas prices go up you know they'll become
more popular this happened in the one nine

hundred eighty S. for example and
we had the energy crisis in this country.

Also most recently when the price
of oil and gas been tough.

So we had to really make a Konami
case no matter what you try to do.

But it's a clean renewable
sustainable energy source

therefore it's much more a much
more benefit by using this source

than an expendable in the fossil fuel and
some of the other technologies.

I promise to show you the picture from
putting out this is the this is what it is

basically they had what
you call a proto meal.

You know you could see sometimes
if you go to the river

there lever being dipping in the water
the water hits the bucket like.

Containers.

The neat spins.

It pumps the water so Persian a third
of why not do that with with the air.

Obviously didn't want the air
to hit one of the blades because

then they'll just go back and
forth they want to spin.

So they close part of it.

So the air will go through one side and
then turn the probe and

this is what the Persians were doing
almost a thousand years before Christ.

The then the designs became more and
more in a more more

complex vertical axis turbines in
the Basically these are a series of.

Sails like material but they've been hit
cities talk spinning this became popular.

That if you go to Europe.

You will see all of the Netherlands you
know different type of Macan isms for

unfurling and furling they've been
turbines turning them in the direction of

the vision and so forth.

But only when turbines
were using a technique

does a device called Drag basically
when the wind hits a very bluff body.

It pushes it backward which is the drag.

So that's part they were using
pelton wheel for example.

But when that happens in the back of this
block body you get a lot of what he sees

for patient flow.

So you're taking the very wind energy but
you're taking part of it and

throwing it away in
useless forms of energy.

So people started looking
at why not use a lift.

Look here's the other force which is the
force normal to the air that is flowing.

On Typically if you streamline the body
properly like an airplane wing or

a helicopter blade on a winter wind
blow it lift could be asked higher

As hundred to one.

And it does not have
all this excess losses.

So people started using
the lift force other

than the drag to turn the rotor
many rotors were made of fabric.

You know they would just take a fabric
put it on top of a sail like form.

They were quoted for
a different kind of a chemical so

that the air does not seek the leak from
the bottom side of the topside using it.

Just like that right.

Brothers through their first aircraft.

The.

It's very very rough surfaces than
they found their very draggy.

So it to have a new dragon when
you spin it through the air

you had to fight the viscosity friction.

Then they went to more smoother
forms new uniforms were using

the wooden wooden blades
highly polished surfaces.

Then they started using metal blades
because again you can make a very highly

polished metal plates and today of
course we use fiber fiber fiber glass

composites plastics and so for that may be
the only connection to what I'm saying in

this building which is the nanomaterials
building you know you could use and

the materials point to
this type of purposes.

So this is the drag devices.

And this is the mirror dynamic device.

So what happens is when the blade
is spinning forward and

the wind is going from
bottom to top in this case.

The Sultan vector is at an angle.

So it produces lift under drag

is a forward compound of lift this
what causes the inter-bank to spin.

So this is also used by some plans to
move in the flat or force it will spin.

When it lands.

When the helicopter loses power you
could use this technology to use what

you call an auto repair.

To land safely so
there's a lot of similarity.

So the important thing is to increase
the lift they do is the drag so

that the father directed
force is very high.

That's what produces the core.

So that's how when turbines work.

In the You Are So
you know there's no work has been done.

One time they still have lots of blades.

But as the technology improves they
realize you do not need all these bays and

if you had just a three or
four blades with the N.F.

lift you could produce
a sufficient amount of power.

So if you look at a management turbine
on the left side you have maybe later or

you know that's all it will be on
the other side you will see whether with

multiple blades metal structures
were disempowered so side by side.

So this is the end you the service
today meets the twenty first take my.

Century technology.

When turbines come a power house if
you put it on top of us a stray street

a small farm even a little
village of course the whole city.

You know you can still
stenciling them together.

When forms of course then becomes a lot
of technology issues you know that's

those are the type of things I will
talk about what is the problem with it.

Why don't we do this more often it's
some of the issues we'll talk about.

I was telling cost in that
it was recently in Europe.

I mean when we went through the channel
and came out of the other side as soon as

the train came out of the other side there
were tons of winter bans you know all over

the place so northern France became
one of my most popular places to visit

that plus cheese and good wine all those
would be good reasons and good to Europe.

So it was a wonderful place to go to.

So how big this wind turbines are they
are getting very very big Currently people

are talking about two point five megawatt
three megawatt even more if you look at

the diameter of those winter blinds
they'll be bigger than this and

up on the airplane.

Indeed they are becoming a problem because
if a paralegal Bishan authorities say.

If you use a radar at gaiety
airplanes hard to pick incoming

airplanes these things are in the way and

they're going to be you know become an
interference so there's a lot of issues.

People are struggling with they're
also worried that Smiley airplanes

can fly between this winter by and you'll
never detect them you know if they are for

example intruding into airspace.

So lots of issues like that are going
on interdisciplinary Haswell.

OK they would be no it's
because the typical damage

is like a hundred one hundred metre are so

vast a minimum it has to be a hundred
metre but you need some clearance.

Because there is a boundary layer
on the grown very low velocity.

So you need to have sufficiently
high altitude in order to make

these things right.

Maybe two hundred meter
hundred fifty meter.

That's the thing right.

So I'm going to talk about
some individual technologies.

You know that are very
important in Mynor GA

you like you know dynamics talk
a little bit about structures and

structural dynamics little bit
about multiple energy sources.

How do you hook them together.

The economics.

I sing.

Obviously we can do justice to all of
those so I will sometimes point some

pretty pictures and show you some
websites that could get more information.

But if you only work in the purely
area the game is done because we have

very good tools in all of these areas.

But the many important thing is where
the interface between this technology

is lot of work to be done.

How do you link.

Here we're going to mix code
with an economics model or

a stock children a mixed model or
an icing model.

If you go to Texas.

You know you won't believe it
on a hard day like this but

they get a lot of ice ice storms.

So when that happens the winter
winds have to be shut down sometimes

they may they even fit in and
they break the gear.

So for lots of into disability areas they
need to work on so I'm sure these pictures

were over and over again when they go from
one technology to all of the technology.

So let's get started with that.

Where do we get the data.

We're going to see everything was
collected from field data they will put

a window on a more meter you know on
the tunnel itself or maybe upstream of it.

They will have a talk meter or

some kind of a cart device to measure
the power then they will measure the bins

Peterson's power and share it with their
user community of course customers.

But they have been turbines for

a very very very uncertain they're
growing in different ways.

So it was a very noisy data.

You know it was very hard to use for
a good quality validation of data.

But people from all around the you could
put other sensors on the winter buy ins so

that you can also start monitoring
the health of the system little bit

like what you're already doing in call.

First Carson the sensors monitor your
electrics Pollock's electrical page.

All you.

You know in temperatures than this in
your little signal on your computer.

So you need to fix this.

People are now starting to use
that type of technologies.

So that the birds often break down so
that's a problem get heat.

You know they break down very often
maintenance you don't want to do it every

three months or a three thousand miles
you want to do it wouldn't even need it.

Also you want to improve
the product life by collecting data

changing the technology and
see what happens to it.

Finally you won't have a quality control.

The same device fits all the time you
know who to go and ask to fix it.

So those are the areas.

They spent a bunch have to last for

thirty years they say if you're a private
former It's like a buying a house you know

you were to borrow some money
raise capital by selling stocks.

Then you operate it then you sell it
to the customers including Georgia

power than you paid back
the bank the interest

you pay back the investors
a return on investment.

The best companies want
to keep as a profit.

You know so that's a big business.

So these things have to last a long time.

Fortunately for a computational
fluid dynamics books like me.

There is becoming a very good quality
been tunnel data is becoming available.

One day that is called the first six
rotor from the National Renewable

energy labs just to test one
hundred twenty by eighty hello very

very rigid new elasticities eight they
could control they are angled they can

control the speed they could take a really
good data probably worse when speed.

But they also put pressure
taps all over the blade to

make the formation of the pressure.

They put velocity probes at four or
five places they could measure velocities

full angle Artie's so tons of good
data then they gave a blind test

they would give us the data so
they were day said you compute it.

Then we'll give you the answers.

Of course our fortunes favors the food
supply as we had good workers you know.

So we got a good really good predictions.

So be very able to continue with our
development of safety methodologies

because the math data matched
fairly well with the calculations.

Say have these only the payment
of it it started in two thousand.

But as many as if you look at your
classical textbooks thermodynamics or

the hydrodynamics you heard of a period
where you hear about the fruit.

You have what rank gain in rank and
temperature bets.

You know these folks started
developing a disk based model

of a very suburban turbine but
it's a broader turbine or

a propeller doesn't matter they will come
up with a disk based model didn't worry

about the details of the blade they came
up with that approximate average thing.

Leaving room for German called glowered in
the between the wars the first world war

and second world war started working
in Germany with a scientist like panel.

So he died of the theory
called their element theory.

So these were the work courses for
the winter been development until

around two thousand when the computational
fluid in the mix came into play.

Actually reduced model has
a very simplistic view

it's been the air goes towards the wind
turbine the winter because the block here

of course is a bluff body.

So we ask ourselves flowing around it so

you decrease having been velocity quite
a bit by the time you reach the road and

this is where flows through the rotor disk
into the way it continues to slow down.

So by the time you reach
the fall break it's almost

twice that loss has taken place.

This is what's the picture gives.

Now be optimizing the blades you could
try to see how much energy is flowing

in how much energy is flowing out then
the difference is the energy you extract.

So this Martin says for
optimum performance.

You should slow down one
third of the velocity.

For example if you have a six me.

Person and
second win by the time he hits the road or

does the mean speech will be for
me to perception but

I mean here's the very big boom Europe or
second you know try to get all the air

out of it because you because a bluff
body hair will just go away from it.

If you don't slow down at all then
you'll just go right through it

you don't get any power.

So it turns out the maximum efficiency
you can expect from of intervention is

approximately sixty percent sixteen or
twenty seven.

This is called the bets limit.

So when I want our scientists come up with
some predictions we always test it against

its limit to see that it's
broken before we do that

we have winter away in school
point four nine point five.

You know is the efficiency to go
they'll be percent is a battle.

You know they try to
squeeze the last percent.

Because if you have a two megawatt turbine
one person of two megawatt is a lot of

lot of power twenty
thousand watts per second.

That you know that's a power.

You are getting but only one thirty
on the other hand you some or

it wouldn't mix because so it takes
a helicopter blade out of Winterburn blade

break it into segments and each segment
you compute the velocity the new compute

the lift and drag find out how
much is power directed multiply by

the radius that's the park sum up all
the elements that is the total power.

So this is a very easily done on a P.C.

You could even do on your i Pod if you
want to you know it's easy to program it.

There are good programs from University
of Illinois Obama campaign by Professor

silly called proper ID You can download it
executable if you want to play with this

National Renewable Energy Lab
has got a program called W.

people who've been for Been performance.

Again public domain National Renewable
Energy Lab also it's got another program

called the audience so that's a lot of
programs like this you could now download

or and design your own retirement if
that's what you want to do so this

is the lift to drag you find a forward
propensity for multiply by our that's the.

Work some up over all
the elements that's of it.

Words computational fluid
dynamics the other way.

Say someone to solve
the floor the entire blade.

So first thing they do is
generate a good out on the blade

use a three dimensional geometry
sort of go from good to ten.

Some people will do
the good the whole field.

You know including the blades the big
structure everything else you

know about a group we found it was very
expensive because it takes days sometimes

months of computer time to get an answer.

So what we do is we model one of
the details of the blade near the road or

once you go away.

We take what is their bodies left
is the VIX structure and the X.

Factor has kind of.

Started just like a propeller
big machine a propeller.

So you really want to model the wood
he says using a technical advantage in

technique track it.

It's like a mini tornado it
induces some to last a field.

You could analytically computer.

When you do this in the computer
time because quite reasonable.

You could do it in there
maybe a few hours to Lucian.

On today's clusters.

So we have a program called Georgia Tech
hybrid called bitches what we use in our

technology calculations here it seems
to work quite well this is by Prius

is turned up mine called Dr
funky party is now in Bangkok.

The yard changes you could see how much is

the torque hearing
are different in speeds.

Those dots are the experimental data the
pink line is the prediction simple road

work reasonably well.

You could also find the bending
moments of the route.

You could also do a power versus min speed
you know type of data you could do if you

took this point me take two to three
hours on a cluster Solar Week.

You could map the entire performance.

So if you this is a period or

Dynamix when I say we could
also look at the full field.

The Currently we have a project
with Arpaio we where Dr Bob and

Larry is trying to blow it.

From the teenage deflect the flow.

Anytime you turn the floor on action
reaction you're going to get extra lift.

So his theory is that you
could produce more power

approach the Brits limit better then you
know you've hit a pretty clean blade.

So Dr B. what I mean is working
on this particular area.

So these are some of
the simulations we have done.

Some of the research issues purely in
the food on the exterior are the flow goes

from laminar flow to turbulent
flow lamina means layer by layer

turbulent means big separate is current.

So some of you may have
seen it in your food and

mix classes laminar flow is good
because it's got a very low drag

turbulent flow is bad because of
rough surface you eat all the power.

It produced fighting
the drag on the blade.

So varied ways from laminate to
table it is called transitional So

one of the big areas we are working
on is the transmission model.

Unfortunately we are still using only
yappin like models which are steady flow

based models secondary I is turbulence.

You know how to how do these things mix
boundary layer mix with the outer flow.

When the flow separates styles.

What happens.

Nobilis is a big A here.

So you never group an all around the
country people are developing different

turbulence models to do these things.

If this is the way you know I would be
very happy to talk to you or better yet

introduce you to some of my students you
know they will give you good details but

these are some of the areas of the pure
prudent and makes that you can work on.

Really.

Well just not nice and

scary like an airplane in the rain
bit is rapidly very rapidly.

What you ate so there is a need
to transition these technologies

to unsteady flows on steady
mean flow problems model so

that it would work on so
we need to work on these type of areas.

So we are done up in Terminus models like
Dr maintenance group in Georgia Tech.

This is a lift versus pitch
angle is a top left corner.

Drag which is pitching with the top right.

Which you moment versus the angle
of attack of the pitch angle is

a bottom curve.

This is to show not be able
to model stall phenomena.

So we are beginning to use these type
of problems model in our studies.

If the.

If the ending is changing rapidly
because of the wind shifting

then you get a stall out of stall
stall out of style could happen.

This could this be call it a dynamic
stall you could not remain this model

without a computer courts are beginning
to produce the like before and

Sers but he said that he wouldn't
mix when he appears on a D.M.

you need to cut me to some other
area to get to even more benefits.

So the next examples I sure would be
structures and structural dynamics

why because people are talking about
very tall turbines like you talk about.

So the yawning motion of the turbine
the tower itself will become a problem.

If you support it on the on a on
a if it is for on off sure nobody

can go down to the seabed how people are
talking about tethering it to the seabed.

You know so that it's a becomes
a completely floating platform.

If you look at Siemens what they're trying
to do is they're trying to take four ships

they fly it move them together and
then they know put that in space and

becomes a floating platform then they have
their own little proper like devices that

stabilizes you know just like almost
like an oil rigs would do it.

So lots of unsteadiness comes
because of the energy body motion.

On top of it if you told the van that have
been hit submerged it becomes unsteady

birds hit the tower than
the tower starts moving in.

We have a lightning strikes you know
icing all kind of problems can occur.

So when this happens.

You cannot just depend on the pew here or
the mix C.F.D.

or the blade element theory of technology.

So what you need to do is hit with
something much more complex than this

very you get.

The operating conditions you trim
the rudder so that it produces the right

power timing simply means turning
the pitch of the blade to reduce or

increase the power yarning the power so
that it always faces when

changing the R.P.M. with some kind
of a electro mechanical brake so

that you don't work for speed in all
these things have to take place.

So you have their dynamics you
know dynamics power dynamics

power plant dynamics all
these things put together.

So now industries are trying to put
together very complex simulations

which will model all of this the driver
of course is the blade aerodynamics.

So that's where the C.F.P.
comes in it becomes a disturbance

that you put into the system and
see how does the system respond.

You could also have you know different
a rigid body responses he could also see

if we just disturb the system is going
to damp back the working position.

This would be very important in a sea
based system than a very comes and

hits the power base that's
established itself.

You know that becomes
a very important issue.

It turns out you need a structural
damping like a shock absorbers you need

our official dampers shock absorbers
with the springs and shock absorbers.

But you can also use the wood
then to make a damping

basically flap your hand down because of
this is the first that pushes it upwards.

So if you flap it this
is the ordinary damping

if that you wouldn't make damping becomes
negative for some reason because of

the stall effects then you have a real
problem then the whole thing will fail.

Not in the hours.

Not in minutes.

Not in the second sometimes no.

So you had to get a new system after that.

So people have found that when you have
a very high even speed like a fifty

meter per second.

You take apart the blades that means
not spin the minute happens it

becomes like an airplane.

You know then it started doing all
kind of bad things but I was taught.

It's oscillating the birds are isolating
the whole system can fail.

So this is an interface between
the neuro dynamics and structures.

That's in the area of grave
concern to the industry.

So they make good time and
then eventually some going to limit cycle.

So we need to be able to detect me and
be able to capture them properly.

How do you model it structurally
you could go to again

in round National Renewable Energy Lab and

get a program called Adams
the German programs other programs.

Or Georgia Tech in our group or join you
know space knitting There's a professor

but show he has felt a program called Di
more free for the asking the from him.

And we have other programs
government software

that could do this particular Dynamix
you can model doctors the blade but

also the hinges in
the joints the whole thing.

Now going the drive train
you know gears you name it.

You can put it of course the money
elements you add the more complex

the simulation becomes
That's the main thing.

So one of the research we
had that we're doing is

coupling our aerodynamic solvers to this
type of structural dynamics all over

then looking at the country
all devices on the blades

to damp out this oscillations if you look
at all in the airplane when you're flying

you'll see the flaps automatically moving
up are down sometimes the Iran is moving.

Yeah bricks.

You know spoilers are coming up and down
the pilot is not doing it you know he or

she is walking down the cabin
drinking your coffee.

Hopefully not a beer or

something else talking to you at
the computers does it automatically.

So there's a lot of interest in
putting these type of devices

automatically sense on the moon.

So we have a dollop ing it.

But if you know we have a thing or
using C. left is very very expensive.

You know it'll take base of time to do one
simulation where you put these devices is

very very hard to do so not be currently
do is this is an example of a device.

Read it back into the structural
dynamics iterate on it.

So then you know it's the ability to
think it and limit cycle solution.

This is called a loose coupling.

Do your dynamics.

Then pass it on to the to
the structural Dynamix.

You standard for Ally also that these
are not directly grouped together.

So if Di more changes you can put some
other path after their you first see if

he might see if I will see if it changes
because for some other software there.

On that approach is called tightly
coupled very every step you

simultaneously integrate the solid and

the food the equations of motion because
maybe the things are growing with time

you can be running multiple revolutions
here to see what's going on.

So we have also developed
a tightly coupled methodology

these things typically take one devolution
three hours on a eight processor

computer as they have more
processors as these technologies.

Get better.

We should be able to do much faster.

Get real time answers for
Hero elastic behavior or

any blades you know that
the industry wants to look at.

So we have done something for

some Yeah planes helicopters because
that's where the lot of data is available.

So some of our researchers
here have done I'm

sorry the axis is a universal
What it lacks is the left.

Now design like this is that evolution has
you go zero to three sixty zero to sixty.

So what you see is that you can
capture the peak to peak variation

the black line is the test data

the red line is the loosely coupled That
means once every revolution past the data.

Moon is tightly coupled that
means every time step you

simultaneously integrate solid and fluids

all atrociously are in the same graph
paper you could use the pick to pick.

No you can tell the designers
know these are the lords.

But your blade is going to pace.

Please make sure it's going to stand
that it's got a fatigue life for this.

So that type of information
they could use bother.

There are still no more
problems to be thoughtful.

Worse is a scratching the surface
stochastic loading of waves and

Vince need to be done.

You need to do it not for one minute not
for few revolutions but for a life cycle.

You know thirty years or
twenty years or so.

So it assimilated the look
at the Made life.

You have to get people life and so forth
to project what back need to invest in.

So there's a lot of research in this
area so tons of work to be done there.

So investors in this country
know Siemens G. Clipper they

are very much interested in this type
of technology and this technology.

I'll talk about is called hybrid systems
with multiple energy sources wind is not

blowing all the time they're part of you
will have to come up with some very for

combining different technologies.

So one of the very good that you
could freely download call a home or

home or
energy dot com It's a very best tool.

So it'll come up with a nice
bit of interface I'll show you.

But don't let the simplicity fool you.

You could put in a see if the data
means Peterson's power but

you don't need it offline
into the program.

You could put a man History Day
by day month by month or

your last name of in history.

You can put a four to one.

So you can put hydro power diesel electric

utility in my court when you
also put them all together.

And you can cook them up just
like in a CAD program or

a electrical engineering program and
like them are.

And then will come up with cost
seven cents per kilowatt hour and

you can do award if game say if this fails
if I turn to what's going to happen to

me you can ask me look at
the failure of a grade.

If this crude got hit
by a electrical strike.

What happens to the system could do this
so Homer is a very very powerful tool

that we sometimes use in
combination with the analysis.

You could put in daily variations
of when you can add water.

Pumping refrigeration.

Maybe you turn on the refrigerator
in the middle of the day.

Maybe one night you know and
then the Lord suddenly goes.

You can do those things.

So you can come by many different things.

There are tons of documents available
there's a big user group of A level.

So you could easily get
the very top people.

This is becoming almost like Google type
of you know Facebook of a group people

working with each other so
that you could have the best

interface would look very very simple
like if you can turn on different and

generators and
if you click on that symbol.

Then you can put in the information about
the turbine of wind speed versus power for

example you can connect them up

the do a small nation will
give you the answers for you.

So hybrid systems could be used

in combination with the aerodynamics
tools that I have just told you about.

The last year.

Yeah I think I'm going to talk about
is that to me because it gives

you also the sense in kilowatt hour.

You can do a cost economics analysis
of concision costs are apparently

well defined know there's a tons of data
that determines that our cost made cost.

To turbine cost you
know many things occur.

It's of a level.

So you can put them together the more
you can mark taking a question

cost maybe one million per megawatt.

Is what is the current cost offshore
to be much more expensive than that

then you say pay a one million I'm going
to do thirty percent borrow money.

Seventy percent I'm going to raise the
cost borrow money they're going to charge

me eight percent interest
because they're risky venture.

You're a venture capitalist
maybe even asking for

thirty percent return on investment.

So you come up with a return on investment
in these type of models will tell you that

it will make a buck or you're going
to go broke next day with versa.

So you can do projections of that nature.

So let me talk about the icing I sing or.

When we both fight to apply
most lights are so and

then we can pick from questions.

Icing is a very very important
thing that because of the ice

when when the ice problems
on the Winter been laid.

It becomes a chunk of solid body.

There goes your aerodynamics.

There goes your left lift is
what you're depending on for

producing power you get lots of drag so
that becomes failure.

Secondly because the ice is a bluff body.

It's got a lot of wood it is behind it.

Just like behind a truck.

You see those awesome
nations of one street here.

So those excited the blades than the birds
are doing crazy things vibration goes.

Secondly because ice may share.

You know maybe it's a danger to the tub or
maybe to the neighboring forms or

you know maybe a little cow that is this
you know be out in that bad weather.

Anyway so but.

They're doing it it will then go through
some by abrasions they may fail.

So lots of issues of this.

Unfortunately icing is a very slow
process and it takes sometimes minutes

hours to form a thin slice
of ice on a surface but

as you know then we know more
much faster one card links.

Six car lengths of travel solid
takes between the old enemies.

If you change the blade angle by
one degree by the time the bed

section travels to six meters or

so you wouldn't mix already settled
down because the ice is changing.

Before we can mark to simultaneously in
time because one is a slow process or

when it's a fast process.

So we have to couple all
of these things together.

So what we do in our group is as follows.

You take a clean rotor in this case
a winter by and they give you some wind

speeds they give your desired hub loops
in this case a power you want to achieve.

Then you work with our C have to code
maybe with a structural dynamics code

that can work together and
you just really strange phenomena.

Once you have it you take
the very last day feel

transformed into a boot fix Cornett
systems of the blade is standing fixed

the air is coming towards it then speed.

This is a bit of a blade.

Manual release ice
particles in front of it.

See where does it hit most of
the time it'll hit on the inside.

Just like bugs you know get on your
windshield the DO collect there as soon as

he had that information you can say OK I'm
collecting this much mass of water here

every second some up it's going to splash
all some US is going to flow whether

soap is in the going to the V.A. but
some of it will stick to the surface and

form a layer of ice in the next
layer of ice will form on top of it.

So we have to do a mass balance analysis
to do an energy balance analysis you

take a large chunks of time in the minutes
of time because it's a slow process.

So there is a program called blue
eyes theory because they wanted to

NASA Glinda says Center.

Used to be NASA Lewis but
Lewis was not a senator.

So they changed the name
to NASA glanders as center.

You may remember Senator Glenn.

So the program of the on the I
wasn't us that I should becomes

a sizable chunk you had to rebuild rebuild
the blade because the very cheapest

change because of the presence of this
chunk of ice repeat the whole process.

So this is becoming to do
the couples beginnings and

the interface between the fluid dynamics
between structural dynamics ice formation.

You could do it for
helicopter you could do it for you.

Aircraft.

Of course you could also do for

winter buying I think this
is going to be a big area.

You know given the fact that we're
going to be operating it in offshore in

quote climes in the Northern Europe
even Texas you know it's not immune

to these type of problems.

So we have done some validations we
have students in our group who quote

take a very simple to do you
know go to the simulation.

The blue line the use here
is the is the solid surface

the the blue dotted line
is the when the ice and

ice has formed is the red squares and
blue dotted line is the simulation.

This means you could think of it as after
one minute after three minutes after

a six minute.

One of the waves.

I do it in one shot.

I take a small steps three
times six times you can do it.

So this shows it works
very well in this case.

Sometimes it doesn't work.

Sometimes it works.

So we take a coffee break and
come back and

try something else with the forward work.

So we could we could also look at
the pressure feel using C.F.D.

the front part of the unified
because very blunt.

Your point has got a lot of drag in
front of your car you know it is

a high pressure drag.

So when that happens.

There goes your power.

So what happens is then we
could look at the forces.

Zero degree to tuna sixty degrees.

You can see what is happening to
the forces for example in the direct or

in this case the negative part of
the slowing down pressure drag is

torque is rising because of it.

You could even go through
Dealey route to tip and

see that it has happened VERY is
the biggest chunk of ice forming.

Of course you can heat it but
it's very expensive to heat.

You know been turbin blades so
helicopters or some other devices this

type of knowledge could be used to locally
put heating pads to heat the surface.

So as you say you get an interdisciplinary
feel that you could do lots of.

So in summary.

The turbine technologies
are very well developed for you.

Lots of jobs there lots of
problems problems to be

saw with I would say that the New York
piece is going to be solved.

So you are Dynamix is beginning to be
understood start till the next is being to

be understood the economics
models are known I.

Singh model so
no I did not talk about the noise.

Just like a helicopter ruler or
a fan or the blades have some thick

mist therefore they have a thickness
noise when they produce lift

they have to work picks passes
through your passes by you the noise.

They have are turning edge of Lake
structure this color turbulence noise

these noise becomes their computer records
that you could use to predict them

very fortunately in the sense
it's not a very very high.

You know fifty to sixty be very
quiet compared to the airplane or

a jet aircraft.

But even that swishing noise in
the very very slow roll low frequency.

That's bad things apparently
of the human body element so

for people of different colors
it's sometimes a psychoacoustics

there's another here you have you know
interest in things that thing works you

can go to the College of Liberal Arts and
get a degree or a problem.

Also people have found that the shadow
effect if you live next to a winter by in

the shadow drives people
crazy you know in that light.

So these are the areas where
you know you could work on so

I did not talk about it in
my mental impact in a birds.

Migratory pattern of the same
areas where you have a lot of men

between the mountains passages
is what the birds like

to fight through because they can
take advantage of the gust that and

carry through for
the day that's why in Northern California.

There's a lot of migratory birds and
how are you places like that.

So you have to be very sensitive to it or
it.

Sometimes when you put it on
a very valuable property.

Maybe because it's.

Indian in American Indian land for

example you know they have
a very important issues to them.

So you have to get their acceptance or

the noise even the most liberal of
you know Americans like in Boston.

They wouldn't want the winter when you
could put it anywhere as long as not

blocking their coastline.

You know that's what they want to do.

So the you have to fight
through all of these things.

So when you design a winter
when you had almost make a case

in front of a community.

Sure they cannot mix cost
benefit in minimal impact

then only when the banker
write a check on you or

you are you know to start selling those
takes the billion part of the area.

I teach a course called Winter of
interment technology forty eight

zero three.

It's publicly available all the class
moves all the tunes they mention here

are available their
Powerpoint slides their.

Videos of me but you have already seen
my face so you don't want to turn on

the radios and look at my pins but you can
certainly watch the lectures if you like.

So it's a very interesting when
you have your come a long way

from the time the Persians
started building these devices.

Many of the models have
evolved significantly.

The fluid dynamics in the missis is
the transmission turbulence how do you

model the and steady flow still there.

So our group will still continue to work
on it but the moon interesting in areas.

When you talk interfacing one
discipline with other disciplines and

you start doing active or a country.

You know elastic modeling icing noise for
this is that it can be lots of work to be

done so I wish you all the best if
you want to work this into Syria and

I'll be very happy to
take a few questions.

I'm going to stop at this time.

Thank you very much thank.

Histories.

You.

Well that

actuator disk theory is independent
of the Winspear it's a.

Low speed income possible flow
the infinite number of late.

It's got a lot of assumptions in there.

So it will walk away from zero meter per
second to fifty sixty you know it doesn't

matter because the mock them but
not take into consideration.

So it'll soon a theoretically the maximum
limit is you floor down by one third

spoke to me in a person can then.

You had slowed down to thirty
four meter where they would be to

the printer by going to
seventy meters per second.

We had the power becomes
a proportional to the mass flow

rate which is going to be lost in that.

And the kinetic energy of
the air one half of rescore air.

So the power becomes proportional
to be cubed times the disc area.

So the bigger here is better but faster
wind is even better because the V. Q So

some countries you know they may not have
a high wind event when they can park but

maybe there's a digest at a four meter
per second wind meter per second.

Not enough to produce power.

So we're hoping some of these devices like
the circulation control may be able to

produce a little bit of power out of it so

that we can still have a problem
proximate but slim and

nobody give you a different answer than
you expected a different direction but

it's worked for all the wind turbines
the theoretical limit I would say.

As for.

This.

But.

Yes.

Yeah.

OK.

I think it won't be
the best place to put put

it in there because the vehicle
behind the vehicle seen on again and

over six to ten quarter lengths of
the car length for example it's gone.

So unlit Mr Simple lot of it does have
a lot of energy in the vehicle for it.

So if you.

Capture it would be
it'll be able to do it.

Plus it's sort of a maverick.

You know it does not spread.

Since you don't want to put these
devices on the highway yet.

You know we don't want you know that's
a difficult problem but in the community.

You know because of
the clearance available.

One may be able to put a small winter buy
in and capture the capture of the energy.

It's again is going to be neutered B.B.Q.
I supply our square you cannot put

a very large turbine and I've been here
because of the skyscrapers in others

they act as an office so they're going to
slow down and there's a boundary in there.

So you're not going to
get a lot of power but

you can get some power
out of it in a possible.

A fiscally viable but

it will make you feel good in the end of
the day off with a very important place.

Looking.

Look at the various
anywhere from three cents

per kilowatt hour to say twenty
cents per kilowatt hour.

OK.
Depending on how how much and

when the summer a little in that region.

How big a turbine you build to repeat
the bigger the better you know

the larger diameter orders they
can easily approach this limit at

least fifty percent
efficiency smaller turbines.

They're not as efficient.

Plus they're economy of
scale is not in their favor.

So they'll be very expensive but
it could us only

use this weather this technology could
also be used for hydro turbines.

We may be able to dip a little turbine in

the water in the Chattahoochee
then listen to the Braves game.

You know.
And

they've done thirty off the scent of the
Georgia Tech revolver something like that.

So people are looking at low head
her brains and hydro turbines.

It may be possible to power
those the boys on the other.

Maybe he's interested
in putting listening.

So you figure some of the capture
that under current of water to

catch a power not something to sing.

Yes yes.

You acknowledge that.

Right off.

Today's technology.

You need some subsidy like
in Georgia Power of the buy

certain percentage of renewable
energy from a winter of an operator

because there's also a carbon
offset in on the things.

So right now all of the people feeling
is it's not competent to give it

nuclear nuclear power before.

It's very competent to give it the fuel.

You know like you.
Howie.

The import all the oil.

So by the time it gets to while
you've got very very expensive.

They're almost you know when you pull
putting you would say if you could prevent

or been there on the other hand when
you have an abundance of other sources.

You would need a subsidy to be.

OK.

The reason is the vendée is
not growing all the time so

the such a thing called a capacity factor.

So one could thirty percent of
the time you get the right.

Minute.

When it is too low and you know it just
not enough power there when it's too high

you have to turn off the rotor because
the blades are going to get damaged.

So we have a very narrow window and
that's the primary limitation.

His base.

Great.

OK.

Yes yes.

You agree.

Right.

That.

Yet thanks for
letting us know that senior V.P.

from clip earlier Dr I mean McHale He said
Georgia graduate he was my classmate.

He took the high road became a senior V.P.
I'm still teaching classes here.

So I know you know where
the big bucks are.

Thank you.

T..