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Hello my name is Molly White. I grew up in Iowa and I went to Iowa State to get
my Aerospace Engineering undergraduate degree.
During my undergraduate
experience I came down to Johnson Space Center to have a co-op
and I worked several co-op tours down here
and once i finally graduated they offered me a full-time job to work down
at Johnson Space Center here in Houston Texas. And I came down here to work
on the current program that I work on which is Orion.
I work Orion Aerothermodynamics.
What that is as we're concerned with the heating rates to the exterior of the vehicle.
We want to make sure that the crew is protected from the high temperatures
that are around that capsule as it reenters through the atmosphere.
Orion is significantly different from any vehicle we've ever flown before.
For instance Orion is going to be reentering at
over twenty five thousand miles per hour
whereas the space shuttle reentered at only seventeen thousand miles per hour.
That's a significant difference in speed which translates into it even more
difference in kinetic energy
and that kinetic energy is what we have to dissipate
in order to lend our vehicle. So this uh... paper right here that we have
taped together into a cone is the actual shape of the Apollo vehicle.
On the
drawing here you can see that the different features on Apollo called
out such as the window
a tower and we also have the instrumentation where they took flight
measurements. Some of them are circled here in red but they're called out all around
the vehicle. so you can see the apollo was a much different shape from
Orion in the fact that this cone angle is at thirty three degrees and
we have a full cone with a tip on it. For Orion
were a truncated cone
and we're angled at thirty degrees. So this thirty degree backshell angle compared
to thirty three degrees backshell angle changes our heating significantly.
Orion overall will be hotter on this entire conical section compared to
Apollo. Also having this truncated cone compared to a Apollo changes how our
flow field comes around the vehicle and so that will change
different components and different heating. The reason that we use a
combination of both are computational predictions, our wind tunnel testing and
our flight testing
is because each one of those three has its own pros and cons. Flight testing is
obviously ideal because you're flying the real vehicle through its actual
environments and taking measurements on it and making sure that it performs
as it should,
however flight testing is extremely expensive and costly and takes a long
amount of time.
So to get away from flight testing we use both our computational predictions
and our wind tunnel testing. Both of these are a lot faster to do and a lot cheaper.
Our computational predictions are the fastest because we can just do those
on our computers
here in our offices but obviously those are taking a models and theories
into them and we need to make sure that those are validated and that they
accurately represent reality.
So to do that we compare to wind tunnel test data.
And wind tunnel test data gives us a scaled size vehicle in a simulated environment
then we can compare our computational tools to, to validate them.
We can't simulate all of our flight conditions in our wind tunnels and so
that's why it's still necessary to have that last component of flight testing
but until we get to that phase we can do our computational predictions and our wind tunnel
the testing in our design phases of our vehicle.