PROFESSOR: When we take complex things
and break them into smaller pieces,
we find out that we know a lot more about things
than we think.
[MUSIC PLAYING]
Now let's take this box ORCA I and can create damage
below the water line, which I've indicated right here.
[MUSIC PLAYING]
Now let's put ORCA I in the water and see what happens.
[MUSIC PLAYING]
[WATER FLOWING]
[FOG HORN]
The ORCA I sank due to the weight of the added water.
What if the ORCA I contained cargo or oil or even people?
Now let's take ORCA II and do the same thing.
[MUSIC PLAYING]
[WATER FLOWING]
[BELL RINGING]
So we can see that ORCA II did not sink,
although it is sitting at an angle towards the bow.
So why didn't ORCA II sink?
As easy as it sounds, this simple demonstration
is essential to design a huge, complex ships.
Ships that are responsible for carrying about 90%
of all our stuff.
As Naval architects, how do we design
ships carrying our stuff to make it into port safely and not
sink?
[MUSIC PLAYING]
Here have ORCA I and ORCA II from before.
Although ORCA I and ORCA II don't
engage in international trade, they
behave just as a 1,000 foot container ship would.
Now let's take a look in ORCA I. We can see that there's
nothing in it, it's just a box.
But if we look at ORCA II, we can
see that it's subdivided into these watertight compartments
by these transverse water type bulkheads.
Now what that means is that if we
were to damage the ship right here,
water would only flow into this compartment.
It would not going to this one, this one, or this one.
That would cause the ship to be angled or trimmed in the water,
but it would not cause the ship to sink completely.
We refer to ORCA II as being subdivided.
And we can see subdivision in many of these ships' plans.
It Is unclear when subdivision first
started being used in ships.
But accounts of 5th century Chinese trade ships
indicate that water would be able to enter
the vessel without sinking.
So let's find out why this happens.
Let's imagine a barge divided into 10 equal compartments.
One of them springs a leak from damage.
Since the ship is subdivided, only the first compartment
floods and the ship remains afloat,
protecting both its people and cargo.
Although the added water causes the ship to trim,
it still has enough buoyancy to return to port for repairs.
[MUSIC PLAYING]
Ships still sink though.
It's both expensive and impractical
to try to design the unsinkable ship,
especially when these ships will never
see that amount of damage.
That's why as naval architects we
use computer programs to help us out with subdivision.
Computers make it easy to simulate certain damage
cases in practically no time.
With different software, we can damage certain compartments
and see how the ship responds to it.
This gives a naval architect a good idea
of what parts to improve on the ship, if any.
So even though ships seem like these intricate, complex
things, they're really just based on principles
that we all already know.
[MUSIC PLAYING]