The issue still remains how to clean it up and it will involve a little bit of cutting edge technology but also a whole lot of ancient physics - and I'll even show you how to duplicate it in your house.
The solutions to the Gulf Oil spill have ranged from kooky (set the thing on fire) to well-meaning, but hardly enough (panty-hose stuffed with hair clippings) and finally back to that big old thing called the Deepwater Enterprise with a containment dome over the pipe spewing forth the oil. This is in addition to the chemical dispersants, oil skimmers and booms they have already tried, none of which have made bioremediation experts happy, since the detergents to clean a spill of this size would be more harmful than the oil itself.
Given enough time, nature will take care of the oil spill - oil is a biological product and can be degraded by microbes - but it will never happen unless the oil is stopped.
Exit nature, enter science.
Deepwater Enterprise containment dome stands as high as a four-story building. Credit: Petty Officer 3rd Class Patrick Kelley, U.S. Coast Guard
Now, if you're reading this article you are already pretty smart so you may be thinking the cleanup would be thanks to Bernoulli, but if we go even farther it is thanks to Newton - I can make anything about Newton much like Neil Shubin can make anything about fish.
Bernoulli is famous in fluid dynamics and being in this article will only make him moreso. His best known concept was that as the speed of a moving fluid increases, the pressure within it will decrease. Counter-intuitive, I agree, but welcome to science. It is also incorrectly applied a lot, like science books stating that Bernoulli is why planes fly (errr, Newton again. See?).
How the containment dome works - old school physics
There are a few issues involved in getting this containment device to actually contain oil. Getting it to 'seat' properly will be key to getting everything else to work and that is an engineering issue. They have little robots that will handle that and we know how little robots work - I have one that cleans my rug - so I won't go into it here.
The second issue is a chemistry one and the third issue is physics.
Once the containment dome is in place and everyone cheers at how great robots are, Newton will do the actual work. Let's explain pressure:
If you don't recall specifically, common sense tells you pressure is the average force/area of a fluid and its container but its behavior in fluids is why Bernoulli comes into play. In this case our fluid is the oil gushing out into an otherwise perfectly-functioning ecosystem - an ecosystem we would like to not ruin using a big vacuum cleaner or harsh chemicals. In order for pressure to help the container needs to have walls and that is what the containment dome is; artificial walls to create pressure.
The molecules of the oil will bounce off the walls of the containment, thereby changing their velocity and this change of velocity, says Newton's Second Law, comes from the action of the wall on the molecule. Newton's Third Law says the oil molecules exert an equal and opposite force on the wall.
At 5,000 feet beneath the Gulf the pressure is even greater because water is heavy ("a pint a pound the world around!") (1) so the job should be easier. But it's never that simple thanks to pesky issues like chemistry.
Halliburton, BP and President Barack Obama are all taking turns blaming each other but the plain fact is drilling has risks and one of those has been well-documented, to such an extent that 15 years ago it would never have been tried: ice-like crystals called methane hydrates. And they are mucking up the process here. Over the weekend these hydrates filled the top of the 98-ton containment dome, making it begin to float. Obviously that can happen in the pipe also.
The solution? It may be that more heat is needed or even just a bigger . At 5,000 feet the best option would seem to be pumping warm seawater to the space between the drill pipe, where the oil would flow to the ship, and the outer pipe. That's a technology issue, of course, and BP seems to be throwing everything at the problem. With 5,000 barrels of crude oil a day coming into the Gulf all options are available.
In the meantime,the new drilling push in the Arctic Ocean that President Barack Obama authorized to begin next month may stay a future project until the hydrates issue is better resolved.
Amaze your family with your knowledge of pressure and Newton!
Materials: A shower with a shower curtain. A towel.(2)
Get in the shower and close the curtain. Face the curtain and spin the towel and observe where the curtain moves inwards. The strongest pull is in the center of your spinning towel but if the inward pull was from the Bernoulli effect, then the pull would be strongest at the far end of the towel, where the air is moving the fastest. Instead, the strongest pull is in the center?
Spinning the towel causes the air inside the shower to spin as well. The spinning air moves outwards and as the air moves outwards, there is less air pressure left in the center. Surrounding air is pushed in towards this low pressure area, and so is the shower curtain.
NOTES:
(1) If you did the quick math you just realized that the same pressure should have caused us to explode while I wrote you and you read this; we have 100,000 Newtons per square meter of force due to air pressure on us right now. But the pressure of the fluids inside our body (blood, air, alcohol) equals the pressure from the atmosphere so here is no net force inward.
But diving in the ocean is another matter and the weight of the water can kill you. This is why deep-see divers use high-pressure oxygen tanks. That way the air they they breathe is about the same pressure as the water pushing inward on their lungs.
(2) More science experiments at Nicholas Academy
Comments