A series to bring my thoughts on earth science up to date

I have been asking about volcanoes lately. …

Volcanoes and Fluid hammer

Water hammer is associated with the noisy plumbing characteristics of old houses. And old houses tend to have leaky taps. This is because old taps wear away and or form lime deposits on the seals and or both, the lime causing uneven erosion.

When a tap is closed the rate of water through put changes from several gallons a minute (overall potential in all taps) to something like half a pint every three or four hours (for pretty obvious) dripping taps.

After a short period of slowing down in the pipes the water settles down to the near steady drain the system has got used to. This in all probability becomes the house's harmonic. The internal backflow rate in the eddy set up between flushing and dripping is, nominally:

0.125 gallons per 4 hours (240 min) = 0.0005 gallons per minute; as opposed to 4 gallons a minute.
It's possible to work out the size of the pipe work but most people could guess as they use 1/2 for sinks and toilet cisterns and 3/4 for baths. All you need do is measure the approximate lengths of the floors to guess pipe runs, bearing in mind they will tend to take direct routes from the mains to the main distribution points -boilers etc.
I've ignored central heating.

0.0005 of 1 gallon is quarter of 4 gallons so the ratio of flow from full on to almost fully off is some 0.0001. That's about one ten thousandth of the potential.

Now apply it to a volcanic eruption.

We don't know the potential discharge of a volcano but the worst eruptions are pretty dramatic and the ash cloud can be fairly well guestimated from data collection points, satellite film and computer models. We can guess the approximate discharge of a caldera when the main vent is sealed form pretty much hands on measurements.

So we can gauge an approximate comparison. Let us assume the major volcanic eruptions from time to time are nearly maxed out and that vents provide 0.0001 of the emission that is possible. We don't know what is being lost to underground streams (if any) or is being added to, by heavy rain (which is common with massive eruptions.)

So it all very much a Mind Game.

Volcanic vents are blocked by the deposition of newly formed rock. It comes from the gas/water/debris mix or just from mass surges of molten matrix. There must be quite some oscillation going on when the caldera is open. I wonder if anyone has postulated Reynolds Numbers for that.

When it is finally slowed from its seiche to a magma hammer, the periodicity is now roughly what the constant wear and tear of volcanic formation created. And any changes in the Almost Stillness creates the sound reflected. (Because the opening is no longer acting as an Helmholtz resonator) the harmonic is occasionally (more often than previously) exactly that of the chamber.

When that happens or when the weather changes the magma can heat up in the vibration. (Infrasound used in jewellery baths etc can cause the oils used in them to get very warm.)

But the weather has to be just so in a variety of places at just the right distance to be ducted to the centre of the mountain.

Then kaboom!

Or not as the case may be.
Whatever the likelihood or unlikelihood, I know I can write it more clearly than that. And in the years to come you may see me do so till it bores you to tears.

The Reynolds number of fluid flow is a comparison of resistances to the flow. The main protagonists are the size of the obstruction (or diameter of the pipe) and the viscosity of the fluid.

For aircraft design the viscosity of air is 13 times less than water at ambient temperatures at sea level. This is a nonsense as planes don't fly at ambient temperatures and seldom at sea level.

For magma, the chamber size is constantly changing and the plasticity of the magma varies within the column at any one time and with the weather all the time.

But if people can work on aircraft fluid flows, what's the problem?
The key to the fluid flow velocities is much the same sort of deduction. If such is worth knowing for any reason.
I have not had a chance to think about that aspect yet.
And anyway, it is hyperbole wrapped up in day dreams about hypotheses built on what-ifs that I'm not sure of.


3 thoughts on “A series to bring my thoughts on earth science up to date

  1. Germany is to switch off all its nuclear reactors.That news just came through today. (some time back but commented on immediately.) I couldn't leave that without comment.When the world builds nuclear reactors in the hearts of its largest cities and puts them on the hills where the world's leaders live, we can be pretty sure that that will be the time we can be sure that nuclear reactors are safe.What is Germany to do?Even Iran and Iraq wanted nuclear power. They may want them to produce nuclear weapons. If Israel can have nuclear weapons why not less aggressive and more responsible governments? OTOH, it may be they are looking to the future when the oil runs out. Oil should be conserved for mobile use where a stable furnace the size of an electricity generator for a large city can use alternative power supplies.Germany has wind farms, coal seams and water generators. These things have their own unique problems. Coal produces fall out that can cause tuberculoses. Coal miners all die of ling disease. Cancers spread around them.Are they safer than nuclear energy?Wind farms don't work 24/7. That is why we don't use them. If we wish to convert estuaries into giant turbines, we still only get the power on the tide. It may be an immense resource but it devastates a valuable location, causes species extinction and once again, isn't 24/7.In Britain, we no longer wear the clothing appropriate to the weather. We expect the building we use to be heated to temperatures where T-shirts are all you need. The vast flocks of sheep that once clothed the northern world have been relegated to lagging roof lofts. Farmers can not make money producing wool. And the varieties of wool producing sheep we once had are no longer bred.Are we to go back to the days when everyone wore two or three sweaters indoors?Margaret Thatcher's government shut down mines because of political needs. She needed to deal with miners unions to stop them from using the threat of strikes to close the country. She wasn't interested in the future. She wasn't interested in the diseases the miners were suffering. And she wasn't interested in the damage that nuclear furnaces pose.There is a limit to how efficient a nuclear furnace can be. If you push more power out of the fuel rods than about 2 per cent of its capabilities, the cores of the furnaces tend to get polluted. A polluted core needs to be replaced and there is a limit to how efficient that becomes. There is now way to unpollute a nuclear core. It can never be used again. The graphite is not going to find its way into pencils and car tyres, it isn't going to be burnt to make concrete.You can't even bury it in the local council tip. It has to secure to time indefinite, buried in an accessible compound that no one will interfere with, not even to build on. It can't go into deep mines in case it pollutes the water. It has to be encased. And the casing must never fracture.Or you can dump it in the deep blue sea. That is what the British Government does.The Thatcher Government had the nuclear industry take up the slack that the miner's strike of the 1980's caused. Nobody has been told what damage that did to the cores of the nuclear furnaces. We do know what happened to Japan's furnaces. The tide came in and the fire went out. The cores melted and the whole shooting shebang is now reduced to rubble and slag.The British Government takes all Japan's nuclear waste.

  2. And finally:Nothing changes, does it?Everybody knows the skies are loaded everybody rolls as the waves are tossed.Everybody knows that the peace is over, that the sons of the fathers lost.Everybody knows how things are fixed; the poor get shafted and the rich stay rich.That's politics.Everybody knows.Everybody knows that the banks are thieving.Everybody knows the cartel lied.Everybody has the stinking feeling that the hopes of their fathers died.Everybody knows, everybody knows, that's how it goes.Everybody knows, everybody knows, everybody knows, everybody knows.Every body knows they really love us; that they would never lie to you.Everybody knows how they've been faithful except for the treachery they do.Everybody knows that they are discreet; all the heads of state they have to meet without their clothes.Everybody knows.

  3. Generating electricity with river and sea water.{This one might replace nuclear fuels}Stanford researchers have developed a battery that takes advantage of the difference in salinity between freshwater and seawater to produce electricity.Anywhere freshwater enters the sea, such as river mouths or estuaries, could be potential sites for a power plant using such a battery the limiting factor is the amount of freshwater available. The process could have little environmental impact.The battery is filled with freshwater and a small electric current is applied to charge it up. The freshwater is replaced with seawater increasing the electrical potential between the electrodes. The voltage depends on the concentration of the sodium and chlorine ions. You charge at low voltage in freshwater, then discharge at high voltage in sea water.Once discharged, the cycle can begin again. The key is changing the electrolyte. The battery could become 85 percent efficient with positive electrodes of nanorods of manganese dioxide and after finding a good material for the negative electrode. The water does not have to be extremely clean, storm runoff and foul water might be useable.A power plant operating with 50 cubic meters of freshwater per second could produce up to 100 megawatts of power, according to the team's calculations. That would be enough to provide electricity for about 100,000 households.Previous research has used the salinity contrast between freshwater and seawater to produce electricity with osmosis. Funding for this research came from King Abdullah University of Science and Technology (KAUST) and the U.S. Department of Energy.http://news.stanford.edu/{I find it difficult to believe that the charging rate in fresh water will be as cheap as it would be in brine. There is no such thing as a free lunch. Then again anyone could subsist on the free lunches supplied at an estuary. They are the richest food sources on the planet.It would be a pity to upset the ecology. Once the road through Conway was given to the people outside Conway the people of Conway were forced to lose their natural environment of mud flats so the community could have a marina. But the locals already had a marina, the River Conway estuary.So seeing how that went, you can see who are going to put the real money into developing environmental awareness. The same people who want to sell marina parking places for rich boat owners as somewhere to park their holiday homes 48 weeks in the year.Since everyone lives on an estuary if they live in a city that is older than the motor car, the potential is to destroy every estuarine environment in Britain. Purely for the local economy of course.Let's be positive. Using foul water would be a good thing if maximum efficiency was gained by first cleaning the water with filters. If river mussel beds could be used to do that, five miles or so of rich agricultural land could be given over to cleansing the foul water produced and discharged 5 miles down hill of every town using the appliance.Or maybe salt flats could be exterminated as they are already on the down hill side of cities?Besides which, the big problem is that nobody wants to be the first in the water. The pioneers always pay the most, get saddled with the least efficient plant and have to sell their stock to the financiers who waited for the inevitable.Having said that, I'd like a government to go ahead with an experimental plant. Somewhere else.}

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s