How big can a ship get?

[broberfett]

Suppose a bunch of Engineers and ship construction specialists got together and wanted to build a super huge ship and they can build it as big as they can build it with our technology. The ship is for the deep ocean and can have a huge depth to the keel of the ship too, so it doesn't have to worry about ever entering shallow waters.

 

[USS KG5]

Your ship could be as big as you like, there is no logical limit on it.

As long as it has sufficient bouyancy to support its weight the ship will float.

The main problem would be it was bluddy useless.

 

[Johnny Rico]

Isn't bouyancy tied to the mass and density of water underneath of the vessel? In other words, the water beneath a vessel has to be deep enough to support the mass of the vessel.

Most of the time, this isn't a problem. But in shallow waters and perhaps in gas bubble explosions that reduces the density of the water and any size vessel would sink if caught in such circumstances.

I'n fact, some scientist attribut this phenomenon to some of the mysterious ship disappearances in the Bermuda Triangle.

 

[FordSVT]

http://www.freedomship.com/

At this point it's basically a pipe dream for the developers of this ten year old project, but I can't imagine any practical floating object designed to move that would be larger than something like this.

 

[anti-matter]

^I agree after watching the pitch on the discovery channel ... a big target full of rich people.

 

[USS KG5]

Johnny Rico said:
Isn't bouyancy tied to the mass and density of water underneath of the vessel? In other words, the water beneath a vessel has to be deep enough to support the mass of the vessel.

Theres a pretty good explanation on Wikipedia here. that explains it. The depth does not matter as much as even if the ship is scraping the bottom then it is displacing water. The problem becomes when the water becomes less dense than the mass of the ship.

Most of the time, this isn't a problem. But in shallow waters and perhaps in gas bubble explosions that reduces the density of the water and any size vessel would sink if caught in such circumstances.

I think the theory is that gas bubbles from underwater volcano activity float up and obviously if they hit a hip then they destroy its bouyancy (as the gasses are less dense than the mass of the ship) and the ship will sink.

It is an interesting theory if true, though a larger ship would be less vulnerable as the bubble would probably only cover a small portion of the ship, just giving it a little bump.

 

[Timo]

One might wish to use a floating structure for example to span the Gibraltar straits. Less ecologic impact than from a solid dam, if you just want to tap into the energy of the currents flowing through. Possibly easier to do than a bridge, and more resistant to damage, if you just want a rail connection and possibly a highway. Combine the two, and make the thing a major harbor, industrial park and airport at the same time, then expand to turn the outer areas into holiday resorts. Float in more segments as needed, or construct more there and tow them to various parts of the Mediterranean to expand the coastal cities.

The structure could span something like 20X20 kilometers at first, three-four times the size of port of Rotterdam; provide its own power; and connect Europe and Africa, without necessarily being an eyesore or an ecodisaster.

After that, it's only a short hop to a Trantor/Coruscant setup where the oceans are covered rather than dried when extra surface area is desired. The life beneath might survive despite the substitution of an artificial sun.

Megastructures like that might thrive better over key bodies of water than over dry land, mainly because of the ease of movement of massive components, and the availability of power and water.

As for a floating construct that behaves more or less like a ship, Larry Niven's Ringworld had some oceans big enough that it was worthwhile for the locals to build floating islands, hundreds of kilometers per side, for conquering strange new lands.

Timo Saloniemi

 

[USS KG5]

Might be a bit impractical across the Straits of Gibraltar, a lot of big shipping goes through there and if you only left small gaps you would have dozens of collisions, especially considering the number of incompetently handled pleasure boats and Yachts you would be dealing with.

 

[Timo]

That'd be more or less the point, I'd think. The whole thing would be a vast drive-through harbor, massively filtering the traffic that goes through the straits. It might be beneficial to swap ships at that juncture anyway, and operate a different type of fleet in the Med than out on the Atlantic.

Eco-friendly, too, perhaps: greener ships could be built for the Med, incapable of crossing oceans but optimized for the sort of trans-Med bulk traffic that the megaship itself can't handle.

The passages for pleasure boats could easily be a kilometer wide, carefully managed, perfectly calm and covered by a sunroof...

Timo Saloniemi

 

[USS KG5]

Timo said:
That'd be more or less the point, I'd think. The whole thing would be a vast drive-through harbor, massively filtering the traffic that goes through the straits. It might be beneficial to swap ships at that juncture anyway, and operate a different type of fleet in the Med than out on the Atlantic.

But surely the whole point of the Suez canal was so big ships could go all the way from the Atlantic to the Far East in one trip - I doubt anyone would be keen to unload and re-load ships (a time consuming and expensive process) just for eco-friendly reasons.

I'm going a bit OTT in criticising your example - I actually agree that large offshore structures that float for harnessing tidal energy, for example, is probably a good way forward in renewable energy sources.

The problem so far is that the test stations have all been smashed up in storms here in England - they have not found a way of building something tough enough to ride out storms on the English coast.

 

[Timo]

The Straits would be good in the sense that the structure would be riding out storms as a secondary feature only; some of those powerplants you mention were placed in the harm's way as a primary means of gathering wave energy from regularly bad weather... And many tidal powerplants enjoy advantages over those offshore assemblies because they capture the tide at some sort of an inlet or estuary, being firmly anchored to the shores. An initial "floating dam" across the Gibraltar could be as short as 13 km, with two good shore anchorpoints and, assuming the rail link were an initial feature as well, a substantially more massive structure.

Of course, an underwater powerplant would be the most weatherproof way to tap the Gibraltar currents. But a traffic node that deliberately blocked shipping from the Mediterranean could be defensible exactly because it does that, for econopolitical reasons. Mare nostrum and all that.

Timo Saloniemi

 

[USS KG5]

Timo said:
The Straits would be good in the sense that the structure would be riding out storms as a secondary feature only; some of those powerplants you mention were placed in the harm's way as a primary means of gathering wave energy from regularly bad weather...

Sadly its always the problem with renwables, wind doesn't work when it isn't windy, solar doesn't work when it isn't sunny. The number of different technologies needed is pretty large, personally I'm waiting for a car that equals the performance of its petrol/diesel counterparts in all respects but that is eco friendly.

Lets face it if an eco-friendly engine was just another choice (when I brought my car I chose 2.0 diesel over 2.0 petrol because of economy) we would all buy eco-friendly cars.

And many tidal powerplants enjoy advantages over those offshore assemblies because they capture the tide at some sort of an inlet or estuary, being firmly anchored to the shores. An initial "floating dam" across the Gibraltar could be as short as 13 km, with two good shore anchorpoints and, assuming the rail link were an initial feature as well, a substantially more massive structure.

I think it might well be a good thing if it could supply all of Gibraltar's energy, the issue would be how many power stations of other types could you build for the money?

Of course, an underwater powerplant would be the most weatherproof way to tap the Gibraltar currents. But a traffic node that deliberately blocked shipping from the Mediterranean could be defensible exactly because it does that, for econopolitical reasons. Mare nostrum and all that.

I'll save geopolitics until I've eaten something!