Difference between revisions of "Design Features"
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* Rationale: minimize interactions with the waves. | * Rationale: minimize interactions with the waves. | ||
* Implications: Floating vessel derive their stable position on the water from the fact that moving them up and down changes the volume of displaced water. If there is little waterplane area, this coupling is weak. This means the waves will have relatively little effect. On the other hand, the total flotation has to come from somewhere; as can be seen from any of the examples, this implies that the flotation is located somewhere below the waterline. This necessarily implies a medium to high draft, which has significant drawbacks (see: Design requirements/incrementalism/draft). Roll-stability can derive from any source; through the use of very deepb allast (FLIP, Spar), or wide footprint (semi-sub), or a combination of both (clubstead) | * Implications: Floating vessel derive their stable position on the water from the fact that moving them up and down changes the volume of displaced water. If there is little waterplane area, this coupling is weak. This means the waves will have relatively little effect. On the other hand, the total flotation has to come from somewhere; as can be seen from any of the examples, this implies that the flotation is located somewhere below the waterline. This necessarily implies a medium to high draft, which has significant drawbacks (see: Design requirements/incrementalism/draft). Roll-stability can derive from any source; through the use of very deepb allast (FLIP, Spar), or wide footprint (semi-sub), or a combination of both (clubstead) | ||
| + | * Drawback: How big of an air-gap do you design for? Being relatively unaffected by waves up to 10m is great; but how will you handle the 5m of a 15m wave that will hit your platform? | ||
Revision as of 23:07, 13 October 2009
Seastead design features
Many designs for ocean going structures exists, and many have been suggested for the explicit purpose of seasteading. There is significant overlap between these different designs: often, these differences can be viewed as mere variations along a continuous spectrum of some parameter. This section is an attempt at identifying the main features or characteristics a design might have. In this way, we can look at seastead concepts in a more systematic way, avoid reinventing the wheel, and quickly get a qualitative feel for the properties of a given design. Not all designs can be perfectly categorized in such a way, but it creates some order in the chaos nonetheless.
Minimize waterplane area
- Examples: spar platforms, semisubmersibles, clubstead, FLIP
- Rationale: minimize interactions with the waves.
- Implications: Floating vessel derive their stable position on the water from the fact that moving them up and down changes the volume of displaced water. If there is little waterplane area, this coupling is weak. This means the waves will have relatively little effect. On the other hand, the total flotation has to come from somewhere; as can be seen from any of the examples, this implies that the flotation is located somewhere below the waterline. This necessarily implies a medium to high draft, which has significant drawbacks (see: Design requirements/incrementalism/draft). Roll-stability can derive from any source; through the use of very deepb allast (FLIP, Spar), or wide footprint (semi-sub), or a combination of both (clubstead)
- Drawback: How big of an air-gap do you design for? Being relatively unaffected by waves up to 10m is great; but how will you handle the 5m of a 15m wave that will hit your platform?
