Breakwater Design


#283

@ellmer - (#2) - if the Ramform is smaller than the wavelength, then the Ramform’s gravity merely displaces water at the point in the wave crest where the boat’s weight exceeds the wave energy at that point in the crest.

And the Ramform would oscillate (bow-to-stern) around the lateral axis running through the Ramform’s center of gravity as the wave crest moves under the Ramform.

Consequently, the Ramform’s bow (and stern) would rise over the wave’s crest and fall into the wave’s trough … bobbing up and down with each wave.

Only by simultaneously cresting two waves (at a minimum, assuming equal distribution of the Ramform’s weight fore to aft) would that oscillation start to become negated.

And the Ramform’s bow cannot refract wave energy unless it is below the waterline.

So a Ramform’s length (bow to stern) would need to be (at a minimum) several multiples of the most probable wavelengths, or it would not be effective at refracting surface wave energy.

Correct?


#284

(#4) - was answered mostly by the response about tethering.

In contrast to a breakwater - which both retracts/absorbs wave energy and water mass - the Ramform design only refracts surface wave energy away from the Floating City. Displacement by the Ramform doesn’t effect the Floating City.

But, in that refraction, the Ramform’s bow would absorb some energy … causing the Ramform to be pushed to some degree (depending on the angle of the bow, relative to the direction of the wave energy) away from the oncoming wave energy.

Lacking any of the (bow refracted) wave energy, the Floating City would not be similarly “pushed”.

Some mechanism would, therefore, be necessary to keep the Ramform and the Floating City in relative proximity to each other.

Tethering the Ramform and physically connecting the Floating City to the Ramform would address that problem of energy differences.

Thanks for info.


(Robert Campbell) #285

What about seaweed? The sargasso sea acts as a breakwater. So mass - when light individual objects distributed over a broad area - can act to dampen waves.

This is good out of the box thinking, but I’d take it a step further than you did.

Why not design a floating city around the very idea of seaweed aquaculture and plastics recycling, and site it in the middle of an oceanic gyre? You could build a floating kelp raft network a mile across, and put your habitable area in the middle of it. The kelp would effectively act as a mile wide series drogue.

That also gives you another element nobody’s talking about, at least in this thread anyway … sustainable economics. You have an export crop baked into the concept.

edit:

I see I should have read further down.

Crapping on the seaweed farm idea is just as dumb as crapping on the idea of a corn farm because you don’t like corn. You grow corn and sell it and buy whatever you need. That’s how economies work. Without a resource to sell, your entire floating city is just going to be a tourist destination, nothing more.

Instead of looking for a place shallow enough to grow kelp, just sink some long concrete beams off of some floats and grow the kelp on that. Build that into a subsurface hex grid network on pivots, with floats at each of the vertexes of the hex grid, and cultivate kelp on each of the beams. The whole thing undulates in the water, deadens any wave or swell action, and you tie your central living space into the grid. If you site it in the middle of a gyre, it pretty much stays put in the same region we’re collecting plastics trash now, without the need for an anchor - or at least a severe one - because there’s nothing nearby to bump into. If it gets moved by a storm, move it back when the storm is done with some light anchor lines that you pay out during the storm, or with propulsion.

Even if you don’t use all the kelp for aquaculture, it still gives you the breakwater.

And you can use algae as shrimp feed. (as well as some of your sanitary waste) Everybody likes shrimp.

Throw in a plastics recycling operation in the central habitated area to create hydrocarbon fuels for use by the city, while also cleaning the ocean.

That’s the idea. It has a lot of the problems tied up in one neat little bow.

You could fuel the whole city off of methane and sell ethanol to passing boats.

http://www.biomassmagazine.com/articles/2166/british-report-use-kelp-to-produce-energy/


#286

The hull of the Ramform is slanted upward, aft of midship, to the waterline, at the stern, to create the smooth flow, aft of the vessel. As someone that is not a marine architect. I have been in contact with many people, in my study of the Ramform vessels, especially with various departments at PGS, and Mauro Scully, a Marine Architect on the Wally Hermes Yacht prospective designs. I know about as much about the Ramform as anyone that isn’t in direct contact with Roar Ramde, and a Marine Architect can learn, w/o building one, and I’m planning to build testing models for nearby wave-tanks, then my own hull, as well.


#287

I salute your efforts, @JL_Frusha, and agreed that scale models are a helpful (if not mandatory) step in proving the concept.

I’m with you in spirit. :grinning:

My thoughts are relevant to the physics of the problem (of protecting a Floating City), as opposed to critiquing the design of the Ramform (which doesn’t appear to be designed primarily for Floating Cities).

Here’s how I see that in practical terms.

Wave energy is wave energy, regardless of the shape of a hull. Prior to impacting an object (of any shape), a surface wave is simply that … a surface wave. The appropriate physics apply.

While a boat moving through water certainly impacts whatever wave energy exists, the design of a bow is to displace water to the side of the hull.

The various designs of bows achieve various performance results, but the objective is always related to water displacement.That’s what bows do … displace water along the longitudinal axis of the hull.

But Floating Cities are not concerned with any displacement except their own floating structures.

Floating Cities are concerned about surface waves (the energy … not the mass), because surface wave energy creates swells relative in size to the waveform. We see that in the amplitude … 1/2 the distance of the crest-to-trough measurement.

Measured from the [calculation of what would be a] flat surface, the amplitude is the height of the swell. The wave (energy) also extends equally below that flat surface … which is the trough. Beyond that depth, the Floating City need not concern itself with the energy of surface waves.

The function of a Floating City’s Ramform is not to displace water, but to refract the energy of the surface waves away from the Floating City … resulting in the minimization of swells in the area upon which the Floating City floats.

The surface waves (energy, not mass) don’t flow back around the edge of the Ramform to “fill the hole”, as happens with displacement. The energy refracted from the hull (the edges) of the Ramform heads off in a new direction and never affects the Floating City again. That energy goes somewhere, but not to the Floating City.

(This is why the leeward sides of islands have smoother surfaces than do the windward sides. It is also how Polynesian sailors traditionally navigate.)

Thus … no surface wave energy, no swells.

If the Ramform is not as deep as the amplitude, then some of the wave energy will pass under the lower edge of the Ramform’s hull and resurface behind it, visible as a series of swells moving on toward the Floating City … depending on the wave parameters and the length of whatever section of the Ramform under which the wave’s energy is passing.

So … unless your Ramform extends down to (at least) the amplitude of your largest potential physical waves (swells of water rising above the water surface) …

… your Ramform (of the V-shaped design in the photos on this thread) will not keep your Floating City from being tossed, to some degree, by the storm swells. The hortizontal depth (bow to stern) of your Ramform’s “wings”, incidental to the direction of the surface wave, are far too narrow for that.

An artificial kelp or mangrove forest could deal with that residual wave energy, but that’s a slightly different subject.

The weight of the Ramform is what keeps it partially submerged, which consequently allows the submerged portions to refract surface wave energy.

The shape of the bow allows water in the swells to be more effectively displaced sideways, and gravity is the force that determines how much of the swell will be displaced by the bow and hull (i.e., how low the Ramform’s bow will ride in the water and cut through the swell).


#288

I agree with your “biomass absorbs/scatters surface wave energy” idea, @Robert_Campbell.

In fact, I don’t see the financial feasibility of using Ramforms without also using hortizontal vegetation to absorb/scatter the wave energy.

I would add into that … potential use of other plants (e.g., mangroves and/or artificial land for fresh-water plants) as both an energy buffer and as a tourism option (sea camping, diving, fishing, etc., etc.).


(Larry G) #289

Not sure who this was pointed at, but as one person injecting some sanity into the idea, seaweed farming is a good idea. It comes with practical constraints. The middle of the ocean is not a great place to site a commodity production operation. Distance from markets and infrastructure generally makes commodity production marginal at best, impossible if it cannot be done on massive scale. Seaweed farming for local consumption has the benefit of shorter logistical loops, but it’s still not a solution in itself. Any business that has additional cost of infrastructure, logistical transportation, etc typically is better off in providing some sort of value-added product or service, not commodity.

The concept of building a massively expensive structure for a commodity crop doesn’t make much sense, and will never get off the ground. The cost of building “long concrete beams off of some floats” on a “subsurface hex grid network on pivots, with floats at each of the vertexes of the hex grid” sounds considerable. Doing enough of that to grow a substantial amount of kelp (enough to return on investment) sounds like a fantasy. You might be able to find a way to create kelp beds suspended over the deeps, but it would have to be economical and unlikely to be massive concrete beams. you also have the problem of nutrients. Even more so than soil, not all regions of the ocean are equally fertile. For example, the majority of major fishing grounds are in cooler latitudes. This is because warmer waters contain less dissolved gases (O2 and CO2), and because food particles tend to rot faster in warm water than cold. The colder regions of the ocean are murky with plankton and microscopic life that forms the basis of the oceanic food chain. The tropics are deserts by comparison (although colorful deserts, with great ability to clearly see what life exists there.)

The Pacific gyre is hundreds of miles in diameter, thousands of mile in circumference. An item “caught” in the gyre may take literally years to rotate around it, or it may wash up on a beach in a few weeks. Tsunami debris started showing up on our Washington beaches less than a month after Fukushima. It’s not “staying put” in anything like a human scale “region”. And things do spin out of the gyre regularly onto the shores of island and continents. You have to look at the scale. It’s not a circular current in a large lake. It’s a weather and current pattern that spreads across most of a hemisphere of the earth.

Every so often, someone brings this up again. It is not feasible. The density of microscopic plastic in the gyres averages in the parts per million range. There is no "island of floating trash the size of Texas." It’s a fraud, echoed over and over again by well-meaning but ignorant people, and unethical alarmists shilling for funding. There is more visible, macro-scale trash along a few routes that are heavily traveled by cruise ships, freighters, and popular yachting destination, but the majority of the area would never yield a detectable concentration of plastic to the naked eye.This is well-established in scientific literature, you should disregard the popular media on this topic.

What might well be feasible, is a mobile processing facility to produce fuels by pyrolisis from plastic trash that exists in Island and Coastal nations, or a mobile bio-fuels processing plant that goes where the feedstock is.


Mobil Bio-fuels processing
(Larry G) #290

Absolutely: on a massive, widely distributed (space AND time) scale. If you want a point-source change to wave energy, you start seeing a lot more difficulty and expense involved.


#291

The Ramform Titan series IS capable of being a small floating city, HAS been proven in storms in the North Sea.

My specific application will be for my wife and I. Not interested in hosting a city, or even praise, or other opinions. Done my reseaech, have multiple concepts, some will work better down-current from something like the real Ramform.

The upward slope of the aft section of the hull is shaped in order to create a ooth flow, with reduced turbulence, unlike the wake of other vessels. This smooth flow makes for reduced noise, to increase sensitivity of the microphones, resulting in more accurate scans.

This silence was recognized and further developed by Roar Ramde, based off the Marjata, a special vessel made for the Norwegian Navy, which detected and recorded the Kirsk Disaster, from too great a distance to assist.

My wife and I are determined to do what we can, to get offshore, living independently of most land services. I expect the Ramform to take several years to build, and will be building a variation of the Little SSLV (semi submersible lfting vessel), innitially, while the larger hull is being built and fitted out. Then the Ramform will be deployed upstream, for better conditions around the semi-sub.

Currently working on other, supporting projects, while searching for an appropriate property to build on, near the GoMex (Gulf of Mexico), to facilitate float-out and the potential of others to come build their own.


#292

While the topic it Breakwater design, it appears to be migrating to a dual discussion on Ramform vessels.

The Ramform, as developed, patented and copyrighted named by Roar Ramde, and exemplified by the Ramform Titan series, and the fantasy Ramform City as dreamed up by @matias and @ellmer

The two are not synonomous and should not be confused.


(Matias Volco) #293

Ramform is a growing, evolving, and mutating creature - and nothing more complicated than a shell structure with side almost tubular wings that grow over time. This structure is a large bulding, part of the city itself. It can be connected to boats and houseboats within its moonpool.

If a stationary location is desired it can be moored with a Turret Anchor, although that is not the only option (see pics in thread)

If a ramform grows well beyond the size of a working breakwater it transforms into another creature, perhaps a bubble cluster, where the bow ceases to be of importance.


#294

Okay … I’ll switch to Surface Wave Oscillation Refraction Device (SWORD) …

… so that no one will confuse the defective design of the Ramform with a device intended to refract the energy of surface waves.

The SWORD deals exclusively with the refraction of surface wave energy …

… as opposed to breakwaters, which are designed to deal primarily with mass.

Further, the SWORD incorporates a bow into the design …

… solely because that maximizes the equalized displacement of swell mass along the longitudinal axis of the SWORD, which is the most effective means of pointing the SWORD directly into the reciprocal direction of the surface waves.

Does that remove the confusion over terms, @JL_Frusha?


#295

FYI, @Matias

… I’ve change from using Ramform to using Surface Wave Oscillation Refraction Device (SWORD)

… to avoid confusion with the structure @JL_Frusha is planning to build near GoMex.


#296

I was clarifying “Ramform” vs ‘Ramform City’.


#297

Thank you for welcoming me to the forum, @JL_Frusha.

Never a dull moment among the SeaStead crew, eh? :wink:


#298

Quite a charming way of introducing yourself.

I do tend to fire back, but I did not set loose the first volley.

Since initial insults have been exchanged, welcome to the pool. Jump in. Water ranges from Polar to sub-sea-thermal-vent. Plenty of room and variation for all.

This is the Ramform Titan:

Gross Tonnage: 20637
Deadweight: 7351 t
Length Overall x Breadth Extreme: 104.2m × 70.02m
Year Built: 2013
Status: Active

Read more at http://www.marinetraffic.com/en/ais/details/ships/shipid:372038/mmsi:311000084/imo:9629885/vessel:RAMFORM_TITAN#Wrwb28VBCRhF2XCr.99

Largest Ramform, so far, with a larger version supposedly under construction.

The configuration and its extent affords PGS considerable survey flexibility, faster deployment and recovery of the recording gear, and enhanced overall efficiency, with the requisite operational safety. She will typically tow more than 12km² of equipment, encompassing several hundred thousand advanced recording sensors encased in 16 or more cables, each up to 10km in length, suspended 10m-20m below the surface. By installing a 24-reel outfit, the owner has ensured a very high level of operational redundancy as well as increased potential for the future.

The lateral offset of the streamers is achieved by deflectors. Ramform Titan applies the successful deflector handling arrangement used on the preceding S-class.

The sinusoidal waterline makes for stable motion behaviour across the beam, with the proportionally vast back deck ideally suited to the installation, deployment, retrieval and towing of the extensive seismic gear and related equipment, and affording substantial, interior instrument room capacity.

http://www.motorship.com/news101/ships-and-shipyards/latest-ramform-pushes-the-bounds-in-seismic-vessel-technology


#299

This comment thread is about “breakwater design”.

Your affection for the Ramform Titan boat is noted. I hope it works well for your project in GoMex, @JL_Frusha.


(Matias Volco) #300

The sinusoidal waterlline, like the bulbous bow, are streamlined for speed and particular specs . The 100L by 70B proportio is what matters about Seismic ships. Other examples of the ramform principle include wide regatta sailboats, the protected aft area where a dhingy’s propeller is most efficient, havfarm, and Prelude.

the ramform principle relates to breakwater because it allows a gradual bridge between a single relativ. modest project and the imagined large macroeconomic round breakwater.


#301

There ARE no other examples, that meet the patents. PGS has ALL of the Ramform vessels. Some happen to be stored for future use, they might be available, if the price was right.

CLOSEST thing is art from various yacht designs, which also conform to the patent descriptions.


#302

… and back to breakwater…

Using a Ramform hull to smooth the water, downstream. for smooth water-flow for streamers to grow kelp, is an ideal moored concept, for a smaller, family scale seastead/Gulfstead, to raise food foe pens of fish, Abalone, etc.