Brain Teaser: Renewable Powered ‘Flying’ Yacht

[portacruise]

Some more out of the box stuff , haha!

Maybe the decoupling can be done with a combination of hydrogen balloon and adjustable pitch hydrofoil? The balloon pulls up and the hydrofoil pulls down or pushes up as needed to keep the craft suspended above wave motion during propulsion? Or giant 3D shock absorbers for a suspended living quarters only, something based like the best automobile suspension systems, or actively controlled by electronic systems based similar to the concept of noise cancelling technology?

Ps. Flight simulator room run backwards to decouple, to smooth bumps? The danger being that if a rogue wave is coming, you might not have any forewarning.

 

[zstine]

My guess is that using the oxygen won't help efficiency that much, and might introduce more things that can go wrong.

Most of the energy in a gallon of gasoline (or hydrogen) is released in the form of wasted heat, with an ICE, from what I understand. I think it's mostly the explosion part that drives ICE forward, and that may only amount to 30% or less of the total energy, according to some sources. I don't see how pure oxygen would help that, unless the explosions somehow become more violent for the same chemical reaction? Heat and nitrogen oxides produced by a hydrogen ICE are not helpful to the environment, if that be a consideration. On the other hand, electric power plants are more efficient compared to ICE, probably because they use the heat part and not so much the explosion part, as well as scale. Fuel cells can be closer to one hundred percent efficient because they are not heat engines, and they produce much less, (if any),of Heat, nitrogen oxides, or carbon when run on hydrogen fuel. Of course everything has Cradle and Grave consequences which need to be considered, haha! Thanks for the interesting links above!

Yup, I agree efficiency won't be changed much by running pure HHO. But the output for a given displacement would go up significantly b/c you don't have all that nitrogen filling up the cylinder. Air is 78% N, so I'd think you'd double output for a displacement running pure HHO. And yes, it eliminates NOx emissions completely, which is a big deal. Yes, Fuel Cells are MUCH more efficient, and that would allow for a smaller solar array, smaller HHO Generator, smaller storage, all cheaper. BUT they are STUPID EXPENSIVE! I found a 6kW PEM fuel cell for $27,000 ( fuelcellstore.com) and I'd need 2 of them to keep up with average cruise power. $54k blows away all the savings on the other equipment and then some. Plus you need Lithium batteries $ to obtain bursts of full throttle ~30kW, and motors $, motor controllers $, etc. The ICE engine would be under $10k and needs nothing else, just a shaft and prop.

 

[zstine]

Some more out of the box stuff , haha!

Maybe the decoupling can be done with a combination of hydrogen balloon and adjustable pitch hydrofoil? The balloon pulls up and the hydrofoil pulls down or pushes up as needed to keep the craft suspended above wave motion during propulsion? Or giant 3D shock absorbers for a suspended living quarters only, something based like the best automobile suspension systems, or actively controlled by electronic systems based similar to the concept of noise cancelling technology?

Ps. Flight simulator room run backwards to decouple, to smooth bumps? The danger being that if a rogue wave is coming, you might not have any forewarning.

Yeah, no way the H balloon is going to lift anywhere near the 15,000lbs + the boat would weigh. I was thinking just a few thousand pounds of lift. You would have to supplement the lift from the H balloon with another lift mechanism., be it a buoyancy bulb, hydrofoil, gyro plane, Flettner rotor. The issue with hydrofoils is the operating speed. At take off speeds below 8knts, the foild have to be enormous to create enough lift. So you need something that will produce lift at lower speeds. The Flettner rotors are interesting.

Check out Quantum stabilizers. A 1.5 meter, 0.2 meter diameter rotor produces 50kN (11,240lbs) at 10knt! That's a lot smaller than a hydrofoil would be for that lift and speed. The problem is the power to spin the rotor is significant.
Quantum MAGLift Rotor Stabilizer - Magnus Effect - Quantum Marine https://quantumstabilizers.com/products/maglift-magnus-effect-rotor-ship-stabilizers/

A fully suspended Habitability space is an option to decouple. There are a lot of smaller vessels running suspension. I'm wondering how to figure out the 'real' pros and cons of the various decoupling options (Suspension, small waterplane, foil/rotor lifting, hybrids, Gyro stabilizers, other??) without having to do a detailed design study of each which would take many months or even years. When you read about them, there's often sales pitch BS included.

 

[tlouth7]

Hi tlouth7,
I wouldn't just discount water ballast. The tankage could/would be located in the demihull/keel and not in habitable space. One issue with small waterplane is scaling it down to a sub-50ft size and maintaining good stability. How would you do that? Also, the mature propulsion for renewable power would of course be sail. But the small waterplane does not play well with the over-turning moment of sails. So, If you think small water plane is the best choice, what do you think is the best way to power it?

Water ballast in the keel would make for an extremely fat, high drag keel. Water ballast in the hull makes sense, but it increases volume that is not useful for stowage/living.

I would maintain good stability and sufficient righting moment for sailing, despite a small waterplane area, by having a deep, heavy keel and by accepting a high angle of heel while sailing. Such a vessel is sometimes called a plank on edge. Alternatively a kite sail would be a potential way to reduce heeling moment from the rig.

 

[zstine]

Water ballast in the keel would make for an extremely fat, high drag keel. Water ballast in the hull makes sense, but it increases volume that is not useful for stowage/living.

I would maintain good stability and sufficient righting moment for sailing, despite a small waterplane area, by having a deep, heavy keel and by accepting a high angle of heel while sailing. Such a vessel is sometimes called a plank on edge. Alternatively a kite sail would be a potential way to reduce heeling moment from the rig.

I guess I'm not following you. First, any heavy keel has to be displaced by water. If you add a ton of keel, you have to add a ton of buoyancy. I don't see that significantly reducing surface area over water ballast. So how does the keel help reduce drag compared to movable water ballast? I looked up 'plank on edge'. I found old school mono's that are long and slender, nothing like a catamaran SWATH. How does that apply to small water plane? Are you suggesting a ballast bulb at the bottom of the keel? And the moveable ballast part is critical since hull stability is generated by the movement of CB as the boat heels. In a SWATH the movement of CB is very very small due to small waterplane. So without a movable ballast, I don't understand how that heavy keel is going to add a significant righting moment at 20deg of heel. I'm confused by how your concept works. Maybe you could draw a quick diagram?
thanks

 

[Will Gilmore]

You could stabilize a disconnected floating superstructure, float the living quarters above it, even use wave heave to generate power. The main hull could even be below the waves, when at sea.

I can get further out of the box, but I think we are at the limit of any semblance of practicality.

-Will, the autistic thinker

 

[portacruise]

Zstine, maybe using pure oxygen in a hydrogen-powered ICE would be similar to turbocharging, which increases power, but without the need for a mechanical turbine? If that's the case, definitely get a lot more power with pure oxygen, haha! I like the nauti-craft solution for decoupling though I pictured it being done with a single hull, cannot tell if it is mechanical or hydraulic in nature? Mechanical might be simpler and more energy efficient since it doesn't require hydraulic pumps, fluids, Etc.

On the cost of fuel cells, seems it might be cheaper to buy a mass-produced fuel cell powered car or bus once they become mass-produced, or a replacement fuel cell for that car, then adapt it to your boat? It appears that Energy Observer did something like that.

 

[zstine]

. . . I like the nauti-craft solution for decoupling though I pictured it being done with a single hull,. . . On the cost of fuel cells, seems it might be cheaper to buy a mass-produced fuel cell powered car or bus once they become mass-produced, or a replacement fuel cell for that car, then adapt it to your boat? It appears that Energy Observer did something like that.

Balance on 1 hull! Yes, of course, duh! It eliminates roll via form factor, not the suspension. So, heave really becomes the only motion you need to deal with on the suspension side. Yaw and surge are not really the types of motion that are at issue here. I'm imagining a catamaran house boat with a third middle hull, like a trimaran, but the middle hull can extend downward on active suspension lifting the house boat clear of the water when at speed. You run on the long slender body of the main hull and it is balanced (computer control) like a bike to keep the CG over the CB. That actually seems pretty easy.. no more complex than my kid's 'hoverboard' right!? Well, until you start to add wind or kite/sail power. Then the whole thing has to lean or heel against any side loads. But still doesn't seem hard by today's standards with 'one wheels' zipping around.
Good idea on the used hydrogen/fuel cell car source. Not easy to find now, but maybe in 5 yrs it will be.

 

[tlouth7]

I looked up 'plank on edge'. I found old school mono's that are long and slender, nothing like a catamaran SWATH. How does that apply to small water plane?

I'm not talking about a catamaran SWATH, I am talking about a monohull with a small waterplane area. Stability comes from the righting moment of a deep ballast keel, combined with high sailing heel angles.

Water ballast in this context serves the purpose of increasing total mass in heavy weather, and so reducing motion. It does not need to be noticeably low down, so putting it in a very large, draggy keel would be counterproductive. Yes the boat will have high wetted surface area when fully ballasted, but that is the inevitable price of low waterplane area (for a given displacement) however you achieve it.

 

[zstine]

I'm not talking about a catamaran SWATH, I am talking about a monohull with a small waterplane area. Stability comes from the righting moment of a deep ballast keel, combined with high sailing heel angles.

Water ballast in this context serves the purpose of increasing total mass in heavy weather, and so reducing motion. It does not need to be noticeably low down, so putting it in a very large, draggy keel would be counterproductive. Yes the boat will have high wetted surface area when fully ballasted, but that is the inevitable price of low waterplane area (for a given displacement) however you achieve it.

Hi tlouth7, I'm trying to understand your concept 'righting moment from deep ballast'. Below left is what I'm picturing with the ballast low and a very low CG, but clearly this design is unstable at rest and could only be stable under way if it had some computer controlled foils or something to keep the CB under the CG as the CB will not move when heeled as it would with a waterborne hull (below right). So, I'm guessing you are thinking something very different than the below drawing. Let me know.

 

[tlouth7]

Yeah no I wasn't thinking of something like that. More like this:

 

[gonzo]

That looks a lot like the sections of an old Channel cutter. They sailed on their ear, which is OK if you don't mind the extreme heeling.

 

[zstine]

Yeah no I wasn't thinking of something like that. More like this:
View attachment 177701

I see how that would be stable, but it's not a small waterplane. So it wouldn't be decoupled from the seas and would bob around in the waves.

 

[tlouth7]

That looks a lot like the sections of an old Channel cutter. They sailed on their ear, which is OK if you don't mind the extreme heeling.

Yes that is the idea - in fact there are some even more extreme examples of historic plank on edge yachts. Severe heel underway does not appear to violate OP's brief!

I see how that would be stable, but it's not a small waterplane. So it wouldn't be decoupled from the seas and would bob around in the waves.

It is a small waterplane area compared to a standard yacht, and coupled with high displacement that will give a much reduced motion.

 

[Will Gilmore]

It is a small waterplane area compared to a standard yacht, and coupled with high displacement that will give a much reduced motion.

I would be surprised if that were so. I would think the deep ballast would act as an anchor in the liquid medium underneath the surface waves. The hull would both heave and be shoved back and forth with each passing wave. The result would be roll as the hull pivoted around the more stable keel ball.

If it is too hard to gimbal the working space of the whole vessel. Perhaps individually gimballed elements of that space would be a good compromise.
halbkardanische Koje | kardanische Schiffskoje | gimbal bunk | gimbunk http://www.gimbunk.com/

The concept is simple. And can be refined by adding a second axis.