New propulsion sytems for ships

[charmc]

Because of previous criticisms of the Flettner rotors causing heeling similar to that produced by conventional sails, it will be interesting to follow the progress of the new Enercon ship. The placement of the rotors seems designed to minimize reduction of cargo space.

[Guillermo]

According the Alcyone’s skipper Bernard Deguy, who sailed hundred of miles on the ship all around the world, Turbosails (Flettner rotors) results were quite poor. “ First we never use the fans atop the masts. Because the noise, it is impossible for the crew to sleep inside the boat. Secondly, we need a good breeze coming from amidships to notice that the Turbosails are producing power. In fact, we are motoring most of the time !”.

See Post # 18 in this thread.
Cheers.

[Kiteship]

Originally Posted by Guillermo

According the Alcyone’s skipper Bernard Deguy, who sailed hundred of miles on the ship all around the world, Turbosails (Flettner rotors) results were quite poor. “ First we never use the fans atop the masts. Because the noise, it is impossible for the crew to sleep inside the boat. Secondly, we need a good breeze coming from amidships to notice that the Turbosails are producing power. In fact, we are motoring most of the time !”.

With respect, Guuillermo, the Turbosail on Alcyone were in no way a flettner rotor. Alcyone's "sail" did not rotate at all. The claim that it was rarely used "because it annoyed the crew" I find fantastic--to the point of disbelief.

The turbosail *requires* the fan to be turning to work at all. Without the circulation it is simply a big round pole in the middle of the deck. By all contemporary reports, the Turbosail worked very well--better than it's specs. Did you mean to say that your acquaintance sailed her "hundreds of miles"? That'd be only a total of only a few days aboard. Such short knowledge of the system could well be incomplete.

The Alcyone itself was a horrible boat--again by contemporary reports--its hull shape had the very quick rotational motion of a multihull, but without the accompanying stability--in short she rolled, and rolled, and rolled...

What killed the true flettner concept wasn't heeling moment--the rotors can be shorter than equivalent masted sails--but rather vibration problems associated with the rotation itself--the rotors need to turn at a good clip--and more importantly the gyroscopic effect as the boat pitches and rolls. Not large enough to actually damp these ship motions, the rotors' bearings suffer huge (truly huge) forces and fail. I too will be interested to see how the Enercon ship fares. (I bet they go to Turbosails, myself!)

Dave

[Kiteship]

Originally Posted by FAST FRED

The piston engines I flew had water injection. (For take off ONLY)

Any Alcohol was ONLY there to keep the water tank from freezing at altitude and bursting the tank.

Water injection WORKS ( if you remember to fill the tank) at reducing detonation at very high power settings,

Not very likely of use an any but Drag boats.In cars it could be fine , esp with todays computers.
Drag racers (auto) in the 50's simply used a vacum operated system that allowed the water to be injested when the throttle was open far enough .

FF.

There are very real proposals to add water emulsion to ship diesel fuels. Not part-time, but for continual use. Check out MAN and Wartsila sites for more on this.

Dave

[Guillermo]

Originally Posted by Kiteship

With respect, Guuillermo, the Turbosail on Alcyone were in no way a flettner rotor. Alcyone's "sail" did not rotate at all.

Yes Dave, you're right, of course.
There's some time since I don't find you around in these forums. Everything's going OK?

[Kiteship]

Originally Posted by Guillermo

Yes Dave, you're right, of course.
There's some time since I don't find you around in these forums. Everything's going OK?

Everything's going great, thanks, Guillermo. We're heads-down trying to get our next prototype (very big) financed and out into the wind.

Dave

[mydauphin]

Originally Posted by Kiteship

There are very real proposals to add water emulsion to ship diesel fuels. Not part-time, but for continual use. Check out MAN and Wartsila sites for more on this.

Dave

Please don't add water to any diesel or gas fuel. I reduces heat energy of fuel and doesn't accomplish anything except wear on engine.

The only reason to add water injection into a engine is to cool air intake but humidity lowers hp also. People like myself used water injection in the old high compression (10:1) v-8's because we could not get the higher octane gas. But it ran better with avgas which had over 100+ octane.

The purpose of the water emulsion is not to increase fuel economy but reduction in NO levels

I will tell you what does work. Get a 200hp diesel add propane injection... get 300 hp and better gas mileage, more efficient combustion. But are using propane at the higher power level.

You don't get anything for free. Calories in - Calories out
If you want to add water to your fuel, mix in some sugar... At least that way it has some more calories to generate heat.

[Kiteship]

Originally Posted by mydauphin

Please don't add water to any diesel or gas fuel. I reduces heat energy of fuel and doesn't accomplish anything except wear on engine.

The only reason to add water injection into a engine is to cool air intake but humidity lowers hp also. People like myself used water injection in the old high compression (10:1) v-8's because we could not get the higher octane gas. But it ran better with avgas which had over 100+ octane.

The purpose of the water emulsion is not to increase fuel economy but reduction in NO levels

I will tell you what does work. Get a 200hp diesel add propane injection... get 300 hp and better gas mileage, more efficient combustion. But are using propane at the higher power level.

You don't get anything for free. Calories in - Calories out
If you want to add water to your fuel, mix in some sugar... At least that way it has some more calories to generate heat.

I don't believe I suggested that adding water would increase the energy content of fuel--I certainly did not mean this. There are a number of problems with big marine diesels and pollution--for instance they create a criminal amount of NOx, due to the very lean burn at very high combustion temperatures they use for "efficiency." Certainly water injection would affect this, and certainly there would be side effects. I don't pretend to understand the complex engineering tradeoffs facing giant diesel engine production, operation and maintenance; I only report the news as I learn it. ;-)

Cheers,
Dave

[marshmat]

That's something a catalytic converter can and does solve in cars, though. While the high temperature the catcon needs is a significant problem in a small, enclosed engine room, the rationale for not fitting larger marine diesels with a converter and/or DPF (diesel particulate filter) as new transport trucks have, is sketchy at best. These are technologies that are fairly well understood and are known to have a big effect on cleaning up the exhaust, at an increase in capital cost that's really not very big when you look at the complete engine installation.

[mydauphin]

[quote=marshmat;152654]That's something a catalytic converter can and does solve in cars, though. While the high temperature the catcon needs is a significant problem in a small, enclosed engine room, the rationale for not fitting larger marine diesels with a converter

Their fuel is like tar, requires pre-warning to be fully liquid. But it is dirt cheap. So my guess they want to mix tar and emulsifier to make it easier to pump and cleaner to burn.

[marshmat]

At least there's something around that can use that crud, rather than just dumping it in a hole in the ground....
Perhaps part of the problem is that these big ships are all flagged in countries with little to no environmental regulations, thus little to no incentive to spend the money to clean them up. If there were a way to mandate the use of catcons and/or DPFs on ship diesels (it's technically feasible, if anyone were interested in buying such exhaust-cleaning gear) we'd see NOx, particulate, etc. emissions from ships drop substantially. It's working for transport trucks- an '07 unit doesn't put out any black smoke at any speed, very much unlike the older diesels. But who's going to set and enforce such requirements for ships? Right now, nobody.

[Kiteship]

Originally Posted by marshmat

At least there's something around that can use that crud, rather than just dumping it in a hole in the ground....
Perhaps part of the problem is that these big ships are all flagged in countries with little to no environmental regulations, thus little to no incentive to spend the money to clean them up. If there were a way to mandate the use of catcons and/or DPFs on ship diesels (it's technically feasible, if anyone were interested in buying such exhaust-cleaning gear) we'd see NOx, particulate, etc. emissions from ships drop substantially. It's working for transport trucks- an '07 unit doesn't put out any black smoke at any speed, very much unlike the older diesels. But who's going to set and enforce such requirements for ships? Right now, nobody.

Regulators have finally determined a way to enact regulation. The ship may be flagged anywhere it pleases, but it may not enter a given port or unload unless it can prove it is in compliance with national and international regulations. Europe already has extensive SECA zones--out to 200 miles, well beyond national borders--where ships must burn low sulfur fuel, and prove they have done so, before they may land.

Of course not all ports require compliance--yet--but most ships comply. Regulations will and are becoming more stringent and there is much ballyhooing about what is possible and how soon, but the ship owners are complying. There is a move afoot from inside the industry, for instance, for all ships to change from residual fuel oil to distillate fuel, a much cleaner--though much more expensive--alternative.

It is an interesting time for a business such as ours (we build kites for converting ships to hybrid sailcraft). We have designed the product and business model to stand on its own--the device must save more than it costs or will not meet acceptance. It is interesting to find that finally, sails' ability to reduce pollution levels has been given a more or less cash value, adding to the demand for them.

Dave

[Guillermo]

Big ships use to burn IFO 380 (RME 35) or IFO 180 (RME 25) fuels, with sulphur content up to 5%, which is pretty high.

Marine fuel currently contains on average 2.7%, or 27,000 parts per million (ppm), of sulphur, compared with petrol for cars, which will have 10 ppm sulphur content from 2007. As part of its ship emissions strategy, the EU adopted in 2005 the following provisions:
- a 1.5% sulphur limit for fuels used by all ships in the Baltic Sea, from 19 May 2006, and the North Sea & Channel, from autumn 2007;
- the same 1.5% sulphur limit for fuels used by passenger vessels on regular services between EU ports, from 19 May 2006;
- a 0.1 % sulphur limit on fuel used by inland vessels and by seagoing ships at berth in EU ports, from 1 January 2010.

Still some way to go....

See:
http://eur-lex.europa.eu/LexUriServ/...en00590069.pdf
http://en.wikipedia.org/wiki/Fuel_oil
http://www.marineexhaustsolutions.co..._det.asp?id=54

[Kiteship]

Originally Posted by Guillermo

- a 0.1 % sulphur limit on fuel used by inland vessels and by seagoing ships at berth in EU ports, from 1 January 2010.

Still some way to go....

So true. Still, it is encouraging to note that, at least here in California (and, I suspect elsewhere), when 0.1% sulfur fuel is stipulated (1000 ppm), ship operators generally comply by burning highway diesel, at 15 ppm sulfur. There's a minor difference in required flashpoint between road diesel and MGO, but that's evidently easy for the refineries to alter and supply. If Intertanko (and others) get their way, all big ships may--voluntarily--change over to distillate fuel, at under 0.1% sulfer.

Nowhere yet, to my knowledge, are NOx limits set or enforced as yet. Big diesels create much more NOx than either smaller diesels or automobiles--even without pollution control gear in place. Still, this will change, too. FWIW, Diesel creates about 20-25% more CO2 than gasoline as well (more carbon in the molecule)...

Dave

[Guillermo]

MARPOL Annex VI has now been ratified by 41 countries,as far as I know, but not yet by 7 EU Member States: Austria, Czech Republic, Hungary, Ireland, Malta, Portugal and Slovakia, even though it was adopted in 1997 and entered into force on 19 May 2005 (And 2005 ammendments on 21 Nov 2006). The fact that 7 EU members still have not ratified the Annex continues to undermine the commitment of the EU to low-emission shipping, and also weakens the negotiating of amendments to tighten the provisions of the Annex.

NOx emission limits are set for diesel engines over 130 kW, which range from 9.8 to 17 g/kWh depending on the engine maximum operating speed, as shown:
n < 130 rpm: 17.0 g/kWh
130 rpm ≤ n < 2000 rpm: 45 x n^-0.2 g/kWh
n ≥ 2000 rpm: 9.8 g/kWh

On the problems of controlling NOx emmissions from ships, read the clarifying:
http://www.dnv.com/publications/clas...inedmarpol.asp