New propulsion sytems for ships

development of waterjet propulsion

Dear Guillermo,

I'm looking for the first developments of waterjet propulsions. I wands read that the first water jet was based on a cylinder principal. Comparable to a membrane pump. My question is if you know something about this principal and why this development stopped. Was it the inconstant flow or was it something else?
Kind regards,
Daan Coolegem

 

My understanding is that Williams ran into financial trouble. They had a really innovative engine, but I believe they didn't have enough investment to make it fly. Developing a new class of engine takes many years; in a marketplace driven by quarterly reports, it's not easy for a small player to do something big. Then again, if the military were involved, they'd certainly want to hide it. I'd note that almost all such new-engine-technology ventures by small firms have failed for similar reasons- the OX2 class, several innovative rotaries, etc.

Fred, I don't mean to offend you, but the oil shortage you refer to as being a long way off is in fact more like 10-20 years off. I realize that not everyone has access to academic publications and internal corporate data, and so many people rely on the media for such predictions. Looking through the internal reports of the oil companies, though, reveals that despite vast increases in exploration funding, no large new oil fields are being found. Not one comprehensive evaluation of total oil reserves has put the absolute production peak any later than 2027; most estimate around 2015-2020 if not sooner. It should be noted that both independent and oil-company geologists generally agree on this issue. It's not something we can afford to ignore.

 

Sam Williams and perhaps private investors own Williams International, not a public stock company. Eclipse was tied to a Russian perfume guy with a shady past. Paul Alan and the boys had to rework that and lots more after 9/11/2001 to get the Eclipse 500 off the ground.

I think you are right about the cost, Williams did not have the govenment writting the checks on this one and learned a hard lesson dealing with the private sector.

 

Have you checked their stock lately?

Almost doubled in a week.

Wish I had money to invest with.

 

yes, that was what I have read...but again, the wild development in China, that I believe is going to be quickly followed by India, makes these estimates quite inacurate.
Anyway, prices of oil are going to skyrocket a lot sooner than that...and for having fusion energy available, which most people see as the ultimate solution to energy problems, scientists think it is going to take at least 50 years of development.
That leaves a big hole without any viable energy substitute, at least to the huge quantities we spend per capita in the western world.
Big changes in our way of life will be inevitable.

 

VEGA:
I posted about JVE in my firt post. I'm also wondering why there seems to be so little excitement about this engine...

DAN COOLEGEM:
I have no idea, sorry, but you may find something probaly related at:
http://www.cnse.caltech.edu/Research/reports/polsenberg-full.html
http://enstrophy.colorado.edu/~mohseni/PSpdf/MyPapers/UUST2005a.pdf

RAGGI THOR:
Sails may show useful for certain applications, but I'm watching through this thread several other very interesting means of propulsion coming to surface. So, Maybe another frustrated era of commercial sails...?

ALL:
Have a look at:

YAMATO I, magnetohydrodynamic vessel

"Outside the Box" technologies

 

Re- "outside the box"
There's an awful lot of interesting stuff here. Kind of afraid to look into certain things, for fear the US government will be on my tail....
No scientific theory is ever complete or perfect. Newton's laws are not facts; they're very close approximations to actual systems in certain circumstances. The same goes for quantum theory, relativity, string theory, etc- all approximate models of what we observe. Simply because something comes along that is different is no reason to toss it out (how do you think Galileo got himself in trouble?), a hypothesis can only be rejected when it is proven to contradict physical evidence. Any 'scientist' who rejects an idea offhand with no evidence to back up his rejection, is not worthy of his title.

 

The trouble with water jets is that they send out a relatively narrow column of water that has to be accelerated more in order to provide the same amount of thrust as a wide column. So eccelerating a narrower column that has half the mass as the wider column will require nearly twice as much hp as the wider column did.

This is plainly bad economics all around. Especially in an industry that has to get by with a 2 to 5% profit margin. The prop is here to stay. Wind and solar energy are what really needs to be looked at.

I imagine very large ships will be nuclear powered more and more as the cheap oil runs out. The economics of running a very large ship (300m or more) will simply be too good to pass up. Especially for trans continental use. Even if, because of its higher speed, it has to be exclusively engine propelled.

Smaller ships of 100m or less will someday most likely be mostly sail propelled.

Bob

 

yes sir, wind power, super litho-ion batteries, high efficient solar cells and super conductor electric engines will change the shipping industry within a decade!!!!

 

Superconducting motors, yes. Wind, yes.
I wouldn't put too much faith in either batteries or solar photovoltaic over that timeframe though. GaAs solar cells are still over a hundred bucks per 4-inch cell. Five kilowatt-hours of LiPo battery is still twenty thousand bucks, plus protection circuitry, and they're awfully easy to destroy. There will definitely be big improvements to come- such as totally new solar cell technologies currently in the labs- but a lot of the effects are still quite some time away.

 

When I had a look at the site of Solomontechnologies and understood that the best they can do is 4 hours of continuous work from an electric motor, before having to recharge batteries, I have lost interest. That could be interesting for a daysailer or a racer, as an auxiliary motor. Not for a cruiser that sometimes (when bad luck strikes) can use its motor nonstop for 48 hours or more.

What I didn’t understand was why Nigel Calder wanted one on is Malo 45, his new bluewater cruiser.

I have heard some crazy talk of having a generator making electricity for running the electric motor. That doesn't make any sense to me, because with two energy conversions in between, with losses in each one, surely the result would be worst than running directly a conventional diesel.

Well, I don’t understand very well why, but they get a more efficient performance with the generator and the electric motor. This is not the same concept of Solomon technologies; these guys propose to run the electric motor primarily, not on a big bank of batteries, but on the electricity produced by a diesel generator, using an almost traditional bank of batteries.

The company that leads the technology is Fisher Panda and when I have read that they had experimented the motor on a Bavaria 49 (5000 miles) with fuel savings up to 78%, I got very interested.

http://www.bavaria-fischerpanda.de/eng

http://www.aziprop.de/E_0098B269F5A950DAC1256E68003E7E45_6C775508FC8D3C0B00256CC3003DC561.html

http://www.whisperprop.de/E_1FEF76507EF4738DC1256E68003E64FC_30545F2B2B895624C1257035001F8D2C.html

http://www.bavaria-fischerpanda.de/E_7_2_2_l.html

http://www.aziprop.de/E_0098B269F5A950DAC1256E68003E7E45_444107261F4CBBB200256CC3003DC559.html

http://www.solarnavigator.net/fischer_panda_diesel_electric.htm

What do you think of it:?:

 

A note on water jet drives for fast freighters....
http://www.cdicorp.com/government/files/Govt Serv Marine Design Case Study.pdf
CDI is claiming theoretical pump efficiencies of over 90% from driveshaft to thrust. Still 57,000hp of gas turbine is needed to turn the thing, of course, so it's not exactly a low-energy-use system. But it's a trend in freighter design to go for fast ro-ro, for sure.

 

What about gas?
We have some ferries running on natural gas and methane.
Methane can be made from waste when it's rotting
There is a lot of hype around hydrogen now, but most people forget to ask where hydrogen should come from. We can use hydro-power (waterfalls) to make hydrogen, but why? Maybe solar energy can be used to produce hydrogen?
Iceland is soon the first country to use only renewable energy, they are 300.000 persons and have a lot of waterfalls and thermal heat a few feet down in the ground. I suppose their large fishing fleet is not included in the "all renewable" picture?

 

My ship electric

One of the reasons passenger ships use diesel electric is so they can convenietly tranfer energy around. For instance, when the ship is at anchor wouldnt be nice to be able to use the ships main engines to heat shower water and run blow dryers and air conditioning for the passengers? Especially if it saves having to carry a large gen set and all its support systems.

One problem with internal combustion engines is that they seem to have just one speed they like to run efficiently at. Running them too slow or running them too fast over long periods of time can harm them.

If you have a ship that runs at one speed, like most cargo ships do, most of the time, that is hardly a problem. Just pick the right engine and prop for your desired speed and you're set. That's what I plan to do if I ever design a motor sailor. The motoring part will be almost exclusively for flat wind and near flat water conditions. And it will be for speeds significantly below LWL (4kts for a 27ft WL) speeds.

A boat like this in the wrong hands, though, can be a dangerous thing. If the skipper is depending on brute engine power to get him out of trouble, he will be in for a rocky surprise.

The beauty of electic motors (DC) is they have a much wider range of efficient speeds. So if I wanted a motorsailor that could loaf around on flat calm days to get the best milelage, yet have enough brute power to fight off a lee shore, I would go with diesel electric model.

For this reason, I expect to see that system on sail assisted motor ships and motor assisted sailing ships by the fourth decade of this century.

Bob

 

Popular science-fiction

I agree with you absolutely, Marsh. But nowdays there seems to a tendency to turn on the hype engines long before the conlusive data comes in. I've been reading 'Popular Science' for over thirty years now. And I have an affectionet nick name for it: "Popular Science -fiction"

Passing up systems that aren't perfect but are workable now in the hopes of having something much better shortly down the road is, in my opinion, always a risky endevevor. And, in this day and age, with the cheap oil (and Natural gas) about to run out, it can be a fatal one.

To better understand the issues at hand, I am trying to teach myself physics.
They don't call it HARD science for nothin'.

Bob