New propulsion sytems for ships

[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.

[Guillermo]

I have posted before something about our 'Peixe Verde' project in Spain, which is devoted to find better and more efficient propulsion systems for fishing vessels. Lately they opened a contest of ideas to that end, which is now in the phase of evaluation. SkySails system was elected one of the twelve finalists.
www.skysails.info

The contest is promoted by the Spanish IDAE (Institute for Diversification and Energetic Savings, of the Ministry of Industry), by The Education and Science Ministry, and by CETPEC (Celeiro Fisheries Technological Centre); CETPEC is the responsible of all organization.
More: http://www.peixeverde.org/peixe_org_...20%20ideas.htm

A test presently being runned is the substituition of gasoline by LPG for the small boats' outboards.

Also the vessel in the photo is being used as a test bench for the use of natural gas and LPG in this kind of vessels.

[StianM]

Originally Posted by charmc

Stian,

but you're wrong about the effects of ethanol's lower energy content.

I newer argued that ethanol don't have lower energy contence. I argued that ethanol mixed in fuel 10% don't reduce the milage by 10% but more like 3%.

Originally Posted by charmc

Diesel fuel has a higher LHV than gasoline, which is why diesels get better fuel mileage.

Even if the value off diesel and gasoline was the same the diesel would still have bether because it can runn leaner.

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,

I know some people still use it on street cars and I think it's also used in rally cross. Some people say it will increase corosion while some say that will only hapend if you use too mutch. I think Alchol evaporating at lover temps than water increase the cooling and it would also increase the octane a litle while is used so it probartly has more positive effect than antifreze only.

I build a water injection system, but newer tested it.
Was it not used in the US in the 70's when the gasoline was a litle too expensive? Think I heard some people used water injection on there cars so they could runn cheaper low octane rated fuels on high compresion engines.

[FAST FRED]

The latent heat of evaporation is far higher fore pure water than for alcohol, so the WATER is what makes water injection work for anti detonation..

In lightly loaded auto engines not too much mileage loss is actually noticed from the 10% blend.

In a Motorhome , square front , "Uphill" every mile the mileage reduction IS the alky percentage, I have 10,000 miles of fuel log to prove it.

Water injection actually cleans most combustion chambers up. The almost explosive creation of steam , and the scouring power of the water is great.

Back in the non detonation computer days , folks with a high compression engine would run the engine (warm) at about 1500 and use a bug sprayer (Flit gun) to pass a quart of tap water thru the engine. Would clean out carbon deposits and hot spots with great ease.

A newspaper under the tail pipe would SHOW the removed chunks.

FF

[brian eiland]

Originally Posted by charmc

... The fundamental aspect is that one gallon of 87 octane gasoline has an LHV (lower heating value, the energy available through normal combustion) of 115,500 BTU's while a gallon of ethanol has an LHV of 76,000 BTU's. That's only 2/3 the energy content.

Sounds like our figures are pretty close. I had posted above, " A gallon of E85 has an energy content of about 80,000 BTU, compared to gasoline's 124,800 BTU (thats an eye opener, huh)"

[charmc]

Originally Posted by brian eiland

Sounds like our figures are pretty close. I had posted above, " A gallon of E85 has an energy content of about 80,000 BTU, compared to gasoline's 124,800 BTU (thats an eye opener, huh)"

Right, Brian. Ethanol can contribute to the diversity of energy sources needed in the future. But the silly, simplistic hype created and promoted by knee jerk environmentalists, politicians, and mass media is counter-productive to the effort to find realistic answers.

[StianM]

Originally Posted by FAST FRED

The latent heat of evaporation is far higher fore pure water than for alcohol, so the WATER is what makes water injection work for anti detonation..

Ethanol evaporate at a lower temperature so it will increase the cooling effect since you can use more fluid without it codensing.

Etanol also has higher octane rating than gasoline so having Etanol in the water for water injection will increase the overall octane.

I read a recomendation to use up to 50% etanol in the mix.

[brian eiland]

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,

FF.

I remember reading of WWII fighter planes that made use of water injection as a sort of Super Charger effect.....when water turns to steam it expands 17,000 times!! So a little mist of water in the combustion chamber should surely raise the force exerted on the piston.

So I googled "WWII fighter, water injection". Lots of material came up including this;
"Water injection is a method for cooling the combustion chambers of engines by adding water to the incoming fuel-air mixture, allowing for greater compression ratios and largely eliminating the problem of engine knocking. This effectively increases the octane rating of the fuel, meaning that performance gains can be obtained when used in conjunction with a supercharger or turbocharger, altered spark ignition timing, and other modifications. Many water injection systems use a mixture of water and alcohol (usually 50/50), partly because the alcohol is combustible, while water is not; in addition, the alcohol serves as an antifreeze for the water. Hence, water injection is also often known as methanol-water injection, owing to the fact that the alcohol mixed into the injection solution is often methanol, CH3OH.


NOTE: Due to its corrosive nature, the alcohol in water injection systems cannot be ethanol. Only methanol and isopropanol are used, methanol being the more commonly-utilised form of alcohol for this purpose due to its higher availability and lower cost than isopropanol.

Water injection is often necessary when adding forced induction to an engine that was not designed for it; the compression ratio of a normally-aspirated engine is too high to cope with more than a very modest boost, even with retarded ignition timing, unless this technique is used.

The system was first used extensively on World War II fighter aircraft to increase power upon takeoff and bring up the service ceiling. A limited number of road vehicles with large-displacement engines from manufacturers such as Chrysler have also included water injection. Saab offered water injection for the Saab 99 Turbo. With the introduction of the intercooler the interest in water injection disappeared, but today, water injection is also of interest because it can potentially decrease nitrogen oxide (NOx) emissions in exhaust. Water injection is primarily used with piston-powered internal combustion engines, but it has also seen use with turbines.

The initial injection of water cools the fuel-air mixture somewhat, which may allow for more mixture to enter the cylinder. But the greater effect comes later during combustion when the water takes in significant amounts of heat energy as it converts from liquid to gas (steam), increasing piston pressure (torque) and reducing the peak temperature with its resultant NOx formation as well as the amount of energy absorbed into the cylinder walls. The duration of combustion is said to be longer. An interesting side effect that has been reported by some is that water injection effectively "steam cleans" the engine interior, resulting in less carbon residue buildup. Glowing hot carbon deposits are a known cause of knocking."

[StianM]

Originally Posted by brian eiland

I remember reading of WWII fighter planes that made use of water injection as a sort of Super Charger effect.....when water turns to steam it expands 17,000 times!! So a little mist of water in the combustion chamber should surely raise the force exerted on the piston.

14,670 times at atmosferic preshure not 17000. It won't increase the preshure in the cylinder at all. The water neads heat to evaporate and that heat will be taken from the combustion air and the air will therfor exspand less. Mixing water in MDO has had some benefits since water drops inside fuel particles will explose as steam once entering the combustion chamber vaporaising the fuel bether.

Originally Posted by brian eiland

Water injection is a method for cooling the combustion chambers of engines by adding water to the incoming fuel-air mixture, allowing for greater compression ratios and largely eliminating the problem of engine knocking. This effectively increases the octane rating of the fuel,

Water will only cool the combustion chamber just like a intercooler, but will not increase the octane unless alcohol is added.

Originally Posted by brian eiland

Many water injection systems use a mixture of water and alcohol (usually 50/50), partly because the alcohol is combustible, while water is not

Alchohols have a rather low energy value so this would not be a main reason.

Originally Posted by brian eiland

Due to its corrosive nature, the alcohol in water injection systems cannot be ethanol

I heard this manny times, but I also heard the same about metanol. I don't know witch one it is.

Originally Posted by brian eiland

Water injection is also of interest because it can potentially decrease nitrogen oxide (NOx) emissions in exhaust.

High preshure and temperature force nitrogene and oxygene to bind into NOx. I know Wartsila has played with this on the Wichmann. Adding larger turbos and intercoolers to get lower combustion temperatures and also ading water trough seperate injectors in the combustion chamber.

Originally Posted by brian eiland

But the greater effect comes later during combustion when the water takes in significant amounts of heat energy as it converts from liquid to gas (steam), increasing piston pressure (torque)

I think they us up to 10% water injection to reduce NOx. With water higher then 5% they get powerloss and only in rear ocations they get a smal power increase.

Originally Posted by brian eiland

An interesting side effect that has been reported by some is that water injection effectively "steam cleans" the engine interior, resulting in less carbon residue buildup. Glowing hot carbon deposits are a known cause of knocking."[/i]

Not really a interesting side effect, manufacturers have used water for a long time (sometimes mixed with ACC Air cooler cleaner) to clean the compresorweel in the turbo and clean the intercooler and the manifoils.

On the exhaust turbine some use rice to sandblast the turbine weel.

[Pericles]

My '96 Volvo T5 is rated at 240 BHP. Newer ones go as high as 310 BHP, from the factory. A Superchip could up the power of my T5 to around 300BHP for about £550, but with 125k on the clock, I think it would have an adverse effect on engine reliability. The point is, the added complexity of water injection, with or without methanol, seems not to offer much, in comparison with some easily installed electronic trickery. The standard intercooler works very well and I have a choice of 95 or 97 octane, but any difference in performance seem negligible to me.

Years ago, Cleveland Discol petrol was available in the UK and it was claimed to contain some 5% alchohol, but did not describe which type.

http://www.honestjohn.co.uk/forum/po...tm?f=2&t=25120

I would always stick Super Discol in the Cortina 1200 company car as it was 5* and somewhat higher than 101 octane. When the maximum speed was 75 mph with other fuels, 82 mph was possible on Super Discol. Very important bragging rights for us, when working as "sales reps".

Now, if E85 both cleans carbon from the combustion chambers and offers a higher octane rating than 97, turbocharged cars would see the greatest benefits even if overall gas mileage might be down a little.

I do not think I would be too comfortable with introducing rice to clean contamination from the turbocharger blades. I guess I'll stick with a very occasional shot of STP or Redex.

Pericles

[Guillermo]

The USA engineer Don Burg (President of Hydro-Air Drives, Inc.) has patented a new concept of ship called SWEEP (Ship with Wave Energy Engulfing Propulsors).
http://www.linkgrinder.com/Patents/S...__7017505.html
"Abstract: Presented is a water propulsion system for ships that enhances the efficiency of both the water propulsor(s) and the ship itself. This is accomplished by location of water inlet(s) for the water propulsor(s) to take advantage of water flow characteristics around a secondary bow of the ship and also proximal a stern of the ship. A primary object is to reduce the energy of the bow and/or stern waves of the ship and hence reduce the ship's wave making resistance. A secondary object is to reduce the frictional resistance of the ship. The water propulsors are preferably electrically driven with built in stator field windings and armatured rotors. A bow oriented water propulsor(s) would preferably have its discharge into a gas cavity in the underside of the ship. Both bow oriented and stern oriented water propulsor(s) would optimally have steering and/or reversing mechanisms."


It significantly reduces the wave drag of high-speed displacement hulls by utilizing the inlet water flow into large water propulsors to engulf or suck in wave energy. The water flow detaches from the sphere at the bow in high drag eddies after following the contour of the sphere inward aft of the sphere's mid-section. In order to maximize its efficiency gains an optimum SWEEP discharges its bow propulsors water jet flow into a raising air layer under the hull. This approach avoids turbulence-mixing losses that would occur if the discharge jet was underwater. The blower power required to maintain the SWEEP's presurized air layer is only a few percent of its propulsive power. (Burg D. Work Boat World 2005 24/8, 20-21)

Following Don Burg's data, a 122 m long SWEEP ship reduces its total resistance between 15 and 20% at 20 knots and 40% at 45 knots.

More:
SWEEP (Ship with Wave Energy Engulfing Propulsors) has been the subject of presentations at ASNE (American Society of Naval Engineers) Day 2005, FERRIES 2005, and is the subject of articles in Naval Engineers Journal and other trade publications. The SWEEP invention promises to improve the efficiency of large high speed displacement hulls such as destroyers and larger military combatants, high speed freighters, and the like. It is the subject of a proposal for government funding by the Military SeaLift Command (MSC) and the Naval Surface Warfare Center (NSWC).

[asfekar]

hi. are there anybody who experienced zodiac rib's overall propulsion efficiency. i will build my first craft. i will use %55 overall efficiency in hydromax. and then i will add %15 machine +sea+propeller margine.
is it true.

[kach22i]

Video:
turns Salt Water into Fuel
http://www.wewin.com/turns-Salt-Wate...Auto-Fuel.aspx

Even if it takes more energy to create the radio waves than you get out of the sea water, you could still burn a navy fleet in the very seas it sails in.

[marshmat]

An interesting concept, to be sure. Whether it's more efficient than the conventional technique of electrolyzing water to get hydrogen and oxygen, we can't know without more data. I'd want to know, for starters, what frequency and intensity the radio waves are. To really understand the process requires a lot more information than can be packed into a quick TV spot.

[charmc]

Originally Posted by marshmat

An interesting concept, to be sure. Whether it's more efficient than the conventional technique of electrolyzing water to get hydrogen and oxygen, we can't know without more data. I'd want to know, for starters, what frequency and intensity the radio waves are. To really understand the process requires a lot more information than can be packed into a quick TV spot.

Right, Matt. The age old question: How much energy does it take to make this energy useful?

I like it, though, out of the box thinking. And as George noted, it would be really cool to zap the ocean around an attacking warship and set it on fire.