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-   -   water as a fuel in cars (http://www.physicsforums.com/showthread.php?t=144105)

saad ahmed khan Nov16-06 07:54 AM

water as a fuel in cars
 
hello every one
while surfing i came across this site
http://netmar.com/~maat/archive/feb2/carplans.htm

it has some plans and drawings for adapting an ordinary petrol/gasoline engine to run on water

i just started university as a mechanical engineer may be i will take this as a final year project

but first i wish to know reviews from you people as well as construction tips ideas problems etc i donot have much experience with engines as i cant get opportunities or time to visit garages and auto shops, though i have a little bit of experience in electronics.

i would like all of you to help me and yourselves
think about the savings we could make

think clean think water

thanx in advance to any would be helpers

Mech_Engineer Nov16-06 08:36 AM

This has been discussed several times, the definitive answer is that water is a BYPRODUCT of a combustion process, not a fuel for one. There is no way to make a combustion engine to run off of water unless you first separate it into hydrogen and oxygen, which takes a lot of energy. Energy can be stored using water through electrolosis, but any energy you get from the burning of hydrogen and oxygen must first have been put into it.

Running a conventional combustion engine off of hydrogen by itself is not a very good idea either because hydrogen is very low in energy content, meaning any car running off of it will produce little power and not get very good mileage.

There is no significant amount of energy available in water by itself for use in a vehicle.

Danger Nov16-06 09:17 AM

I read as much as I could of that link... enough to know that the site is a crock. They are indeed proposing an on-board electrolysis unit controlled by the throttle. Somewhere along the line, they forgot that the electricity needed for the process has to come from somewhere, and it can't be sustained by the engine through an alternator system.
They also are using figures and even definitions that are out of whack by miles. Do youself a favour and block that site from your browser.

Mech_Engineer Nov16-06 10:42 AM

I want to see the citation for the site's claim that the Department of Energy says there is up to 40% more energy stored in water than gasoline :rolleyes:

carp Nov16-06 10:43 AM

I thought of this idea when I was 15 years old, and It still didn't take long for me to realize that this idea is a load of BS. There are tons of sites just like the one you linked to and absolutely none of them have much basis on real science. Don't waste your time.

carp
PropulsionAccess.com

russ_watters Nov16-06 11:44 AM

You do not want to work on this as an important ME project. It is crackpottery.

brewnog Nov16-06 12:01 PM

If you've started a degree in mechanical engineering, you really should know the answer to this yourself. Not only is it the first thing you get taught in thermodynamics, it's basic common sense. Which university are you at?

Danger Nov16-06 05:09 PM

Quote:

Quote by Mech_Engineer
I want to see the citation for the site's claim that the Department of Energy says there is up to 40% more energy stored in water than gasoline :rolleyes:

It's either just totally made-up, or some idiot confused 'specific impulse' with energy. Hydrogen and oxygen burning is more efficient than gasoline and oxygen. I have no idea what the actual SI numbers are, though. I know that the Saturn V with kerosene and oxygen was something like 450 seconds, and the NERVA with pure hydrogen (no oxydizer) at 2,700 degrees C. put out about 1,100 seconds (to the best of my feable memory capacity).

Mech_Engineer Nov16-06 05:36 PM

I'm quite sure the entire thing is made up without any real engineering work having been put into it. :rofl:

Danger Nov16-06 07:06 PM

Most likely. :rolleyes:

saad ahmed khan Nov17-06 04:36 AM

thanks for those replies
 
ok guys
i myself felt a bit unsure about this project
so i am waiting till these guys at the website come up with solid working proof pics and videos

better still i should contact the mythbusters from the discovery channel
they could solve this problem

however i came across a video on another forum abt cars its of a corrolla that uses water as a fuel problem is its not in english so i dont know what to make of it, and i have the video but dont remember where i got it from
can i upload it though that would take a heck of a long time me being a poor dialup user :(

about the fuel cells. they are supposed to work for electric vehicals only right that use electronic motor and no engines. i could take up those project but an electronic car is expensive to build
abt the project i am not serious, heck i just started university and will learn more.
also can you point me to websites about car engines etc, i cant get first hand info abt this like electronics. i can buy electronics components easily but not engines

thanks for enlightening me

brewnog Nov17-06 07:39 AM

Saad, don't ever let yourself be fooled into believing that water is a fuel. It is not. You don't need Mythbusters to show you that water is an exhaust product of hydrogen combustion, not a fuel source.

Fuel cells are well understood. These run using hydrogen as fuel; a simple google search will yield many useful sites.

Danger Nov17-06 08:55 AM

If you get Discovery Channel, then there's a fair chance that you also get Spike. Start watching the Power Block series (Muscle Car, Horsepower, Xtreme 4x4, etc.). It can teach you a lot about engines as well as other aspects of vehicular design. It wouldn't be my first choice for a definitive education, but it's certainly a decent start.

paddy-boy66 Nov17-06 10:11 AM

surely you can use some of the engines heat energy to heat water in to steam and run some of the car off steam.
www.steamcar.co.uk/

brewnog Nov17-06 10:28 AM

Course you can paddy. But the water there is not fuel, it's just a medium by which to transfer heat.

saad ahmed khan Nov17-06 11:50 AM

did you guys see the circuit that is enclosed in the plans
can it really do what it is meant to do i.e.break water in to hydrogen and oxygen can any one verify that circuit or test it

also i just wanted to ask if suppose that we had hydrogen and oxygen in the gas form then could a mixture of it be used to run a car, not keeping in mind any disasters or other impacts

banerjeerupak Nov17-06 11:55 AM

Well the whole thing is a hoax, but the concept to using water for the heat transfer is the same as used by Crower in his six stroke engine....

carp Nov17-06 12:08 PM

It is possible to break water into hydrogen and oxygen using electricity. It is called electrolysis. The setup used to do this is simple. You simply need a source of electricity connected to two electrodes (and an electrolyte dissolved in the water to conduct the electricity).

As for your second question, yes, it is possible to run an engine off of gaseous hydrogen and oxygen, although it is technically challenging.

carp
PropulsionAccess.com


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