thinking of running car on petrol & water mix

grimsalve

What about pouring a bottle of Actimel into the tank every day?

hartcjhart

jase1 wrote: »

What interested me about the Mythbusters debunking of rubbish like this was the fact that the petrol engine was running along perfectly happily on a continuous supply of hydrogen gas.

Surely this means that the only difficult piece of the puzzle to overcome (and I recognise that this isn't exactly trivial) is putting together an infrastructure to deliver hydrogen to vehicles, and store it safely. Was there really any need for Honda's hydrogen car concept?

The means to create hydrogen ecologically and cheaply is readily available. Nonsense like the above (using x energy to create it from water only to get something like x/2 energy back out from it) is stupid, but in principle the science does seem to be fundamentally sound.

I believe that there are 'Hydrogen' fuelled buses running in London

Strider590

Stuff like this is probably the invention of the motor repairs industry.......

It's also amazing how people think petrol goes straight into your engine!!!!!!!!!

Petrol is more of an accelerant, your actually burning more air than petrol!! It's actually something like 15 parts air to 1 part petrol......
Too much fuel and it'll fail to burn properly, too much air and it'll burn too aggressively and cause overheating.

Petrol as a liquid is not flammable at all, you could set up an electrical spark under the surface of petrol and it would not ignite, BUT fuel vapour is extremely flammable thanks the presence of oxygen at the surface.

It's a mixture of air and fuel vapour that is compressed, trying to burn water is the stupidest thing i've ever heard.... It would simply make it harder to ignite the fuel/air mixture, this would result in older cars (carburettors) stalling or newer cars (fuel injection) trying to force more fuel into the cylinder to compensate.
You'd just get a really lumpy ride and reduced fuel efficiency..... That's if the car could continue to run at all!

jase1

> trying to burn water is the stupidest thing i've ever heard....

Well obviously, but using hydrogen as a vector for energy produced by other means is established reality. What is happening here is the usual "a little knowledge is a dangerous thing" spiel; you can turn water into hydrogen and oxygen fairly easily with an energy source (the petrol) then convert it back, producing energy in the process, but you're not gaining anything.

But manufacturing the hydrogen from renewable sources, or nuclear, is probably the future if it can be stored efficiently. Yeah you lose some efficiency but if we could get to the point where renewables were providing all our energy, who would really care about some lost energy as long as we could cover it?

shaun_from_Africa

trying to burn water is the stupidest thing i've ever heard.... It would simply make it harder to ignite the fuel/air mixture

When you have water injection on engines, you are not trying to burn the water. You are using the water/alcohol mixture to help cool the petrol/air mix (making it more dense), and using the expansion of the water vapour to help create more engine output power.

As I stated earlier, this was fairly common on fighter aircraft in the war, and has been tried and tested on some turbine engines.


None of this will help on the fuel consumption as suggested by the OP. It is simply a way to get more engine performance for a short time, and works best at high air temperatures and when the engine needs maximum power for a short time.

kaya

exup wrote: »

if you couldnt compress fluids than an internal combustion engine wouldn't work at all - in fact not many things would work, as air (any gas in fact) is also a fluid.
Perhaps you meant you can't compress liquids (not very much anyway).
I remember water injection being talked about a few years back with a multipiston rotary engine which could use very low octane rated fuel (even mixed with water) Think it was Brian Crichton (Norton race team) who designed it.

I have had water injection in my car, but only when the head gasket failed.

liquids can be compressed, fluids can not, if fluids could be compressed then hydraulics would not and could not work, how on earth did you come to the conclusion that air is a fluid? oxygen, nitrogen etc are gasses , when compressed they become liquids (liquid nitrogen/liquidoxygen/liquid petrolium gas), the stuff in your bbq gas bottle is liquid because it is compressed(lpg), when you release it to atmosphere it becomes a gas again, what engine do you know of that runs on a fluid? or what hydraulic do you know of that would run on liquid? (its called hydraulic FLUID for a good reason), perhaps you would allow me to fill one of your cars cylinders with water to prove your point?

Strider590

jase1 wrote: »

> you can turn water into hydrogen and oxygen fairly easily with an energy source (the petrol) then convert it back, producing energy in the process, but you're not gaining anything.

This reminds me of something.....

Water = H2O

Hydrogen molecules x2, oxygen molecules x1

Even the application of heat cannot break these molecules apart, it simply produces water vapour which then condenses on the nearest cold surface.

The way the molecules combine disables both as far as combustibility is concerned. Otherwise water would be the most flammable liquid on the planet and we'd have to turn off our mobile phones for sake of turning the entire planet into a giant fireball.....

djheath

Strider590 wrote: »

This reminds me of something.....

Water = H2O

Hydrogen molecules x2, oxygen molecules x1

Even the application of heat cannot break these molecules apart, it simply produces water vapour which then condenses on the nearest cold surface.

The way the molecules combine disables both as far as combustibility is concerned. Otherwise water would be the most flammable liquid on the planet and we'd have to turn off our mobile phones for sake of turning the entire planet into a giant fireball.....

You can split h2o into its component parts very easily using electrolysis, which is what I think Jase1 is getting at - i.e using the car engine to charge the battery to use an electric current to split water, to then feed into the engine to burn.

However, as stated, the engine out would be considerable less than the energy in and you would end up burning more petrol than if you didn't bother doing it in the first place.

Strider590

^^ That's not what the OP suggests though..... OP literally suggests burning water vapour lol

Inactive

birkee wrote: »

Fill your petrol car with Diesel and find out, or vice versa.

This has got to be urine taking hasn't it?

He will only put it in his fuel tank if it is.;)