hydrogen ugly stick

[Sicarius]

can anybody tell me if the revised 11/26/06 ugly stick would work for using a hydrogen fuel and would i have to reduce the size of it

going to try this because i have no welding equiptment at the moment

[toakreon]

How well does this "Ugly Stick" design work? Strikes me it might serve for me as well, as an "established design" to get running before investing in welding kit for the "Squirrel".

John

[Mike Everman]

It works fine. Not the greatest, of course, but great fun. 1 lb thrust or so; about standard for a straight piper this size. There's been half a dozen builds.
Throw on the two 90deg elbows to bend it.

I don't see why you couldn't run it on hydrogen, but why so stuck on that fuel?
Yes, it's faster flamespeed would allow you to scale it down a lot. Perhaps you go half, with a 1" pipe CC. Sounds like good fun.

[Sicarius]

i am stuck on that fuel because all my fuel source is electrolized tap water
stored in two different tanks in a compressed state

one part oxygen
two parts hydrogen

i dont even need to pay for gas it runs off the mains

[Mike Everman]

i dont even need to pay for gas it runs off the mains

Electrical mains you don't have to pay for?

[Sicarius]

i kind of have to pay for the power but i am trying to get some more solar panels to collect more energy so it can keep going during the night[/i]

[Jim Berquist]

Please tell me I'm wrong.

Did you say 1 part oxygen 2 parts hydrogen. You are not compressing to two together are You??? :{

Jim

[Mike Everman]

no he's not.

[Jim Berquist]

I would like to see what type of vessels he using for the electrolysis process.

Jim

[heada]

One other option would be to use atmospheric oxygen. Burn the H2 in the air and it will consume the O2 from the atmosphere. No need for the 'one part oxygen" as the natural world will provide that for you (unless you gain significant altitude)

Something that might make the legal group a little easier as well since if you provide the oxidizer, its considered a rocket engine but if you use atmospheric oxygen its just a jet engine (pulse jet, ram jet, turbo-fan, etc)

Also, for the detractors of using hydrogen as a fuel, LH2 has the highest ISP that I know of (ISP = basically bang per weight) and is the ideal fuel for most rocket engines (LH2 + LOX = major thrust) but that is in the liquid phase and cryogenics are not for the faint of heart (or a small budget).

This also imposes a safety issue if you're not careful. If there is a hydrogen leak and it ignites, it will consume all the near-by O2 and you'll be hard pressed to find some to breathe with (besides just surviving a large fireball)

-Aaron

[larry cottrill]

LH2 has the highest ISP that I know of (ISP = basically bang per weight)

Aaron -

That's part of the problem, though - you may have large energy per unit weight, but on the other hand, you have the lowest density material in the universe. A 2000 PSI cylinder contains several kg of air, while the same cylinder pressurized at 2000 PSI full of hydrogen will have (I'm guessing) less than a kg of mass of hydrogen in it. In the liquid state, as in a rocket, it's still pretty low mass for the volume carried. In a rocket, that's probably not a big deal, but in an aircraft bulk can be just as hard to design for as weight.

Of course, that doesn't mean it shouldn't be tried. I think hydrogen is a great choice for a fuel in a lot of ways - the main problem I have with it is the safety aspect. It is darned hard to prevent leakage with hydrogen, and you need some kind of detector to divulge an accumulation, since it is completely odorless - AND, it is ready to burst into flame (explosively!) over such a wide range of mixtures. I think that's the real issue - there's bound to be some way to make pure hydrogen cheaply enough to use (it's already used as a fuel gas for some flame-cutting operations, for example - as in my old underwater cutting torch).

L Cottrill

[Jim Berquist]

I just got off the Google thing and it seem that I am way behind the learning curve on this one. People are using Hydrogen for cooking and heat. Given the price of propane , I think I will investigate more. Need to check out the start up cost for a cheap??? Safe system....

Jim

[heada]

density of GH2 = 0.0899 g/L
density of GO2 = 1.429 g/L
density of G(air) = 1.2 g/L (mostly made up from 78% GN2 and 21% GO2)

So yes, the amount of GH2 you would get from a given tank size will be much less. When liquefied, the numbers come closer together and become more reasonable but then again, you'll be dealing with cryogenics and that is when things stop being simple.

One of the benefits of being so light is that if there is ever a leak, it will go up in to the atmosphere fairly quickly which is not the case with most hydrocarbon fuels we use. They tend to pool near the ground but lucky for us the air-fuel ratio is also sensitive enough that it lowers the risk. The soapy water trick is normally enough to detect a leak for just about anything (GH2, GO2, LPG, Kerosene, etc)

-Aaron

[Jim Berquist]

I have seen pressures up to 5000 psi. Most units available on the net run 250 psi using propane tanks or simular. That would be like a one use per charge thing. One dinner. One hot water burn. One trip to town 3 miles away. I could live with that!

Jim