On Thu, 31 Oct 2013 qbert@xxxxxxxxxxxxxxx wrote: > Like I first posted right after the original post this is just a > marketing stunt for a system that has been in the half baked category > for years. It's been touted as everything from a way to increase MPG for > you car to creating the next health miracle by bubbling it through > water. It's been called HHO and all sorts of other names but it just an > electrolyses the does not separate the H2 and O2 that comes off the > anode and cathode. I think you didn't read it carefully. Yeah, there is a lot of snake oil about Brown's gas, but this is a different and more refined form of snake oil. :-) Note that they explicitly refer to generating the H2 and O2 *separately*, and to control of mixture ratio. This is a more ordinary oxyhydrogen torch supplied by a more ordinary electrolyzer. Which is not a ridiculous idea, if you overlook the elephant in the room, that being the huge electric power requirement. > But at 60psi you would need an awful big container to run any type of RCS > system so storage is out and even the jewelers unit which produces 30L of > gas an hour is heavy 18kg and requires 24V at 4.5amps to operate. That's > just a little big for a Cube Sat. As I noted, people have successfully fired such thrusters, from storage (with the GOX and GH2 stored separately!). And at least the Tethers Unlimited system specifically *is* aimed at nanosats. The key is that the GOX and GH2 don't mix except in the thruster (in fact, the key is making very sure of that...). > I do have a question after all of that, Since they have been running these > things at 60psi with safety precautions tied in, Is there a pressure at which > the gas becomes unstable and or just turns back into water? No, if you're sufficiently suicidal, you can put GOX/GH2 mixtures under quite high pressure without causing a reaction to start. There have been some serious accidents that have started with accidental production of high-pressure GOX/GH2. The problem is that you're then dealing with a horribly sensitive high explosive; on at least one occasion, simply trying to vent such a mixture slowly resulted in a fatal explosion. Henry Spencer henry@xxxxxxxxxxxxxxx (hspencer@xxxxxxxxxxxxx) (regexpguy@xxxxxxxxx)