Re: The Hydrogen Slush Technology Facility

On May 5, 12:50 pm, American <samuelran...@xxxxxxxxxxx> wrote:
Lately I've noticed that the Air Force still has an ongoing project
for Slush Hydrogen Production. There are also patents on the
production method, apparatus, generator, as well as the Transfer Study
done at the NASA K-Site Test Facility.

How soon are the plans to implement this industry?

Slush Hydrogen Transfer Studies at the NASA K-Site Test Facility:

ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/
19920016714_1992016714.pdf

Spray-freeze slush hydrogen generator - Patent 5402649:

www.freepatentsonline.com/5402649.html

Slush hydrogen production method and apparatus - US Patent 6758046:

www.patentstorm.us/patents/6758046-description.html

Self-powered slush maintenance unit - US Patent 5301510:

www.patentstorm.us/patents/5301510-description.html

Aren't the "pellets" manufactured in these facilities comparable
to ones that could be used in a pulsed propulsion design?

- Just REALLY curious HERE...

American

Slush programs I have seen at NASA's Cleveland facility makes
something that looks like hydrogen milkshakes. The ice in this case
is MORE dense than the liquid, so its not the same as water ice which
is less dense. Also, there's a version where solid methane is mixed
into the liquid hydrogen, which is far far denser.

The most technically interesting part is that by setting the methane/
hydrogen ratio you can control molecular weight and energy very
precisely and with it the specific impulse of an engine. Since the
specific impulse and power of an engine are related to thrust, you can
have a higher thrust with the same mass flow rate at lower specific
impulse than you can at a higher specific impulse. Increased fuel
density helps too if you 'volumetrically limited' which many pump
designs are.

That's why during lift off strap-on SRBs make sense - which are then
quickly dropped.

One thing you can do with a methane/hydrogen slush is let the slush
stay low in the tank and blow it out first - with Isp and thrust
following a pre-programmed pattern - fixed by the density profile.
There used to be a treat called a 'push-up' where the icecream was
pushed out of a cardboard cylinder with a cardboard circle at the end
of a stick. Same thing here - the high density stuff comes out first
and get gradually lighter as the tank empties. This gives you an
almost ideal 'goddard trajectory' with very little engine adjustment.
You just turn it on full bore and go. It makes the engine lighter,
simpler, and hopefully, in quantity, less costly.

Fun with fuel engineering.
.

Relevant Pages

  • Re: Sir Frank Whittle
    ... >> The consensus is that von Ohain never saw the patent, ... > I am not so sure about your claim that von Ohain never saw the patent, ... > or that his engine worked earlier. ... Ernest Heinkel who hired both and they began developing with full ...
    (rec.aviation.military)
  • Re: Green Steam Engine
    ... irrelevant to the patent, which is just the bendy bit. ... thing is that it might just be novel enough to gain a patent, ... Ive not built a swashplate engine, but I cant see how you even need ...
    (uk.rec.models.engineering)
  • Re: Sir Frank Whittle
    ... > The consensus is that von Ohain never saw the patent, ... I am not so sure about your claim that von Ohain never saw the patent, ... or that his engine worked earlier. ... Hans von Ohain, whom I know quite well, was the first German engineer ...
    (rec.aviation.military)
  • Re: Green Steam Engine
    ... irrelevant to the patent, which is just the bendy bit. ... trying to invent the IC engine, the drive system wasn't the novel part ... Ive not built a swashplate engine, but I cant see how you even need ...
    (uk.rec.models.engineering)
  • The Hydrogen Slush Technology Facility
    ... Spray-freeze slush hydrogen generator - Patent 5402649: ... Slush hydrogen production method and apparatus - US Patent 6758046: ...
    (sci.space.policy)