Exotic Fuel for Aircraft and Rocket

[Michel Van]

I found in Robert L. Forward novel "Saturn Rukh"
this Synthetic Fuel: metastabil Helium NHe64*

know someone about this is a real proposal or is this pure Sci-Fi ?
(Forward had Habit to put proposals in his novels)

the idea of metastable helium is this:
Three helium atoms are aligned in a metastable state.
When it reverts to normal state it releases 0.48 giga joules per kilogram.
only problem is that it tends to decay spontaneously, with a lifetime of a mere 2.3 hours.

in "Saturn Rukh" they solve those problems.
by aligned 64 helium atoms around one nitrogen atom with laser
the Fuel look like blue mercury with densty of 13.5 tons/m3
heat up to 2200° kelvin, NHe64* disintegrated and release energy
isp is 3058 sec

Forward quote a George Phillips from
National Institute of Standards and Technology (NIST) in Boulder, Colorado
and his paper "The Properties of NHe64*"

 

[Orionblamblam]

I found in Robert L. Forward novel "Saturn Rukh"
this Synthetic Fuel: metastabil Helium NHe64*

know someone about this is a real proposal or is this pure Sci-Fi ?

Half-and-half. Metastable propellants provide all kinds of potential, but it's largely theoretical. Sometime in the mid/let 90's there were studies of N20... not nitrous oxide, but Nitrogen-twenty. Basically a buckeyball composed not of carbon but of nitrogen. The story was that the stuff would hold together, and could contain within the buckeysphere other metastable propellents, but if you taunt the Happy Fun Buckeyball, it would explode and provide all kinds of impulse.

Problem is, I don't think anyone has figured out how to manufacture and store the stuff on an industrial scale.

 

[Michel Van]

Half-and-half. Metastable propellants provide all kinds of potential, but it's largely theoretical. Sometime in the mid/let 90's there were studies of N20... not nitrous oxide, but Nitrogen-twenty. Basically a buckeyball composed not of carbon but of nitrogen. The story was that the stuff would hold together, and could contain within the buckeysphere other metastable propellents, but if you taunt the Happy Fun Buckeyball, it would explode and provide all kinds of impulse.

Problem is, I don't think anyone has figured out how to manufacture and store the stuff on an industrial scale.

Oh that's new to me !
there were also idea to use C60 Buckyball as rocket fuel, as replace Kerosene
or make from C60 a "super hydrocarbon" Fuel
but nobody has figured out how to manufacture that stuff

i remember vague of a USAF program for new Fuel
Atomic hydrogene pebbles in pool of liquid helium
but no one has figured out how to pump the Pebbles into Engine.
with out draining the Helium pool

 

[KJ_Lesnick]

You mean attach carbons to the buckyball?

 

[Michel Van]

make from C60 a "super hydrocarbon" Fuel

You mean attach carbons to the buckyball?

yes. mostly hydrogene or hydrocarbon molecules
there was also the idea to fill up in C60 sphere with fuel

a new form Nitrogen can become intresting for new fuel or explosives
Polymere Nitrogen
at pressure of 110 GPa and temperature of 2000°K its form a metastable "diamond"
do to his high instability Polymere Nitrogen is 5 time powerfull as today best Explosives!

more here
Eremets, M.I., A.G. Gavriliuk, I.A. Trojan, D.A. Dzivenko and R. Boehler
Single-bonded form of nitrogen
Nature Materials, August 2004; published online 4 July 2004, http://dx.doi.org/10.1038/nmat1146

original German Announcement by Max-Planck-Gesellschaft
http://www.mpg.de/bilderBerichteDokumente/dokumentation/pressemitteilungen/2004/pressemitteilung200408022/index.html

 

[Simon666]

I found in Robert L. Forward novel "Saturn Rukh"
this Synthetic Fuel: metastabil Helium NHe64*

know someone about this is a real proposal or is this pure Sci-Fi ?

Never heard of metastable helium NHe64*, I had heard of the Helium-IV-A form before, so thanks for the interesting find. Problem with these things is usually the short half life. When googling also found this patent and this patent.

Metastable Helium Rockets

Metastable substances are materials that exist in a long-lived excited molecular state. Metastable Helium is one such substance, comprised of a Helium atom with two electrons, one in the first orbital level and one in the second orbital level. The electrons have parallel spin properties. The molecule is balanced on a knife's edge of quantum forces. The electrons want to enter into the ground state (where both electrons occupy the first orbital level) but are forbidden because of the forces acting upon them from their locked spin states. The atom can remain in this state for a mean time of 2.3 hours, but just a small input of energy (from jostling, molecule formation, electromagnetic forces, etc.) will send it over the edge into its ground state, resulting in a large release of energy, about 114 kilocalories per gram, or roughly twice the energy of the most powerful conventional chemical fuel, atomic hydrogen.
Solar boiler concept; photo courtesy of NASA

Solar boiler concept; photo courtesy of NASA

Metastable helium can be manufactured by several methods. Absorption of photons via laser or particle beam can excite the atom to its metastable state.

But the true problem with metastable helium is not in obtaining it, but in storing it. The 2.3 hour limitation only applies to a completely isolated atom; metastable helium packed in with anything else, even other helium atoms, will result in jostling and it losing its metastable state in a fraction of a second.

Research is being conducted to see if metastable helium can be formed into a room-temperature solid if bonded with diatomic helium molecules, made from one ground state atom and one excited state atom. This solid, called Helium-IV-A, can in turn be used as a solid rocket propellant. Simply heating the fuel is enough to release the energy, so an oxidizer is not needed. These rockets would produce a specific impulse of about 2200 seconds—compared to the 450-second specific impulse for modern liquid hydrogen-oxygen rockets—and would have enormous thrust capabilities, on the order of 31,000 meters per second, matching types of proposed plasma and fusion rockets.
bookcover

Robert Forward, in his fiction novel Saturn Rukh, suggested bonding 64 metastable helium atoms to a single excited nitrogen atom, forming a stable super-molecule called Meta. Whether this is possible remains to be seen. However, as the Meta fuel is much purer than the Helium-IV-A form above, it might allow a metastable helium rocket's specific impulse capabilities to jump to around 3150 seconds.

 

[Lauge]

Courtesy of http://www.projectrho.com/rocket/rocket3c2.html:

Meta-helium He*: SPIN-POLARIZED TRIPLET HELIUM. Three helium atoms are aligned in a metastable state. When it reverts to normal state it releases 0.48 gigjoules per kilogram. The trouble is that it tends to decay spontaneously, with a lifetime of a mere 2.3 hours.
--------------------------------------------------------------------------------
Meta-helium He IV-A: DIATOMIC METASTABLE HELIUM. One normal and one excited helium atom are paired to form a stable solid.

The trick is to keep the touchy stuff from exploding prematurely and destroying the spacecraft. The fuel is stored in a resonant waveguide.

According to the table on the above site, Meta-helium He* should give a (theoretical) Isp of around 4300 s (roughly ten times that of a good chemically fueled engine), with Meta-helium He IV-A giving about half that. But, as Orionblamblam points out, even if someone found out how to make and store the stuff, it would tend to go BOOM with little if any provocation.

Anyway, fuggeddaboutit and go with antimatter. Now there's a fuel that provides fun & games for the whole family.... ;D

Regards & all, and a Happy Easter,

Thomas L. Nielsen
Denmark

 

[Pioneer]

What about the study for a fuel for the USAF "Weapon System 110A", which would become the North American XB-70 Valkyrie bomber. ???
Graet study went into Boron-enriched "Zip Fuels", which improved the energy density of the fuel by about 40%.[6] Various US government agencies had been experimenting with zip fuels for some time, and they believed that once the problems they were having were worked out, zip fuel would become almost universal for high-speed aircraft. Although the advantages of a zip fueled aircraft would not be as great as those of a nuclear powered one, it would offer a real performance increase and was a relatively straightforward development of existing engines and fuels.
Zip fuel was to be used in the afterburners to improve range by 10% to 15% over conventional fuel.

Regards
Pioneer

 

[Michel Van]

one reason to kill the Zip-fuel project was is costs
the other reason was Zip-fuel made gruesome things to Jetengine

the Turbine, combustion chambers, afterburner tube
were covert with Extremely poisonous adhesive similar material !

i will post more on Zip fuel next Tuesday

 

[Michel Van]

ZIP FUEL or High Energy Fuels HEF
was a high-priority, top-secret program in both the USAF & USN during the 1950s.

those High Energy Fuels were study:
HEF-1 ethyldiborane
HEF-2 propylpentaborane
HEF-3 ethyldecaborane
HEF-4 methyldecaborane
HEF-5 ethylacetylenedecaborane

planed use of HEF

original The B-70 design had J93-GE-5 engine
with HEF-3 in the afterburners fed from separate fuel tanks.
The BOMARC missile program also considered use of HEF in its ramjets.
The Navy also made elaborate plans to use and store HEF or "zip fuel" on carriers.
Also to use the boron rich fuel as absorber of neutrons, in nuclear-powered airplane

Advantage:
ZIP gave about 140% of the energy of JP-4 per unit weight & volume.
Disadvantages:
they were very expensive to make and store, left (extremely toxic) solid deposits
in tailpipes, Turbine

the Program was cancelled in August 1959

most date from WarbirdTech Vol. 34' by the indispensable Dennis R. Jenkins.


a Renaissance of Boron Fuel ?

Tareq Abu-Hamed from University of Minnesota
Proposed Water and Boron as Fuel for Aircrafts
so called "on demand hydrogen production"

water react with Boron form Boronoxide and Hydrogene
the Hydrogene is used for Jetengine or fuelcell -> electro motor
while the Boronoxide is stored and recycled in a Plant at Airport

Tareq Abu-Hamed study also Water and Sodium reaction for hydrogene production.

source:
Energy and our Future by Robert Das and Rudolf Das
ISBN 9789043911337
page 48-51

 

[CJGibson]

Evening All,
I'm working on contrail reduction and in a USAF Geophysics Research Department report from 1963 have come across a low hydrogen fuel designated 'TEF-1'.

It was ultimately used in the Ryan Model 147 Lightning Bugs over Vietnam

What is it?

Chris

 

[CJGibson]

Trail Elimination Fuel No.1 apparently. High in aromatics.

Chris