reply to post by lpbman
On a technical basis liquids can DEFINITELY compressed...please note
at the bottom of the Marianas Trench at 6.8 miles below sea level
the pressure of the water is 108.6 MPa (15,751 PSI), or over one
thousand times the standard atmospheric pressure at sea level.
This DOES NOT MEAN that the VOLUME of water at the bottom
is 1000 times greater than at sea level, but there IS SOME volume
compression so I must respectfully disagree that liquids cannot
be compressed.
The equation is:
An increase of pressure by 1 atmosphere (= 1013mbar = 14.7 psi)
causes a decrease of the water volume by 5.3*10-5 of the original volume.
If my math & physics is correct, water will compress by a
volumetric factor of 0.46 under 1 GPa of pressure?
which at 2000 PSI will compress only a tiny number
of fractional percentage points in volume at 2000 PSI.
So on this basis, WATER can be technically
considered to be nearly uncompressible.
HOWEVER, since JP8 fuel is a less dense liquid than water,
compressibility would be greater, on the order of about 1.3:1
(if my admittedly shaky math is correct) volume-wise at
high pressures in excess of 2000 PSI (some carbon fibre tanks can
take 5000 to 7000 PSI!) so fuel compression IS a viable option
for some liquid fuels.
The possibility of Compression Ignition of the pressurized fuel stream
would NOT be a safety problem IF multi-stage compression valves
are used. I expect that OTHER JP series fuels might be even lighter
and could possibly be even more compressible.
Yes, the generally LOW compressibility of MOST liquids would be an issue,
but much like the SCUBA gear I have, MULTI-STAGE
compression/decompression valves can be used to COMPRESS or
DECOMPRESS a liquid fuel to a desired pressurization and volume
reduction/expansion point depending upon the inherent strength
of the fuel tanks and inherent compressibility of the liquid fuel.
It's a problematic engineering issue, but NOT an insurmountable one
since the limiting factors are the tanks themselves and the hoses and fittings.
The pressurization of the fuel DOES have one added benefit of helping
fuel vaporization upon expansion which could account for an increase
in horsepower OR an increase in efficency and therefore
an increase in final operating range.
Again, for extending the current range of a C130 aircraft using
highly pressurized fuel system IS a viable (if unorthodox) solution
to keeping the internal storage volume (and carrying capacity)
of a Jet-engined Warthogged C130 to within an acceptable limit.
The wings are VERY sturdy on a C130 and the wing structure could
definitely take the increase in strain. If THERE IS an issue
with the wing structure, it is suggested that a HIGHER GRADE of
aluminum be used for the wing and engine nacelle supports.
Such a CAD/CAM redesign and wing load recalculations wouldn't
take more than 2 months, so there is NO NEED for a complete
re-design, only a re-calculation of strain loads in critical
areas and a subsequent use of better quality (i.e. stronger)
aluminum struts and supports.
And if my recollection of actually sitting in a C130 is correct,
and seeing a real F35, I seem to remember that the F135/F136 engines
are only slightly larger volume-wise than the C130 engines and
actually LIGHTER than the Allison T56-A-15 engine C130 engines.
My opinion is still that the C130 COULD BE converted to a viable
Warthogged Ground Support role aircraft for a final price of
around 32 to 37 million dollars which is STILL a heck of a lot
cheaper than a B2 bomber.
It would be interesting to see if any Lockheed honchos are reading
this thread and hopefully getting some idea that this avenue might
be worth taking a look at!
And I have a suggestion for a name for this new craft....
Ground Support & Attack 130 ...or... GSA-130 Scorpion
cuz it Strikes Quickly and it STINGS HARD !!!!