Sargon
Nothing to see here
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That is a nice idea!How about "trapped" as the chapter title?
It gives a nice false impression that the trapping will happen to one of the heroic characters^^
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That is a nice idea!How about "trapped" as the chapter title?
It gives a nice false impression that the trapping will happen to one of the heroic characters^^
How about "trapped" as the chapter title?
It gives a nice false impression that the trapping will happen to one of the heroic characters^^
I was greatly amused by the behavior of each new contractor as it
got into the act. The pattern was invariable. First, they would get
themselves a computer. Then, they would calculate the performance
of every conceivable liquid oxidizer with every conceivable solid fuel.
And then they would publish a huge report containing all the results
of all of these computations. And to the surprise of nobody who had
been in the business any length of time (we had all made these calcu-
lations for ourselves years before) everybody came out with the same
numbers and recommended practically identical combinations. Thus,
the fuel grains recommended by three different contractors, Lock-
heed, United Technology Co., and Aerojet, comprised: (...)
Just as Wharton was starting his IBA work, there occurred one of
the weirdest episodes in the history of rocket chemistry A. W. Haw-
kins and R. W. Summers of Du Pont had an idea. This was to get a
computer, and to feed into it all known bond energies, as well as a
program for calculating specific impulse. The machine would then
juggle structural formulae until it had come up with the structure of
a monopropellant with a specific impulse of well over 300 seconds.
It would then print this out and sit back, with its hands folded over
its console, to await a Nobel prize.
The Air Force has always had more money than sales resistance,
and they bought a one-year program (probably for something in the
order of a hundred or a hundred and fifty thousand dollars) and in
June of 1961 Hawkins and Summers punched the "start" button and
the machine started to shuffle IBM cards. And to print out structures
that looked like road maps of a disaster area, since if the compounds
depicted could even have been synthesized, they would have, infallibly,
detonated instantly and violently. The machine's prize contribution to
the cause of science was the structure,
(snip chemical compound structure)
which it confidently attributed a specific impulse of 363.7 seconds,
precisely to the tenth of a second, yet. The Air Force, appalled, cut
the program off after a year, belatedly realizing that they could have
got the same structure from any experienced propellant man (me,
for instance) during half an hour's conversation, and at a total cost
of five dollars or so. (For drinks. I would have been afraid even to
draw the structure without at least five Martinis under my belt.)
All sorts of efforts were being made, during the late 50's, to increase
propellant densities, and I was responsible (not purposely, but from
being taken seriously when I didn't expect to be) for one of the
strangest. Phil Pomerantz, of BuWeps, wanted me to try dimethyl
mercury, Hg(CH 3 ) 2 , as a fuel. I suggested that it might be somewhat
toxic and a bit dangerous to synthesize and handle, but he assured
me that it was (a) very easy to put together, and (b) as harmless as
mother's milk. I was dubious, but told him that I'd see what I could do.
I looked the stuff up, and discovered that, indeed, the synthesis was
easy, but that it was extremely toxic, and a long way from harmless.
As I had suffered from mercury poisoning on two previous occasions
and didn't care to take a chance on doing it again, I thought that it
would be an excellent idea to have somebody else make the compound
for me. So I phoned Rochester, and asked my contact man at Eastman
Kodak if they would make a hundred pounds of dimethyl mercury
and ship it to NARTS.
I heard a horrified gasp, and then a tightly controlled voice (I could
hear the grinding of teeth beneath the words) informed me that if
they were silly enough to synthesize that much dimethyl mercury,
they would, in the process fog every square inch of photographic
film in Rochester, and that, thank you just the same, Eastman was
not interested. The receiver came down with a crash, and I sat back
to consider the matter. An agonizing reappraisal seemed to be
indicated.
Phil wanted density. Well, dimethyl mercury was dense, all right —
d = 3.07 —but it would be burned with RFNA, and at a reasonable
mixture ratio the total propellant density would be about 2.1 or 2.2.
(The density of theacid-UDMH system is about 1.2.) That didn't seem
too impressive, and I decided to apply the reducto ad absurdum method
Why not use the densest known substance which is liquid at room temperature
— mercury itself? Just squirt it into the chamber of motor burning,
say, acid-UDMH. It would evaporate into a monoatomic gas
(with a low Cp, which would help performance), and would
go out the nozzle with the combustion products. That technique
should give Phil all the density he wanted! Charmed by the delightful
nuttiness of the idea, I reached for the calculator.
For my calculations I used the monopropellant Cavea A, not only
because it had a good density by itself (1.5) but because it would be
simpler to handle two liquids than three in the wildly improbable
event that things ever got as far as motor work. I calculated the
performance of Cavea A with various proportions of mercury —up
to six times the mass of the primary propellant. (It was easy to fit
mercury into the NQD calculation method.) As expected, the spe-
cific impulse dropped outrageously as mercury was added to the
system, but the density impulse (specific impulse X propellant density)
rose spectacularly, to peak at 50 percent above that of the neat mono-
propellant with a mercury/propellant ratio of about 4.8.
The next thing was to set up the boost velocity equation: cb =
c In (1 + <pd), and to plug in the results of the performance calcula-
tions. I did this for various values of <p* plotting the percentage
increase in boost velocity over that produced by the neat propellant
rather than propellant. The result was spectacular. With cp = 0.1,
and 27.5 percent of the tank volume filled with mercury instead of
propellant, the bulk density was 4.9 and the boost velocity was about
31 percent above that of the neat propellant; at cp = 0.2 there was a
20 percent increase with 21 volume percent of mercury. At <p = 1.0,
on the other hand, the best you could get was a 2 percent increase in
boost velocity with 5 volume percent of mercury. Obviously, a missile
with a low <p, such as an air-to-air job, was where this system belonged
— if anywhere.
I solemnly and formally wrote the whole thing up, complete with
graphs, labeled it —dead pan —the "Ultra High Density Propellant
Concept," and sent it off to the Bureau. I expected to see it bounce
back in a week, with a "Who do you think you're kidding?" letter
attached. It didn't.
Phil bought it.
He directed us, forthwith, to verify the calculations experimentally,
and NARTS, horrified, was stuck with the job of firing a mercury-
spewing motor in the middle of Morris County, New Jersey.
Firing the motor wouldn't be any problem; the problem lay in the
fact that all of the mercury vapor in the atmosphere would not be
good for the health of the (presumably) innocent inhabitants of the
county —nor for our own. So a scrubber had to be built, a long pipe-
like affair down which the motor would be fired, and fitted with water
sprays, filters, and assorted devices to condense and collect the mer-
cury in the exhaust before it could get out into the atmosphere. We
had it built and were about ready to go, when the Navy decided to
shut down —"disestablish" —NARTS, and ordered us to ship the
whole mercury setup to NOTS. With a sigh of relief, we complied,
and handed them the wet baby. Saved by the bell!
At NOTS, Dean Couch and D. G. Nyberg took over the job, and
by March 1960 had completed their experiments. They used a 250-
pound thrust RFNA-UDMH motor, and injected mercury through
a tap in the chamber wall. And the thing did work. They used up to
31 volume percent of mercury in their runs, and found that at 20
percent they got a 40 percent increase in density impulse. (I had
calculated 43.) As they were firing in the middle of the desert, they
didn't bother with the scrubber. And they didn't poison a single
rattlesnake. Technically, the system was a complete success. Prac-
tically—that was something else again.
* <p, as you may remember, is a loading factor: the propellant tank volume
divided by the dry mass (all propellants gone) of the missile.
If there are ten kilograms of dry mass per liter of tank volume, <p = 1/10, or 0.1.
against the percentage of the (fixed) tank volume filled with mercury
Chemistry is also basically math. The main problem is applying proper math and interpreting results.
The same with computers - going from task "count cats on the picture" to working program is harder than building 1 km high skyscraper. The same may happen here - doing old tasks (optimization of existing spells) will work - but I would expect that finding new ones is not going to work smoothly.
I believe his point was that, while the 'doing what they already do only way, way faster' part (i.e. spell refinement and optimization) will probably work, the 'doing what they theoretically knew how to do but had never actually tried because it required an intractable amount of work' part (i.e. spell creation) is likely to fail because of bugs in their untested algorithms.But here, Wizards already have the program. They know how to create spells through math, have known how to for a millenium, have done so for centuries (since the slide rule). The computer just allows Hermione to do it all much, much faster.
Yes, it's not a perfect simulation. There's still testing needed. But she's not trying to replace an experimental process with a simulation - all she's doing is letting the computer do the math she'd have to do by hand. And that is a task a computer can do perfectly. And thanks to that speed, she'll be able to create far more spell variants, and speed up optimization.
Dumbledore narrowed his eyes at her. "Those rituals do not just sacrifice a soul, they also demand a horrible price from the caster. That particular payment is usually delayed until they die though."
"So… no one knows what happens when we die. Where our souls go." That was a sad state of affairs, in her opinion. Such an important question, left unanswered.
I believe his point was that, while the 'doing what they already do only way, way faster' part (i.e. spell refinement and optimization) will probably work, the 'doing what they theoretically knew how to do but had never actually tried because it required an intractable amount of work' part (i.e. spell creation) is likely to fail because of bugs in their untested algorithms.
are a bit contradictory. If nobody knows what hapens after death, how can they know that those rituals extract any price at all, let alone horrible, after death?
In a way. It depends on your definition of sacrifice.I wonder if anyone is going to sacrifice themselves (or someone else) for Pansy.
Not the only way she might survive, but a dramatically-appropriate one.