On Nov 4, 2009, at 11:19 AM, Abd ul-Rahman Lomax wrote:
At 12:27 PM 11/4/2009, Horace Heffner wrote:
On Nov 4, 2009, at 4:52 AM, Abd ul-Rahman Lomax wrote:
To the extent that anyone is taking this seriously, there are some
students laughing so hard they are in danger of something falling
off.
Means nothing of course! There are plenty of students and professors
laughing at the lunatics that think it is possible to create fusion
in a jar. They haven't done the work, and they know nothing of the
field. What else would one expect?
The purpose of this list is to explore these things with an open
mind. That is not to say explore without serious factually or
logically based criticism, but explore without ridicule, derision or
ad hominem attacks.
If it makes the peanut gallery laugh, all the better. The world
needs more humor! And, it needs more creative problem solving.
What's happening here, though, is exploration of an idea that is
then extended into realms not even remotely covered in the
announcement. I approached it with an open mind. And what I found
was signs that this was a jape.
You didn't explore the web site.
Not like cold fusion at all. Pons and Fleischmann reported excess
heat and neutrons. From that report, there was either a world-class
expert in calorimetry being really, really stupid, or there was an
actual anomaly. Just from the press conference. Sure, he was wrong
about the neutrons, but he didn't make some really bogus claims
about the explanation, the most he did was suggest it was deuterium
fusion, which was probably an error. He provided no theory.
These people are providing a theory! That seems blatantly a spoof,
to me, a transparent trick that might fool someone for a few
minutes, unless the person has no understanding of physics.
The theory looks wrong, but that's irrelevant. All CF theory leaves
lot to be desired. This doesn't mean it is not useful to design
experiments, and it doesn't have anything at all to do with whether
the data gathered is valid. Data trumps theory.
All the stuff about exerting a force on the vacuum, stated here, is
to explain an experimental effect, but without any description of
the experiment.
Uh, that was *my* comment. I think their theory, which is not based
on that, is probably wrong, as I said earlier.
What's going on? The video doesn't explain *at all*.
You ned to read the web site.
They make it look like this experimental apparatus is floating.
Okay, was it floating under it's own power; that would be 1 g
acceleration.
You have to be kidding. It is an air pad equivalent of a torsion
pendulum. Torsion pendulums are a standard approach to looking for
*small* reactionless thrust. The thrust being measured peaked at
257 mN. If a device produces thrust through continued 360 degree
rotation it rules out most ambient field interaction, unless there is
some form of commutation feasible.
The test was far from ideal and could have been much improved by
driving it with battery power. However, they did reverse thrust
directions, so that eliminates torque bias concerns for the bearing,
unless something stupid was done.
The thing was a little wobbly, it looked like. A little wobble, and
it would shoot off to the side! Anything keeping it from wobbling?
Nothing that I saw and nothing described. They don't say what is
going on at all, except that it's a demonstration. Demonstration of
what? How much power consumed? Why is this a fixed camera view? Why
not look at this from all different angles?
Wobbles don't matter much. A lot of stuff I've put on torsion
pendulums wobbled plenty. Didn't affect at all fact I could
determine they had no net thrust! 8^)
I gave you the URL:
http://www.emdrive.com/
If you had explored it you would have found some answers.
Feasibility Study:
http://emdrive.com/feasibilitystudy.html
"The design factor, calculated from as-built measurements of the
thruster geometry was 0.497. An unloaded Q of 5,900 was measured. The
maximum thrust, measured using a precision balance was 16mN for an
input power of 850W, which is very close to the thrust of 16.6mN
predicted from equation 1."
Demonstration Engine:
http://emdrive.com/demonstratorengine.html
"The engine was built with a design factor of 0.844 and has a
measured Q of 45,000 for an overall diameter of 280 mm. The microwave
source is a water cooled magnetron with a variable output power up to
a maximum of 1.2 kW."
"To obtain the predicted thrust the engine must maintain stable
resonance at this high Q value. Major design challenges have included
thermal compensation, tuning control and source matching."
"The engine was tested in a large static test rig employing a
calibrated composite balance to measure thrust in 3 directions, up,
down and horizontal. A total of 134 test runs were carried out over
the full performance envelope, with a maximum specific thrust of
214mN/kW being measured."
Dynamic Test (of the demonstrator engine in the Video)
http://emdrive.com/dynamictests.html
Flight Program:
"A Flight thruster development programme has started, with delivery
of the first thruster scheduled for August 2009. This thruster is
specified to produce a static thrust of 85mN for a 3.9Ghz input of
300W. The thruster mass is 2.9kg. A minimum operational lifetime of
15 years is specified. The envelope dimensions are shown below."
And of course the FAQ answers a lot of questions:
http://emdrive.com/faq.html
I think the answer is obvious. They wanted to see how easy it was
to get people stumbling over themselves to refute or speculate.
Occam's Razor.
Looks to me like they *might* have stumbled over something that works
for reasons they don't really understand.
Nothing wrong with speculating about vacuum forces, though, I'm
sure, most here are aware of the problems. This thing would have to
be operating on the vacuum inside, i.e., the empty space, what used
to be called the "ether," for this to mean anything. And then, is
it ejecting the ether in one direction? (There is your reaction
mass -- and what effects would this have on Other Stuff.) Or is the
ether like a stiff mat? We'd have to think of it as rigid and
immovable. It's a mess.
Well, I could try to explain it from my point of view, but I might
find myself spilling some beans I don't want to spill, so I'll just
let it drop.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
