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At My House We Call Them "Uh-Oh's"
Kowgod writes "For those of you who have never checked out the NCSA's Access Magazine, this issue's cover story will hopefully spark your interest. It seems an aerospace engineer, Cyrus K. Madnia, over at the State University of New York at Buffalo is trying to use super-computers to model fire. By tinkering with the mechanics and components of a flame he hopes to discover ways to burn fuel more efficiently, thus emitting less pollution. Kind of an odd twist on the quest for the zero emission internal combustion engine."
Nate is under a carefully mandated government plan to reduce any exposure he might have to matches, candles or any other flammable unit.
Yeah, I'm that guy.
What in the Hell kind of Commie pinko tree-huggin' left-leaning homo unamerican liberal comment is that?
What else were computers meant for?
Misfit
Was the above moderated as flamebait as some sort of "fire" joke? Have the moderator guidelines been changed to encourage using moderation as some sort of stealth posting method?
I see even classic Slashdot is now pretty much unusable on dial up anymore.
What he's doing is removing all the fans from the supercomputers, which quickly causes them to generate a very realistic model of fire.
And remember, if you build a man a fire, he'll be warm for a day; but if you set a man on fire, he'll be warm for a lifetime.
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IC-engines will produce emisions, always. In the ideal case there will be no harmful emissions (i.e. only water.)
An IC-engine that burns hydrogen with air will produce at least nitrous oxides (nitrogen burnt under high temperatures.) assuming absolutely no pollutants in the air... If there is hydro-carbons or other combustible pollutants in the air, well who knows what fun emissions comes out of the zero-emissions engine.
Never mind the problems and risks of storing hydrogen as fuel in your car.
I am however cautiously optimistic to the prospect of safe and clean fuel-cell engines.
For those of you who might not get the joke, Ralph Wiggum of the Simpsons says "At my house we call them uh-oh's".
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On hydrogen safety... it is a myth that hydrogen is 'highly dangerous' in pure form. This is largely due to the Hindenberg airship accident, which was blamed on it's hydrogen.
It turns out, years later, that the hydrogen was NOT the culprit in the Hindenberg; the real culprit was the new coating used on the canvas covering... it was essentially rocket fuel (they did not know this at the time).
You are correct; hydrogen fuel is no more dangerous than gasoline fumes.. or propane, or anything else.
And if you obtain prime air to fuel mixtures, for say, propane.... you'll find it does a great deal more damage.
... I was modeling combustion during my undergrad years as far back as '93, and there were already several labs across the country doing computational combustion work. For a variety of reasons computational combustion is one of the hardest simulation fields you can tackle. Here's a plug to the leading lab of my old prof, the Computational Combustion Laboratory at Georgia Tech
Move to Herndon? I hear he has difficulty operating candles...
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If so, we're doomed.
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when I was 13, I tried to determine whether a series of matches burn hotter when grouped in a square or circular formation. I caught the living room rug on fire. Then I had to find out (because my dad was curious) how many matches were in a typical book. The kick was, that I had to burn each one down to my fingers before dropping it.
Hey guys! There are a lot of people throughout the world trying to model combustion with the goal of improved efficiency.. Madnia at SUNY UB is pretty good (a little close-minded) but he's not the only guy out there this sort of work...
For those who haven't read much about CFD (Computational Fluid Dynamics) here's a little overview.. DNS (Direct Numerical Simulation) solves the equations of motion for a flow to obtain information for all the scales (wavenumber information).. The problems with DNS include restrictions on Reynolds number, limited run time (very few statistically independent samples), and domain size. I believe that currently the largest DNS that has been performed was on a 1024^3 element grid.. Unfortunately, it still really isn't fine enough to deal with a Reynolds number beyond a few hundred (many practical flows have Re #'s ~1e6+).. To model higher Reynolds number flows many researchers have moved to LES (Large Eddy Simulation) type approaches, where the equations are solved directly for scales above a certain range, and the subgrid scales are handled using a variety of models. LES has a handful of problems too.. The big problem when using LES for combustion work is that a large percentage of the mixing that these researchers need to manipulate in order to improve their efficiency occurs in the subgrid scales that they're modelling...
Try sandwiching a thin layer of fuel and oxygen between two pieces of pyrex and igniting. That's a good way to study 2d fires. However, in 2d there's a lot less phase space for turbulence, and hence there are qualitative difference between 2d and 3d fires.
color: #F9EBB4;
That renders as a light brown-yellow sort of colour. Perhaps your browser just doesn't like style-sheets. BTW, I think the wraparound in this comment box has stuck an unwanted space in that URL - you'll have to remove it.
Awwwww; I was hoping that at least 1 person would moderate me as "Flamebait" : )
Goodness! I guess university professors have finally progressed to the level of early 90's demo groups. The next headline will be "Bob R. Dobbs of the University of Texas discovers unified theory with help of Future Crew"
-- Simply Frabjous!
nath
This dude never thought of just putting a video camera in front of the fire ?... A lot cheaper and 100% correct "fire emulation" ;)
Probable impossibilities are to be preferred to improbable possibilities.
Aristotele
new fangled do-whatsits.
I dont know what sort of modeling you do, but in my line of scientific work we do HRA (High Resolution Analyzing - 320x200 in 256 colors). You cant do scientific work without detail; cutting the width of the DFM (Dynamic Fire Model) removes too much of this.
Quite frankly, I heard there were issues with the floating point on those 486s, so I will only trust my 386 + FPU. Besides, DARPA and NASA wont spring the cash for a new box, just for extra research time.
BTW, regarding your hypothesis about averaging pixels... please remember that I *do* hold the patent on the DFM technique, as well as any dirivatives. So if you get it into your head to compete with me, you better watch out. Any attempts to reverse engineer the final flame will be prosecuted under the DMCA.
Incidently, I find adding in more pixels just increases the error rate, since the average is an FLOAT, and has to be typecast to an INT due to limitations of the new VGA standard.
Sincerely,
Scott Blomfield, BSA.
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Video meliora proboque deteriora sequor - Ovidius
we didnt need supercomputers to model fire. ... and it ran on our little 386s.
We had a simple formula
Mem[x] = Mem[x - 1] + Mem[x + 1] + Mem[x - 320] / 3
Them there at NASA probably ought to experiment with this!
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Video meliora proboque deteriora sequor - Ovidius
the wheel .
Donate background CPU time to fight cancer.
*sigh*
Ralph: This is my swing set. This is my sandbox. I'm not allowed to go in the deep end. That's where I saw the leprechaun!
Bart: Right, a leprechaun.
Ralph: He told me to burn things.
Bart: Uh huh...
They had a segment on the Michael Holigan show (not nearly as cool as Hometime, but that was a rerun on TLC...) where some research institute was developing natural gas burners that burned 20x cleaner than traditional natural gas burners. They use a convection current to super saturate the gas flow with air, burning less fuel in the process for the same output. Even better was the fact that you can hold onto the burner without getting burned because the current pushes the flame away from the burner itself. Try that with a Bunsen burner.
"Why do you consent to live in ignorance and fear?" - Bad Religion
Boy does THAT bring back memories! NCSA v1.x on an HP-UX v9.x system using good old Mosaic. I bet if you asked 100 Apache admins what NCSA was at least 50% would give you a blank look!
</Offtopic>
This is a pretty cool idea. I can imagine modelling a candle flame is hard enough. Trying to model all the forces and flows inside a combustion cylinder must be mind boggling! Who knows - maybe there is a 'next generation' combustion engine that will allow for better emissions till fuel cells and the like are usable for prime time. Of course if Congress won't get off their butts and actually raise fuel efficiency standards by more than a gallon, well, all the research in the world isn't gonna help :(
Top Most Bizarre/Disturbing Error Messages
For a second I was sure that this article was about ICQ...
How are you wrong? Let me count the ways:
1) The Hindenburg did not burn because it was full of hydrogen. It would have burned had it been filled with helium. Some guy at NASA proved it.
2) Gas tanks do not tend to burn. There are hundreds of thousands (if not millions) of them not burning all over the world right now. You probably have several hundred very near you as you read this (in automobiles, in lawnmowers, etc.).
3) Pressurized gas cylinders do not tend to explode. There are hundreds of thousands (if not millions) of them not exploding all over the world right now. You probably have several dozen very near you as you read this (fire extinguishers, propane tanks, medical oxygen tanks, helium tanks to blow up [inflate] children's ballons, etc.).
4) The Hindenburg was not a gas tank, nor was it a pressurized gas cylinder.
5) Nothing about the Hindenburg has anything to do with the idea of using hydrogen as a fuel. The Hindenburg ran on kerosene. Saying the Hindenburg "proves" hydrogen is dangerous is like saying the Kursk "proves" nuclear power is dangerous since it was a nuclear sub (or that Three Mile Island "proves" that electricity is dangerous since that's what it was making).
And as for your first point about all the energy used to "make" the hydrogen, you miss the point entirely. There are dozens of ways we can (and do) make hydrogen, some better than others. There is only one way to make gasoline. At least hydrogen will give us some options, one of which is make it from gasoline as needed.
If all this should have a reason, we would be the last to know.
I doubt it, since special effects types and directors always seem to favor things that look "cool" over anything realistic. And the rest of the realism goes the wayside due to concerns about "drama" and filming requirments.
Good examples of this include 2-D "shock waves" in space explosions (heck, Lucas went to the trouble of adding these unrealistic effects into the Special Edition of Star Wars) and sound effects in a vacuum.
I can easily envision a director throwing out someones new, accurately-calculated flames because they don't look "firey enough."
Whaaa? Man, how can someone screw up such a classic line!?
FIRST of all, its not Smokey the Bear, its Hosey the Bear.
And second, as you can clearly read here, the line truly is:
Hosey: You're not going to start any fires, are you?
Ralph: At my house, we call them, "uh-ohs."
Why oh why don't they avoid this by teaching Simpsons in school?
-- Mesmer is the Dairy King Remove your panties to email me.
Why work with fire, when hydrogen provides a solution for zero-emissions internal combustion engines?
An Associated Press report states:
DEARBORN, Mich. (AP) -- Ford Motor Co. is working on a hydrogen-powered internal combustion engine that it says could be a cleaner-burning alternative to the gasoline motor until automakers perfect a fuel-cell powertrain.
It's a modified version of Ford's 2-liter Zetec four-cylinder gasoline engine that promises 25 percent to 30 percent better fuel efficiency, Bill Bates, Ford's manager of alternative power sources, said Monday.
The company plans to begin road-testing later this year.
Read more here at the h2engines website.