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Science

At My House We Call Them "Uh-Oh's" 74

Posted by Hemos from the the-little-voices-told-me-to-burn-them dept.
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."
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At My House We Call Them "Uh-Oh's" More

At My House We Call Them "Uh-Oh's"

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  • Re:From the article (Score:1)

    by Anonymous Coward
    I can't think about a library of Flames without first thinking of the great contiribution Christianity made to Civilization when they burned the Library at Alexandria.

    Offtopic, and appropiatley Flamebait-laden. Where's that "Post Anonymously" box...

  • Nate is under a carefully mandated government plan to reduce any exposure he might have to matches, candles or any other flammable unit.
  • 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

  • This might at least yield better flames in the next computer animated movie du jour :)
    --
    Join my fight against Subway's new cut!
    http://spine.cx/subway/ [spine.cx]
  • I believe the correct quote is:

    In response to !Smokey Bear character asking Ralph, "You'd never start a fire would you litle boy?"
    To which Ralph responds, "At my house we call them 'Ooopsies'!"

    This is part of an on-going joke in an earlier episode when Bart is forced to play with Ralph:
    R: "That's where I saw the leprican!"
    B: "Leprican, great...."
    R: "He told me to burn things!"

    This Roman Meal bakery thought you might want to know...

    =tkk

  • DNS (Score:1)

    by jlv ( 5619 )
    "direct numerical simulations (DNS)"

    Just what we need, another computing related meaning for that already popular TLA.
  • accidents :) hemos's house has been burned down twice i think..

    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?

  • Never mind the problems and risks of storing hydrogen as fuel

    Oh yeah, like gasoline is safe. At least with hydrogen, if your fuel tank ruptures, the hydrogen will rise & dissipate into the atmosphere, not flow along the ground looking for hot steel to ignite it or, at the very least, contaminating the groundwater.
  • This might at least yield better flames in the next computer animated movie du jour

    ..or for your next foray into USENET.

  • 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.

    -
  • Into the chamber was injected pure hydrogen, the spark ignites the hydrogen, and the hydrogen completely ignites the fuel

    How do you light this pure Hydrogen? Doesn't it need some Oxygen for combustion?
  • ...a Top Fuel Dragster :-)
  • I was more kinda egotistically thinking of the fact that a hydrogen tank rupturing is likely to explode. A rupturing gas tank may burn and unlikely explode.
  • Works with my Netscape 4.7....

  • Hydrogen Engines != Zero Emissions (Score:3)

    by Hammer ( 14284 ) on Wednesday July 18, 2001 @05:53AM (#77849) Journal
    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.

  • Explanation (Score:3)

    by CaptainSuperBoy ( 17170 ) on Wednesday July 18, 2001 @03:45AM (#77850) Homepage Journal
    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".

    --
  • 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.
  • It sure beats using massive computers to find out better ways to blow each other up [slashdot.org].
  • ... 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 [gatech.edu]
  • Move to Herndon [washingtonpost.com]? I hear he has difficulty operating candles...

  • According to this article [theonion.com], the Russians have already moved on to open-air fire tests.

  • 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.
  • Since you asked, you deserves an explanation. My parents did not abuse me. We have a great relationship and see each other several times a year (we're 300 miles apart cause of work).

    I was a terrible firebug - I played with fire a lot, and this was one time where I'd actually destroyed property. And I needed a lesson. Sure, I got a couple of 1st degree burns that day, but I had a much greater respect for fire.

  • This is called research!! (Score:5)

    by Knobby ( 71829 ) on Wednesday July 18, 2001 @04:06AM (#77860)

    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...

  • 1) Someone has to use a whole whack of energy just to make all that hydrogen

    Not to be pedantic, but hydrogen has already been made - it's just a matter of harvesting it from whatever we choose as the source. Hydrogen is the single most abundant element in the universe. Most of the planet is covered in a huge potential source of hydrogen - seawater. Harvesting hydrogen is a simple process that can be done by anyone with a battery,a test tube, and a glass of water. This is a non-issue.

    2) The Hindenburgh[sic] (Gas tanks tend to burn, pressurized gas cylinders tend to explode)

    The Hindenburg burned so quickly not because it was filled with hydrogen, but because the fabric was covered ina paint whose main components were aluminum and iron oxide. Combined, these make thermite, which burns very hot and quickly, as the oxygen is self-contained. The hydrogen actually would stop a fire in the gas bag itself, as fire needs oxygen to keep burning.

    That being said, I see no problem with using hydrogen as a fuel source, as it is highly efficient and produces pure water as the only byproduct of combustion.

  • That's the direct opposite of when I was in HS my friend josh hooked a fisher burner up to the water line rather than the gas and shot water like a major fountain. He was known as "Fireman Josh" for quite some time after that....
  • The base post said nothing of zero emission external - they just hadn't though of steam engines as external combusion before (as pointed out by the parent post to your post).
  • 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.

  • Re:hm (Score:1)

    by mazur ( 99215 )
    This dude never thought of just putting a video camera in front of the fire ?... A lot cheaper and 100% correct "fire emulation" ;)

    Wow! You make fires, that burn only in two dimensions? Please tell us how you do it, or better yet, send in an article to Nature! You're sure to win a Nobel prize.

    Stefan.

  • fires, you dolt

    *doh* I thought it was supercomputers.

    Stefan.

  • At lot of people have been doing this for years!

    In late 70s early 80s Queens University of Belfast did pioneering work on Gas flow simulation (sponsored by Yamaha -- it got them five motorcycle GP chanpionships!).

    It was a pretty slick model, trking individual molecules from carbureter to muffler in a two stroke engine. It did however take about 1 days to go through a single engine "stroke".

  • A lot more people survived the Hindenberg crash than survived the Concord crash. So I will take my chances with hydrogen.

  • From the style sheet (at http://access.ncsa.uiuc.edu/Stories/flame/js/flame .css [uiuc.edu]):

    ......

    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" : )

  • From the article (Score:5)

    by Dr_Cheeks ( 110261 ) on Wednesday July 18, 2001 @03:58AM (#77871) Homepage Journal
    From the article (pg 2):
    ....The result is a library of flames....
    But surely that's what discussion forums like Slashdot and various USENET groups are for?
  • 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

    Oh give me a break. Congress "mandating" economy standards is about as useful as legislating pi = 3.0.

    Honda was doing interesting and grounbreaking work back in the mid 1970s -- look at the CVCC engine. (Used a little charge of rich fuel/air to light the main cylinder, which was too lean to ignite conventionally. Met the California clean air standards without a catalytic converter.)

    We need more engineers who can think of stuff like that, and fewer Congresscritters bossing them around.


    --

  • Yes, people have been doing this for years. I saw this being done at Ford Motor in the early 1980s, when it took 20 minutes on a DEC-20 to model one cylinder firing. Early engine control programs were debugged against such simulations.

    The simulations get steadily better as more compute cycles become available, of course. But it was used effectively two decades ago. The big advantage is flexibility; trying slightly different valve placement in a cylinder head is easy in simulation, but a considerable job in a real engine.

  • shouldn't that be:

    &nbsp&nbspMem[x] = (Mem[x-1] + Mem[x+1] + Mem[x-xsize])/3-1;

    or something like that? Otherwise the flame would turn the entire screen white, right? (And comeon! You can average more than just three surrounding pixels with these new 486s! :)
  • 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
  • I heard it was saboteurs from Redmond.
  • This is very recent http://www.cnn.com/2001/TECH/science/07/13/hydroge n.cars.ap/index.html [cnn.com]

    People are scared of Hydrogen for no reason. Sure it burns, but it needs oxygen. Gas burns too, and it contains some of the oxygen it needs.

    The cnn article is fairly detailed and there is video. Crash tests show the Hydrogen simply dissapates in the air. The tank bursts, but there is no terrible explosion. Besides, it would be very easy to contain the force of a small pressurized tank like that.

    When your gasoline tank ruptures you have spilled gasoline everywhere. It stays there, and if it doesnt ignite the fumes can still eat your brain.

    In every way Hydrogen would be better.

    The engines are basically the same. Of course there are modifications, but they STILL are capable of running on gasoline (if you need long range)

    The artilcle states mass production of these vehicles in 10 years. I see no reason we can't make this happen in 3 years. Take the a couple of dozen billion dollars away from the fucking Missile Defense Waste and do something to make a better country instead.

    And as far as making hydrogen... any 3 year old with a battery can do it. Its a perfect task for the sun, and there are dozens of ways to create the gas.
  • You're right in the sense that simulations are only simulations. They can never replace experimental information and should be used only when experimental information is not available and even then with great care.
  • In a flame there are often no real boundary between atoms running berzerk or forming molecules. If he can figure that out on the scale of the actual flame he's really good. Then he can tune the flame so NOx and other stuff won't form.
  • at lund university [forbrf.lth.se] in sweden there is a group that is using high speed lasers to actually take pictures of the combustion process in engines. they are working with volvo to achieve the same goals talked about in the header here - reduced emmissions and increased efficiency.

    when i visited the lab there a guy explained it to me:

    1: make a mockup cylinder with a glass viewport (!!!).
    2: use a laser that emits pulses on a femtosecond time scale.
    3: shine the laser on a spinning mirror.
    4: shine the result (absorbtion image) on a very high speed digital camera.

    the result is a crystal clear picture of the fluid dynamics of the combustion process at any given microsecond. they say that this technique gives much better resolution than finite element analysis because of the incredible computational power needed to analyze the fluid dynamics in even largish (~5mm) chunks.

    it doesn't always pay to simulate what you can take pictures of...

  • And how is the steam generated? There is no such thing as "zero emissions"... you simply move the point of emission and change the pollutants.

  • hm (Score:2)

    by boaworm ( 180781 )
    This dude never thought of just putting a video camera in front of the fire ?... A lot cheaper and 100% correct "fire emulation" ;)
  • 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.

    ---

  • Back in MY days (Score:3)

    by CyberKnet ( 184349 ) <slashdot AT cyberknet DOT net> on Wednesday July 18, 2001 @08:43AM (#77884) Homepage Journal
    we didnt need supercomputers to model fire.
    We had a simple formula ... and it ran on our little 386s.

    Mem[x] = Mem[x - 1] + Mem[x + 1] + Mem[x - 320] / 3

    Them there at NASA probably ought to experiment with this!

    ---
  • That is very cool, but does not answer begging question that population is still growing, and
    amount of fossil fuels does not increase, but
    rapidly decrease. So solving that will do up only
    half of the problems related to resources and
    humanity.
  • Hydrogen is highly dangerous ONLY in case it is
    mixed with air 50/50, becomes super explosive.
    Otherwise if burned from a compressed container,
    is rather safe and clean.
  • Maybe in a hundred years or so, we'll be using computers to model...

    the wheel [cbc4kids.ca].

  • The Romans and the Muslims took their crack at buring the place down too. Not to say that what the Catholics did was ok, but they aren't the only guilty parties.
  • The compressed air engine designed by engineer Guy Nègre (CQFD Air Solution Sarl) is even better than zero emission as it consume CO2. He calls it negative pollution ! And he is selling plants to build them. Here is some info :
    english : http://www.e.volution.co.za/ [volution.co.za]. Go see it, it is worth !
    press : wired article [wired.com], very good like every wired article.
    home : http://www.mdi.lu/ [www.mdi.lu] (french).
  • *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...

  • Discovery Channel yesterday... (Score:3)

    by ffsnjb ( 238634 ) on Wednesday July 18, 2001 @04:17AM (#77891) Homepage
    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.
  • Into the chamber was injected pure hydrogen, the spark ignites the hydrogen...

    Wait a sec...How do you ignite pure hydrogen? Doesn't there need to be something there for it to react with? I mean, H2 is the lowest energy state for pure hydrogen, isn't it?

  • <Offtopic>
    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 [nytimes.com] by more than a gallon, well, all the research in the world isn't gonna help :(

  • Misleading Topic (Score:4)

    by jmcneill ( 256391 ) on Wednesday July 18, 2001 @03:59AM (#77894) Homepage
    For a second I was sure that this article was about ICQ...
  • Well, both piston and turbine steam engines come to mind. Sterling engines too, (though they never have been used for much).
  • how long is it going to take the military to jump on this to make bigger, more explosive weapons?
    Are you quite sure that the big weapon manufacturers are not doing this already?
    My guess (well, no need to guess, really) is that they are already doing this. If there is anybody with good funding, it has to be the weapon manufacturers.

    on the other hand, wouldn't it bee cool if the big drug cartells tried to develop a new pipe, that burns all the weed you want in a perfect way... ;)
  • to super saturate the gas flow with air

    I'm genuinely ignorant and curious about this:is the gas ssaturated with the air or is the air ssaturated with the gas? I figured it wouldn't make a difference if it were just saturation, but super saturation?

  • 2) The Hindenburgh (Gas tanks tend to burn, pressurized gas cylinders tend to explode)

    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. [ucla.edu]

    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 [qub.ac.uk].

  • Probably not... (Score:3)

    by kaszeta ( 322161 ) <rich@kaszeta.org> on Wednesday July 18, 2001 @04:28AM (#77899) Homepage

    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."

  • You Go Now! (Score:5)

    by Kowgod ( 323669 ) on Wednesday July 18, 2001 @08:02AM (#77900) Homepage Journal
    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 [snpp.com], 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?
  • This reminds me of the Backdraft ride at Universal Studios. I guess the special fx guys came up with all sorts of ways to get flames to burn and dance on cue. And without the use of a super computer.
  • I say it was communists! or republicans :P but ah, that does kind of suck. on the bright side (light bulbs, right, get it? lol) maybe it won't um, happen again?
  • You're forgetting only 2 things...

    1) Someone has to use a whole whack of energy just to make all that hydrogen

    2) The Hindenburgh (Gas tanks tend to burn, pressurized gas cylinders tend to explode)
  • 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 [h2engines.com] at the h2engines website.
  • Well less polution is a great thing but think about the price difference between a regular engine and one of these puppies! I think it will be a while before they catch on.
    ---
  • That's what happens when you spill gasoline on a hot engine.


  • Anyone else notice that the rings of flame are not unlike the rings of plasma they're using for facilitating fusion [slashdot.org]?

    Other parallels between fire and nuclear power:
    • Both will destroy if uncontrolled
    • Both leave harmful waste
    • Research is being done on both to find ways to use them without waste (This article, and fusion)
    • Both used as weapons in their infancy
    • etc, etc, etc

    I'm sure more can be thought of. Interesting to think about, though.
  • On the Discover channel, several years ago [96, 97?], on the program Discover 2000, they were showing a research group that had changed the way gas was ignited in the cylinders of a combustion engine. Instead of using a spark plug directly, they used a spark plug on a small chamber directly above the cylinder. Into the chamber was injected pure hydrogen, the spark ignites the hydrogen, and the hydrogen completely ignites the fuel. They demonstrated their system with slow mo photography of a combustion cylinder [with one side covered with some type of high impact/high thermal tolerance plastic] the difference between regular directly sparked combustion, and combustion with hydrogen. The difference in the way the fuel ignited was remarkable. Emmissions dropped to below measurability by the emmissions test equipment used by states with emmission laws, and the needle didn't even move. Everything that came out was CO2 and water. As for the safety of hydrogen, I would like to point out that most people's gas tanks, that are partially filled with gas and air, are already massive bombs, so what's the big deal about sticking a tank of hydrogen under the hood? The fuel efficiency was amazing. The performance of the engine was also suitably enhanced. Imagine a Ford Pinto going 180 mph down the freeway! -DogNo7

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