Talk:Flame

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[edit] General

Vandalism suspected under the temperature and color section. Last paragraph, toward the end, the sentences seem to be unrelated to the topic. —Preceding unsigned comment added by 169.232.121.111 (talk) 09:16, 12 February 2008 (UTC)

Commented out a section on other oxidisers this should really be in fire. I might move the flame article away a little from fire and discuss other instances of flames. This should help it become less of a sub-section of the fire article. I cleaned up the introduction it was a little misleading. Wolfmankurd 08:54, 14 May 2006 (UTC)

This page is a train wreck, I'm going to spend a few minutes and try and clean it up. RobertDahlstrom 04:13, 19 November 2005 (UTC)

Ok I cleaned it up. Got rid of the gallery, thumbnailed the big flame picture, did a bunch of grammatical edits of the flame color section, added a small see also section, and added a bit of wikification.

After doing these edits I think this section doesnt really have much information and I think it should be merged into Fire and have a redirect created appropriately. Theres never really a fire where there isn't a flame, or vise versa. Or at least i've never heard of any exception so if someone has any further information please let me know before I choose to merge it. Thanks RobertDahlstrom 04:48, 19 November 2005 (UTC)

I seem to remember something about fire that you can't see (and thus no flame).

I also know that often flames are very HARD to see...


anyway i think the merge is a good idea -- if you dont do it soon i will. TastemyHouse Breathe, Breathe in the air 09:18, 16 December 2005 (UTC)

Well, I'd disagree in saying theres parts of fire that you can't see, given the definition given on Fire's page: Fire is a form of combustion. Linguistically, the word fire refers to the combination of the brilliant glow and large amount of heat released during a rapid, self-sustaining burning of combustible fuel.

Brilliant i'd say implies not only visible, but clearly visible.

Anyways I think i'll carry out the merge pretty soon. RobertDahlstrom 07:37, 18 December 2005 (UTC)

[edit] Temperature/Color?

The section on temperature and color is, to the best of my understanding, all wrong. The oranges and yellows associated with hydrocarbon flames from candles, wood, and movie explosions are the result of blackbody radiation from soot and steam, and so follow that relationship between color and temperature. However, the blue flame found in soot-free flames result from electrons jumping among energy states in either oxygen or carbon dioxide (I forget which). Also the listed flame temperatures don't correspond to the adiabadic flame temperature of hydrocarbons, which is very similar for almost all hydrocarbon fuels. —BenFrantzDale 20:11, 23 January 2006 (UTC)

Right, and if I hadn't just copy edited but turned on my brain for just a second I'd have noticed it myself. Blue flame would translate to a temperature >10000K. Not very likely. I propose we chuck whole article, merge with fire, and do a redirect. I'll throw out the rubbish about the temperature now. --Dschwen 21:32, 23 January 2006 (UTC)
The illumination generated by a flame is not "blackbody" radiation. Blackbody radiation assumes a state of thermal equilibrium which will not exist in the immediate context of highly exothermic reactions.Hetware 01:50, 21 August 2007 (UTC)

Before you throw the baby out with the bathwater, a lot of it IS correct. The only part that is wrong about the temperature is the last bit where the extrapolation down to blue is made; the upper part of the article correctly states that the blue is not blackbody radiation but emission from molecular species (probably C2 and CH in fact). The red-orange-yellow colour part of the statement in dispute is correct. Yogibear63 22:09, 28 January 2006 (UTC) Anyway I have now taken a shot at correcting it Yogibear63 20:08, 29 January 2006 (UTC)

Then of course, you're all being biased to normal gravity conditions. Check out http://science.nasa.gov/headlines/y2000/ast12may_1.htm. "On Earth, gravity-driven buoyant convection causes a candle flame to be teardrop-shaped and carries soot to the flame's tip, making it yellow. In microgravity, where convective flows are absent, the flame is spherical, soot-free, and blue." Elle vécut heureuse à jamais (Be eudaimonic!) 02:23, 13 February 2006 (UTC)

No, what Yogibear63 is saying is in exact agreement with that NASA reference. The yellow candle flame in gravity is produced by blackbody radiation from the soot whereas the blue flame in microgravity is Emission spectrum from the gasses. --72.244.218.235 05:16, 4 August 2006 (UTC)

There appears to be at least two sources of intense blue light arising from the combustion of hydrocarbons. Both originate, as stated above, from electronic transitions and appear differently in the flame. In atmospheric-pressure flames one takes the form of a thin cone that is generally rather localised (in the case of a candle) just above the wick. The second is a deeper blue emission that is much more extensive but not as intense and often masked by the near-black-body emission of small soot particles. The light-blue emission arises from the spontaneously-emitted photons when CH radicals, in their electronically-excited "A" state, return to their ground electronic state. CH(A) -> CH(X) + light. The corresponding wavelength of the photon emitted is 431 nm. The electronically-excited CH radicals are produced by two chemical reactions, both involving the C2H radical; (1) C2H + O2 = CH(A) + CO2 and (2) C2H + O = CH(A) + CO. Their relative importance depends on the ratio of atomic oxygen to molecular oxygen and also on the local temperature. Note that the concentration of CH(A) produced by this mechanism is greatly above its concentration that could be produced by collisional excitation alone and it is therefore not in thermal equilibrium with its surroundings. As such, the emission intensity cannot yield information on the flame temperature by assuming a black-body in this spectral region. The more extensive deeper-blue light is probably caused by an electronic transition of CO or CO2, but the (chemical) source of these electronically-excited molecules is still a subject of investigation.

[edit] Plasma?

Can I just ask something here..? Is flame always plasma? I thought only certain types of flame from high temperature combustion is plasma such as arc welders and lightening - these are ionised gas flames, I'm not sure ordinary fire is.Dholt 16:34, 22 March 2006 (UTC)davidh

I think flame is by definition not plasma. While the nomenclature "plasma flame" is probably used around things like a plasma cutter (since the plasma does look very much like a flame). But strictly speaking, I think a "flame" is a the site of a chemical reaction and I think (although I am not a chemist) that most plasmas are all free atoms and electrons; if there can be no molecules, there can be no chemical reactions (right?). —Ben FrantzDale 22:22, 22 March 2006 (UTC)
Flame is a plasma. It is an ionised gas. Srnec 20:03, 8 April 2006 (UTC)
It's a plasma, but not plasma. It is a form of plasma, but not plasma itself, not like a lightning bolt. --Anyr
It's actually only the boundary region of what is called the flame that is a form of plasma. Most of what is called flame is a gaseous mixture of fuel (and oxidant when premixing). Coucilonscienceorg 21:34, 26 April 2006 (UTC)
It's not plasma at all. it is superheated carbon. in a hygrogen burner, there is no flame because there is no carbon Andrew Hampe--72.169.155.10 22:40, 2 May 2006 (UTC)

Fire is one of the natural forms of plasma. Zyrm 02:06, 12 May 2006 (UTC)

My belief was a plasma was like a gas with ions and electrons flowing freely, or nearly, and so a portion of a flame was a plasma. Wolfmankurd 20:48, 13 May 2006 (UTC)

Yes, that's true. The definition of a plasma is particles, charged or neutral, that flows freely. That makes the beginning of this article not true, since generally a low temperature flame is NOT a plasma all through. Check out the article on Plasma (physics) --rhevin 22:24, 26 May 2006 (UTC)
Hmmmmm, but the main body of the flame, the actual coloured area, is atoms coming out of a plasma state and electrons returing to thier lower energy states with black body radiation giving the glow. The requirment for it to be a plasma is only that a portion of the atoms to be ionised, as in that article. Also, a definition of plasma can also be a conducting gas which a flame is. Wolfmankurd 20:20, 28 May 2006 (UTC)

I find it misleading, though, to write "flame is a plasma", especially in the first sentence, because being made up in part of ionized gas is not the defining attribute of a flame. As noted above, the glow of a flame has nothing to do with ions. Actually all gas is (to a very small extent, of course) partially ionized.. Why not just discuss the plasma thing further down in the article?

The flame is a plasma, the glow aroung the flame isnt, but the actual body is a plasma. Only part of the gas needs to be ionised for it to be a plasma, I'm trying to re-write this but am having a hard time finding a consensus, Wolfmankurd 18:47, 30 May 2006 (UTC)

My point is, while being a plasma is a characteristic of flames, it doesn't define them. I think if somebody found a combustion reaction which produced this glowing "tongue" of gas, but which happened to not be significantly ionized, we'd still call it a flame... Don't object to the word "plasma", just don't think it's so important. --213.47.116.40 23:12, 18 June 2006 (UTC)

[edit] Quality

Have any of the most recent edits of substance been for the better? I would revert them, but this seems to be a controversial and misunderstood topic. Srnec 20:04, 8 April 2006 (UTC)

The misunderstanding, form my point of view, stems from if it should be considering flame from fires and others as a sub section or flames more generally.Wolfmankurd 21:05, 28 May 2006 (UTC)

[edit] Flame temperature

A candle is definitely NOT 1,400 Celsius. It is 1,400 Fahrenheit at most.

I agree with that statement, it definitely isn't 1,400 Celsius, if it were...well then there would be no more candles, or just really really hot candles. --Anyr 19:17, 26 April 2006 (UTC)


http://hypertextbook.com/facts/1999/JaneFishler.shtml I found this. But I still find it hard to believe. Wolfmankurd 20:56, 13 May 2006 (UTC)

If you think about the mass of gas/particles and the energy transfer it's not too hard to believe. A very small amount of "stuff" does not require a great deal of energy to become very hot and thus can't deliver a great deal of energy to anything else. Plus, the energy is quite rapidly dissipated by the surrounding gas and carried away by convection. --213.47.116.40 17:54, 28 May 2006 (UTC)

The problem with measuring flame temperatures is the loss of heat to the surroundings. The ADIABATIC temperature for a candle flame IS 1,400 degrees C. This means that in an ideal environment where absolutely no heat is lost, a candle would reach that temperature. However, ideal is far from reality, thus a candle can't heat objects to 1,400 C (It would melt metals like copper, gold etc.). Main source: http://www.doctorfire.com/flametmp.html

[edit] Merge (Flame with Fire)

Considering the presence of an enormous number of people who think that the Sun is a ball of fire, and considering that there is an enormous number of people who have not experiemented with a candle to determine what a flame is, I am in favor of keeping the flame article as an introduction and adjunct to combustion.

The concept of fire is loaded with many extraneous topics that are culturally determined and are not necessarily related to combustion with an air oxidizer.

This article is small and extremely valuable in educating people. If it is moved to fire, it will be lost and the people who would benefit from it might never see it. A simple solution would be to explain that in the article, as well as have flame redirect to fire.Hezzy 20:39, 30 April 2006 (UTC) keep seperate — A flame is just a component of a fire. The article "flame" should discuss things such as the chemical reactions involved and properties of flames, whereas "fire" should be an overview of all the different aspects relating to fire. Ae-a 15:41, 13 May 2006 (UTC)

I agree. There is a lot of basic concepts in flame that would be lost in a fire and that are important.
The fact that you dont think there is a difference between flame and fire is why they are being kept seperate. you can have a flame but no fire( e.g. the sun) and a fire but no flame( e.g. when you burn paper and there isnt a flame but it glows and it burns oyu get me...) :) --Wolfmankurd 20:51, 13 May 2006 (UTC)

those might be good points however the simple answer is that there are basically 2 articles about the same thing, flame is only the singular of fire If you are concerned that it will get lost in such a big article stick that up at the top as an introduction and further explain fire in the rest of the article. 02:03, 12 May 2006 (UTC) Although I find this article quite incomplete and rather poor in quality (for example, aside from the inaccurate description of flame color and definition as a plasma, the inclusion of nuclear fusion is a bit of a stretch), I believe there should be a distinction between a flame and fire (flame is certainly NOT "only the singular of fire"), as the former lends itself to a more detailed technical description. At present, the article adds little to that on fire, but that could and should be changed. Just a comment from a reader. --213.47.116.40 17:27, 28 May 2006 (UTC)

  • keep seperate I agree with Ae-a|Ae-a. They should be kept separate, because a flame is a component of fire. Aero Flame 21:54, 11 February 2007 (UTC)
  • keep seperate is my vote. Rracecarr 22:54, 11 February 2007 (UTC)
  • keep seperate I also agree with Ae-a. When you think of 'flame' different things come to mind than when you think of fire. They should be kept seperate. Neglekt 17:57, 21 February 2007 (UTC)

Concensus: KEEP SEPERATE --Daysleeper47 21:10, 5 March 2007 (UTC)

separate, retards! -lysdexia 05:51, 4 October 2007 (UTC) —Preceding unsigned comment added by 68.123.4.253 (talk)

[edit] Recent edits

I have made many changes and additions to the article and thus removed the previous warnings and cleanup notices. What do you think of the current state of the page?--Deglr6328 01:41, 11 September 2006 (UTC)

It looks nice, thank you :)

[edit] LOL

Does anyone know where to get a chart of flame colors in regards to what squarerootof3 element is burning? Need it for a science project, thanks!!

There's one at Flame test. In the future, you'll probably get a better response for these kinds of questions at the Science reference desk. Dave6 09:47, 15 January 2007 (UTC)


[edit] General

If somone is looking up fire the more likley be looking up things like forest fires how to start fires for constructive purposes so on and so forth. If somone looks up flame they are probly more intrested in chemistry and the properties of flame

i apologies for any poor spelling i wrote this in a hurry aslo this is my frist time commiting to a wiki entery other then deleating some rubbish people put on a wiki stub —The preceding unsigned comment was added by 85.210.59.126 (talk) 21:21, 17 February 2007 (UTC).

[edit] microgravity

I don't modify it myself because english is definitly not my first language. The article say "In microgravity or zero gravity, such as an outer space environment(...)". In outer space the gravity does exists. If an object have no relative speed relatively to the sun, be sure that it will fall pretty fast. Zero gravity occur mostly in a circular orbit, when the resulting acceleration is null. --Madlozoz 18:58, 8 August 2007 (UTC)

[edit] Coolest flames

The article talks about the temperatures of some hot flames, but what is the coolest flame you can get? --RLent (talk) 17:09, 16 January 2008 (UTC)