Talk:Nuclear chain reaction

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This article lacks any citation of formulas or numbers. Also, it is extremely bias towards nuclear weapon technology instead of taking a balanced approach by discussing nuclear power, too. I am going to go through it to attempt to provide basic formulas (cited!), add nuclear power plant concepts, and make it clearer. I welcome any feedback on my edits. MNNE 05:55, 7 November 2007 (UTC)

I have finished editing the article! We still need info on fusion, though. -- MNNE (talk) 21:17, 16 November 2007 (UTC)
As I pointed out below, fusion is not a chain reaction. Man with two legs (talk) 00:00, 17 November 2007 (UTC)
I would disagree with that statement. While I am not a fusion expert, I know that the fusion reaction is propagated by the intense kinetic energy of the products of previous fusion reactions, which is the concept of a chain reaction. To quote the fusion reaction page: "When the fusion reaction is a sustained uncontrolled chain, it can result in a thermonuclear explosion, such as that generated by a hydrogen bomb. Reactions which are not self-sustaining can still release considerable energy..." Obviously, the chain reaction is not propagated by neutrons as we typically think of fission reactions, but is it not a chain reaction? MNNE (talk) 07:06, 17 November 2007 (UTC)

Seems that this article is extremely biased towards nuclear fission. What about nuclear fusion? 145.97.223.187 11:36, 6 Mar 2005 (UTC)

I agree. Is there anyone out there who can add some (cited) information on fusion? MNNE 17:47, 9 November 2007 (UTC)
Fusion is not a chain reaction so it does not belong in this article. Man with two legs 11:56, 16 November 2007 (UTC)
See above comment. MNNE (talk) 07:06, 17 November 2007 (UTC)

Needs a discussion of chain-reaction timescales, to differentiate between prompt and delayed neutrons, and so between critical and prompt critical. Linuxlad 10:11, 26 Nov 2004 (UTC)

Yes yes yes! Removed text:
The rate of reactions will accelerate exponentially if left unmoderated.
which is highly misleading at least. The role of a neutron moderator is not really control, but I can see how someone might think that.
I've just added a very brief mention of prompt-criticality to critical mass. Do we need it here too? Should we perhaps have a separate article on supercriticality, with prompt critical redirecting to it? Andrewa 02:08, 29 Nov 2004 (UTC)
Eeek! The good news is there's already an article on prompt Criticality which I've now added to category:nuclear technology. The bad news is that I've also added a disputed tag to it...! And of course the capital "C" is wrong in the title. Andrewa 02:32, 29 Nov 2004 (UTC)

The part about natural chain reactions, don't the sun and other stars count?

Sustainable fusion is not a nuclear chain rection: in this case, the reactions occur randomly inside the plasma which is exposed to extreme pressure and temperature conditions. The fusion processes release energy which indirectly induces more fusion processes by heating the plasma, but this is very different from the exponential behaviour described in the article. --Philipum 08:09, 3 August 2005 (UTC)
I added a remark about fusion.--Patrick (talk) 13:23, 17 November 2007 (UTC)

Contents

[edit] Spelling

Caesium is NOT archaic - but the standard UK spelling. Linuxlad

You are Right see Caesium Image:Gavel.gif

Scott 22:49, 13 September 2005 (UTC)

[edit] Exponential increase

Hi,

is it really a good idea to define a nuclear chain reaction (in the introductory sentence) as always having an increasing reaction rate? In a fission reactor at normal operation, the reaction rate is controlled to be constant (k = 1), but it is still a chain reaction. 217.190.37.72 15:16, 30 May 2006 (UTC)

[edit] effective neutron multiplication factor k

I don't get it. Could someone rewrite it? --Gbleem 03:14, 13 June 2006 (UTC)

[edit] Fusion is a burning process, not a chain reaction

Chain reaction requires a critical amount of fuel to start. That is why fission reactors have to contain large amount of fuel. Fusion has no critical amount, fuel can be supplied continuously. In other words, fusion is a burning process. Indeed it is simply wrong to say that fusion is a chain reaction. —Preceding unsigned comment added by 147.231.36.239 (talk) 11:32, 26 February 2008 (UTC)

However, the general definition of a chain reaction does not include a critical mass. Chain reactions occur in sub-critical masses as well (they will simply die out over time). If a fusion reaction depends on its own products (such as energy) to continue, then it still could be considered a chain reaction. MNNE (talk) 17:33, 1 March 2008 (UTC)