A fact from Deuterium fusion appeared on Wikipedia's
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This is an interesting article.
The sentence "Deuterium burning prevents this by acting as a thermostat that stops the central temperature rising above about one million degrees, which is not hot enough for hydrogen burning" is obviously vital, but its is not entirely clear to me. Does this mean that excess heat above one million degrees is absorbed by the conversion of deuterium to helium? Is this like a phase change where adding heat energy to ice at the melting point will, for some period, cause melting without causing a further temperature rise? The fact that deuterium "burning" prevents a rise in temperature makes it sound as if the reaction is endothermic, but that doesn't seem right. Can this sentence be clarified? μηδείς ( talk) 20:08, 10 July 2010 (UTC)
The reason why Hydrogen Fusion requires the temperature of 10^7K is because the protons repel. But deuterium has essentially the same charge, so it shouldn't be easier to fuse, at a temperature of 10^6K. On top of that, the neutron in deuterium adds extra mass, which means more inertia, which makes it harder to accelerate. So why does deuterium fuse so easily? And finally, if it is so seemingly easy to accelerate the deuterium(the other requisite is still a proton, so it doesn't matter), why don't stars fuse 2 deuterium atoms and make helium-4? 32ieww ( talk) 23:34, 28 January 2017 (UTC)
I want to know that how much energy is released from 1 kg of duterium(fusion) as compared to 1 kg of coal . Siwan2002 ( talk) 11:27, 24 December 2019 (UTC)
Since D+D is the major reaction used in testing tokamaks including JET and ITER, I think it deserves a mention here... if not its own article.
It's not as easy as D+T of course, but it doesn't produce the high-energy neutron that is one of the main obstacles to use of D+T. Which sounded pretty good at one stage.
The problem with this is that there's a side reaction in which D+D produces Tritium. I'm not sure whether this was even predicted or its consequences appreciated before the D+D tests began at JET, but it was quickly demonstrated there when their supposedly pure Deuterium fuel began producing high-energy neutrons from D+T fusion!
Sad conclusion: No point in hoping that fusing pure Deuterium will avoid irradiating the PFM with these nasty high-energy neutrons, and thus avoid the need of expensive remote handling equipment to deal with the highly radioactive waste. Oh well, back to D+T.
I'm sure this can be sourced but don't have the sources to hand. Andrewa ( talk) 17:06, 11 December 2020 (UTC)
Why is deuterium the most easily fused isotope available to protostars? Shouldn't it be tritium since it's got an extra neutron and occours naturally? Tritium's the most easily fused isotope on Earth. 2603:6000:8740:54B1:C941:7ADA:D88:9366 ( talk) 16:34, 6 May 2023 (UTC)
A fact from Deuterium fusion appeared on Wikipedia's
Main Page in the
Did you know column on 13 July 2010 (
check views). The text of the entry was as follows:
|
This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||
|
This is an interesting article.
The sentence "Deuterium burning prevents this by acting as a thermostat that stops the central temperature rising above about one million degrees, which is not hot enough for hydrogen burning" is obviously vital, but its is not entirely clear to me. Does this mean that excess heat above one million degrees is absorbed by the conversion of deuterium to helium? Is this like a phase change where adding heat energy to ice at the melting point will, for some period, cause melting without causing a further temperature rise? The fact that deuterium "burning" prevents a rise in temperature makes it sound as if the reaction is endothermic, but that doesn't seem right. Can this sentence be clarified? μηδείς ( talk) 20:08, 10 July 2010 (UTC)
The reason why Hydrogen Fusion requires the temperature of 10^7K is because the protons repel. But deuterium has essentially the same charge, so it shouldn't be easier to fuse, at a temperature of 10^6K. On top of that, the neutron in deuterium adds extra mass, which means more inertia, which makes it harder to accelerate. So why does deuterium fuse so easily? And finally, if it is so seemingly easy to accelerate the deuterium(the other requisite is still a proton, so it doesn't matter), why don't stars fuse 2 deuterium atoms and make helium-4? 32ieww ( talk) 23:34, 28 January 2017 (UTC)
I want to know that how much energy is released from 1 kg of duterium(fusion) as compared to 1 kg of coal . Siwan2002 ( talk) 11:27, 24 December 2019 (UTC)
Since D+D is the major reaction used in testing tokamaks including JET and ITER, I think it deserves a mention here... if not its own article.
It's not as easy as D+T of course, but it doesn't produce the high-energy neutron that is one of the main obstacles to use of D+T. Which sounded pretty good at one stage.
The problem with this is that there's a side reaction in which D+D produces Tritium. I'm not sure whether this was even predicted or its consequences appreciated before the D+D tests began at JET, but it was quickly demonstrated there when their supposedly pure Deuterium fuel began producing high-energy neutrons from D+T fusion!
Sad conclusion: No point in hoping that fusing pure Deuterium will avoid irradiating the PFM with these nasty high-energy neutrons, and thus avoid the need of expensive remote handling equipment to deal with the highly radioactive waste. Oh well, back to D+T.
I'm sure this can be sourced but don't have the sources to hand. Andrewa ( talk) 17:06, 11 December 2020 (UTC)
Why is deuterium the most easily fused isotope available to protostars? Shouldn't it be tritium since it's got an extra neutron and occours naturally? Tritium's the most easily fused isotope on Earth. 2603:6000:8740:54B1:C941:7ADA:D88:9366 ( talk) 16:34, 6 May 2023 (UTC)