The nuclear-engineering tag has no wiki summary.
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Containement system of a nuclear reactor: role of the water moderator
In a modern nuclear reactor for example a PWR there are multiple containment systems which prevent the release of radioactive material into the environment and shield the environment from the ...
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4answers
690 views
What is the minimum amount of fissile mass required to acheive criticality?
Wikipedia gives the following definition for critical mass.
A critical mass is the smallest amount of fissile material needed for a sustained nuclear chain reaction.
No mention is made of a ...
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Approximately how much would a LFTR cost? [closed]
Would anyone happen to know how a LFTR costs?
Please could you include the efficiency and payback time.
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2answers
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How would a black hole power plant work?
A black hole power plant (BHPP) is something I'll define here as a machine that uses a black hole to convert mass into energy for useful work. As such, it constitutes the 3rd kind of matter-energy ...
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1answer
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Speed of neutrons in a nuclear reactor
How fast (in $\frac{\mathrm{m}}{\mathrm{s}}$) are typical neutrons before and after slowing down in a nuclear reactor (with U-235 and $H_2O$ as moderator)? Do you have any reference for the values?
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Why not assimilate nuclear waste into “igneous” rock?
I was reading a question about why not to drop nuclear waste into volcanoes; the short answer is it would come back out and not be rendered safe.
Ignoring the cost and energy requirements, why can't ...
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1answer
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How is it possible to calculate the energy liberated by a given fission process?
How is it possible to calculate the energy liberated by a given fission process? For example, in the fission of a $^{235}$U induced by capturing a neutron?
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Light water moderated reactors vs Liquid fluoride thorium reactors [closed]
I have read a lot about Liquid Fluoride Thorium Teactors (LFTRs) and their advantages over Light Water moderated uranium Reactors (LWRs).
I don't care too much about problems of safety, nuclear ...
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1answer
55 views
Why is the total interaction cross section larger for incident particles with lower energy?
The cross section of a nuclear interaction is a measurement of the probability of that interaction occuring. These probabilities are typically presented in terms of barns ($10^{-28}$ m$^2$) as a ...
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2answers
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Nuclear based wireless power?
I would like to ask if there is any Nuclear process which can be used to produce a wireless power ?
Is there any nuclear process can be radiate to the environment with no harm to human beings?
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2answers
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Military-grade U-235 uses
In the news it is often mentioned that some countries are going to enrich uranium to "military grade" (i.e. 80%+) and that it is possible to use it for a nuclear bomb.
1) Is that correct that there ...
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What is this underground nuke test name and params? [closed]
Here is a famous video of an underground nuclear test:
http://www.youtube.com/watch?v=S1f6vbiuUt0
What are its characteristics?
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1answer
527 views
Why did the Hydrogen in Fukushima explode *outside* the reactor vessel?
As pointed out before, it orginated inside the reactor vessel but exploded outside: how did it get there? Did it pass the shell by diffusion or was it released by the engineers?
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Water-cooled fast neutron reactors
Can anyone explain why fast neutron reactor designs use sodium/lead/salt cooling, instead of water (heavy/light)?
Is that because neutron absorption by water would not allow to break even in fuel ...
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neutron transport approximations for nuclear rocket modelling
I'm pretty ignorant regarding neutron and nuclear transport modelling, but i'm interested in trying to pursue it for a particular pet project. It regards modelling of nuclear reactions like those ...
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1answer
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What do we do with the byproducts of Nuclear Fusion? [closed]
http://wiki.answers.com/Q/What_are_the_byproducts_of_nuclear_fusion
So I quickly googled the byproducts of fusion and got the above link.
It looks to me that you'll be left with He atoms. So what ...
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1answer
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Nuclear Salt Water Rockets: viability and follow-up
This is the original paper by R. Zubrin proposing the Nuclear Salt Water Rocket design.
Basically the design is that a capillar set of pipes store a uranium salt-water solution, inside a cadmium ...
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1answer
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What causes the structure visible in first few milliseconds of a nuclear explosion?
Following on from this question, here is a high-speed photograph of a nuclear explosion, taken about 1 ms after detonation: (source) As anna v pointed out, several similar images can be seen in a ...
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Why don't modern spacecraft use nuclear power?
The Voyager 1 & 2 spacecraft launched in 1977 with Plutonium as their source of electricity. 34 years later they claim these two spacecraft have enough power to last them until at least 2020. That ...
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5answers
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Thorium radioactivty vs Uranium radioactivty nuclear power
May i please open this question by asking that if you intended to answer this please could you provide links based on your answer. I have read ( and posted one ) on thorium and a lot of the answers ...
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What practical issues remain for the adoption of Thorium reactors?
From what I've read on thorium reactors, there's enormous benefit to them. Their fuel is abundant enough to power human civilization for centuries, their fission products are relatively short-lived, ...
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4answers
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Why can't there be a trap door under nuclear reactors in case of meltdown?
This may be a naive question, but after the Fukushima Daiichi partial meltdown and studying the aftermath of Chernobyl it seems they could be helped by this idea.
In Chernobyl, the liquidators that ...
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0answers
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Properties of spilled spent nuclear fuel pellets
Can someone please explain to me the physics of a pile of spilled nuclear fuel pellets on the floor of a spent fuel pool? Specifically, what can we expect in terms of heat and radioactivity releases, ...
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1answer
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Direct nuclear reaction in nuclear physics
Time taken to occur a direct nuclear reaction is very low $10^{-22}$sec . I want to know the Importance of direct nuclear reactions.
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1answer
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Why are we not using thorium for energy? [duplicate]
Possible Duplicate:
What practical issues remain for the adoption of Thorium reactors?
I have been reading and watching a bit on thorium TH 90 and cannot understand why this is not being ...
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2answers
110 views
How to detect radiation on the metal (coin)?
I've got metal coin : http://www.worldpeacecoin.org/
Ruble/dollar, a coin of disarmament with certificate. But, I am very spleeny person, I fear of it's radiance level and I don't know if I can trust ...
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1answer
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The synthesis of $^{254}\text{No}$
How is $^{254}\text{No}$ synthesised?
Could you explain the reaction where it is preceded by $^{208}\text{Pb}(^{48}\text{Ca}, 2\text{n})$?
References to articles are well enough—I was somehow unable ...
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1answer
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Is there a good summary of all nuclear fusion approaches?
I am pretty sure, that during last 60 years of well-funded research a lot of ideas on nuclear fusion were already tried and ruled out.
Is there some summary describing all of them and why they ...
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3answers
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Nuclear physics problem, Why do we use high weight atomic elements?
So as far as I know, nuclear fission uses high weight atomic elements to manufacture power. If the risk of runaway reactions are a major reason for not expanding this technology, why don't we use ...
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2answers
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Statistical Weighting Factor on thermal neutron importance
The problem is concerning the use of a thermal fluxed squared weighting factor in a thermal reactor.
I have seen in sources the thermal flux in a reactor is squared as a statistical weighting factor, ...
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4answers
208 views
Which part of making an atomic bomb is the hard part and how many people know how to do that? [closed]
I mean which part of the process of making an Atomic bomb is the hard and how many people know how to do that on Earth. Is it in hundreds or less i.e. 20 - 50 people or even less?
Don't get me wrong ...
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3answers
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why aren't there nuclear powered aircraft?
I know this might sound like more of an engineering question that about physics, and it probably is, but bear with me: i'm still not sure if the answer to my question lies in the physics or in the ...
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1answer
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How does the curiosity rover get it's power? [duplicate]
Possible Duplicate:
Mars Curiosity Power System
I found a web page that said it uses Plutonium. I am sure it's not based on fusion or fission. What is the basic idea on which the power ...
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scaling laws for density and temperature of high-energy explosions
I'm wondering if there are heuristic ways to derive how the peak density and temperature of nuclear explosions scale with the amount of fissile/fusible material.
Does it matter what the explosion ...
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1answer
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Nuclear fuel pellets - when does the chain reaction start?
Questions about nuclear fuel:
Does nuclear chain reaction start in fuel pellets even before they being installed in reactor? If not, why not? My understanding is that since the fuel pellets are ...
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Is there a sound theoretical argument against inner-shell induced nuclear chain reactions?
There is a claim often made about cold fusion, that it is excluded theoretically. The main theoretical argument is that electronic energies are too low to overcome the Coulomb barrier, since d-d ...
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2answers
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critical density to create macroscopic nuggets of nuclear matter
Is there a critical size that an hydrogen bomb detonation needs to have in order to produce neutron-degenerated matter?
Does anyone knows if matter in this state would be stable at ambient ...
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2answers
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Nuclear reactor control rods
What is the relation between control rods surface exposed into a nuclear reactor and neutron energy? Is it linear? I mean, how do neutron absorbing rate change with the progressive immersion of ...
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Why does nuclear fuel not form a critical mass in the course of a meltdown?
A BWR reactor core may contain up to 146 tons of uranium. Why does it not form a critical mass when molten? Are there any estimates of the critical mass of the resulting zirconium alloy, steel, ...
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1answer
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Boiling water reactor
What are the typical power densities in conventional boiling water nuclear reactor per cubic centimeter of fission material?
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Can a nuclear reactor meltdown be contained with molten lead?
If lead can absorb or block radiation, would it be possible to pump molten lead into a reactor core which is melting, so that it would eventually cool and contain the radiation?
Is there something ...
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Russian Doll Teller Ulam?
Can you trigger a thermonuclear explosion from a smaller thermonuclear explosion in a scaling way, so that starting from a small laser ignited fusion within a small fissile container, using the X-rays ...
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4answers
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Why was PACER abandoned?
The PACER project is described in this question: How much of the energy from 1 megaton H Bomb explosion could we capture to do useful work?
Why was it abandoned? It seems that it is the only readily ...
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2answers
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If there is a meltdown at the Fukushima reactors, would the control rods melt also?
According to the reports, the shutdown procedures at all the Fukushima reactors were successful, and all the control rods were fully inserted.
So - if there was a meltdown, would the control rods ...
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Is the E-cat for real?
Does this thing really do what they say?
http://www.youtube.com/watch?v=EhvD4KuAEmo
If it does, it looks like this will probably be the biggest breaktrough in science ever :)
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Fukushima Nuclear Plant Running? [closed]
If there had been no tsunami would the Japanese Fukushima nuclear plants be operating today?
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Is it viable to convert nuclear waste into safe isotopes?
I read that powerful pulsed lasers can change isotopes:
J. Magill, et. al.: "Laser transmutation of iodine-129".
Did anyone estimate what would be the energy costs to transmutate 1 kg of fission ...
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0answers
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How viable is reuse of nuclear waste at this point, and what are future prospects? [closed]
I keep seeing documentaries describing the pile-up of nuclear waste from nuclear power stations in the US and in other countries. Countries such as Finland are working to deposit waste in old mines in ...
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2answers
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Is a Rubbia thorium reactor safer than other modern reactor types?
I keep wondering how a Rubbia thorium reactor would handle a natural disaster of Fukushima level intensity. As I understand it the nuclear chain reaction would stop instantly if the power is cut, but ...
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2answers
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How much radiation exposure in the US was caused by the 105 nuke tests in the Pacific?
Between 1947 and 1962 the US conducted 105 tests of nuclear weapons in the "Pacific Proving Grounds". I'm wondering how much radiation exposure resulted on the west coast of the US. These were part of ...
