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mohsenman
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Whats the problem with using water in a fast reactor. I mean moderating neutrons in a fast reactor just increases the fission chance and that is not bad is it?
If one moderates a fast reactor then it's not really a fast reactor.mohsenman said:Whats the problem with using water in a fast reactor. I mean moderating neutrons in a fast reactor just increases the fission chance and that is not bad is it?
mohsenman said:Whats the problem with using water in a fast reactor. I mean moderating neutrons in a fast reactor just increases the fission chance and that is not bad is it?
Hologram0110 said:-Higher heat capacity and high boiling point mean you don't need as much of it in the core to provide cooling
minerva said:Well, water has a really high specific heat capacity; something like liquid sodium or some other metal is actually inferior to water in terms of its heat capacity. But you need something fairly heavy as the coolant so it's not moderating the neutrons, and the liquid metals meet that requirement whilst also providing reasonably good specific heat capacity, even though the specific heat capacity would strictly speaking be inferior to water.
A fast reactor is a type of nuclear reactor that uses fast neutrons instead of thermal neutrons, allowing for the fission of heavier elements such as plutonium. This allows for more efficient use of fuel and the ability to use plutonium as a fuel source.
Moderation is important in fast reactors because it slows down the fast neutrons to a speed that makes them more efficient at causing fission. This allows for a self-sustaining chain reaction and produces more energy. Without moderation, the fast neutrons would pass through the fuel without causing fission.
Common materials used for moderation in fast reactors include heavy water (deuterium oxide), light water (ordinary water), graphite, and beryllium. Each material has different properties that affect the speed of the neutrons, allowing for control of the chain reaction.
Fast reactors have several benefits, including more efficient use of fuel, the ability to use plutonium as a fuel source, and reduced nuclear waste. They also have the potential to be used as a source of energy for thousands of years, as they can use both uranium and plutonium as fuel.
Some challenges of using fast reactors include the need for specialized materials for moderation, the potential for nuclear proliferation due to the use of plutonium, and the potential for accidents and safety concerns. There are also economic challenges, as fast reactors are currently more expensive to build and operate compared to traditional nuclear reactors.