How nuclear reactors work
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im not involved in anything like this but simply put in principle, u take a small particle(neutron) and shoot it at a big atom(uranium) to break it apart. The nuclease of an atom(protons and neutrons) have some “glue” holding them together. When the bug atom breaks, the glue(which has a mass) turns into pure energy(following e=mc^2). Harness the energy somehow.
Nuclear fusion generates a massive amount of heat. This heat is used to heat water and turn it into steam. The steam is then used to spin a turbine generating electricity.
That’s the simple answer anyways
For a long time, radiation was a “curiosity” with no practical application. Radioactive elements, like Uranium, emit energy, but very slowly. You could capture the energy, but you’d be there for millennia if you wanted any useful amount of energy out of it.
Then comes the discovery of the neutron. See, neutrons are different from electrons and protons in that they’re neutral – you can shoot a neutron at an atom and it won’t be deflected by the electrons or protons in the atom. The other thing about the neutron, is radioactive elements seem to emit them… AND neutrons can be used to cause a radioactive decay.
So, there are three possibilities on how we can use these neutrons.
1 – If you get a bunch of radioactive atoms together, and one atom randomly decays, which emits a bunch of neutrons, which bump into two (or any amount more than one) neighbors, which then emit a bunch of neutrons, and more atoms decay, leading to more neutrons, etc., this is a runaway nuclear reaction – a nuclear bomb!
2 – If you get a bunch of radioactive atoms together, but maybe only 1% of the atoms are radioactive. Now when an atom decays, it emits neutrons, but most of those neutrons just hit inert neighbors, and nothing happens. This is natural radioactivity, and nothing happens except a slow release of energy.
3 – If you have a properly balanced system, you can set it up so each atom releases a bunch of neutrons, but you slow them down so they only bump into one additional atom. Now the nuclear reaction is sustainable, but not uncontrolled. This is a nuclear power plant.
A typical fission reactor is a big bundle of fuel rods (radioactive materials where the actual fission takes place) and control rods (made of materials that absorb neutrons, preventing fission from taking place). When the control rods are fully inserted into the bundle, no significant fission can occur, so the reactor is shut down.
To start the reactor, the control rods are lifted partway out of the bundle. Typically this is done with a big electromagnet, so that if something goes wrong with the lifting system the electromagnet turns off, the control rods fall back into the bundle, and the reactor shuts down. This is a very common theme in reactor design: anything going wrong leads to the reactor shutting down, because that’s better than the reactor going out of control. It’s an important part of disaster prevention.
While the reaction is going, things get very hot. This heat is typically used to boil a big tank of water, which changes to steam. The steam is used to drive turbines attached to generators, which create the actual electricity. This all happens inside sealed pipes, so that the water that goes into the reactor is never released into the environment. After going into the turbine, the steam runs through chilled pipes to cool it down. Those pipes often run through a pond or lake, but again, the reactor’s water is not allowed to mix with water from the pond. Then it returns to the water tank to be boiled again.
Fuel rods of an element uranium 235 are lowered into a large tank of water along with control rods. In the tank the the uranium undergoes a sustained chain reaction which means it splits and splits and splits when it does split it creates a spark of energy or heat. This heat causes the water in the reactor to boil, when it does it creates steam, this steam turned a turbine which is connect to a dynamo that also turned and creates electricity
The goal with almost all energy sources is to spin a generator. This is essentially just a magnet rotating in a conductive coil that generates electricity through Faraday’s law. One way to achieve this rotation is using a turbine. In very simplified terms, a “reverse propeller”, which spins up as a fluid passes through it. In the case of nuclear reactors, its steam.
What steam turbine generators allow you to do is convert heat into electricity by using it to boil water. Boiling water creates steam, which expands, increases pressure, and so as it leaves the boiler it is passed through turbines and makes them spin.
Nuclear reactors boil the water with heat created through nuclear fission. The fuel rods are made of elements with very large (and thus unstable) atoms like Uranium. When one of these atom’s nucleus decays, or in other words, splits, it releases energy and neutrons. The larger the atom, the more likely it is for the neutrons it released to hit a new atom and split it, forming a chain reaction. Every time an atom splits energy is released, and a lot of this energy comes through the form of heat. That’s what boils the water to make steam to turn the turbines to produce electricity.
Nuclear reactors are at their hearts steam engines. The nuclear reaction releases energy in the form of heat, when heats the water surrounding the nuclear material. This causes some of the water to get hot enough to form steam, which is then used to spin a turbine, generating power.
Most power generators work the same way: you boil water into steam in a small space, and direct it towards a turbine. The pressurized steam moves with a lot of force, and it spins the turbine. That turbine is connected to magnets which are surrounded by coiled wires. The turbine spins the magnets, which induces current in the copper wire and produces electricity.
Where the difference exists is how the water is boiled in the first place. This process needs a lot of water, and a lot of heat. You can burn something, like coal or gas, but that produces harmful emissions.
The solution nuclear reactors provide is by boiling water using nuclear fission. Fission releases a lot of heat, and because it can be controlled using water, it makes a convenient system. You can control the fission reaction and boil the water at the same time by using the water as a coolant.
On a more technical level, this looks like a bunch of fuel rods submerged in water. Those fuel rods have a nuclear material, like Uranium, which is hit by neutrons to start a fission reaction. This reaction boils the water surrounding it, which is directed to a turbine. More water is pumped in to cool the fuel rods and prevent a meltdown (when the rods get too hot and physically melt).
The benefits of this system are environmental. Fission doesn’t produce greenhouse gasses or toxic pollutants that go into the air. The only gaseous byproduct is steam. You do need to dispose of the fuel rods safely when they are spent, but there are numeral viable solutions, and the environmental drawbacks are significantly less than fossil fuel usage.
There are safety concerns. A meltdown can result in a fire or even a steam explosion which can disperse nuclear material in the surrounding area, like what happened at Chernobyl. But these concerns are mitigated by stringent regulations.
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