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Atomic Power Plant Mechanisms
Power can work for you or against you.
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Training as applied to the SAGE system might be used to train operators of atomic power plants, using the plant facilities to conduct simulated machine operations. Considering atomic power plant hazards, however, it makes more sense to build a separate training simulator, possibly using the central control panel of the power plant.
The panel would be hooked into a computer that portrayed its reactors, and representative operational data would be used in the equations. The data would have to be consistent with the natural processes of the plant. The result would be the analog to a flight simulator.
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The principle of an atomic power plant is straight-forward and essentially the same as for a conventional power plant -- one that burns fossil fuels, namely coal, oil, or gas. The purpose of the plant is to produce electrical power. For this you need to drive a generator, typically by supplying steam to the rotary blades of a turbine.
In an atomic power plant, the fuel is an isotope of uranium and the furnace is a reactor. To "burn" the fuel in the reactor, you bombard it with neutrons, which are the neutral particles of an atom's nucleus. The bombardment "splits" many of the heavy uranium atoms into smaller but, unfortunately, very radioactive particles. The fissure also releases a great deal of energy and still more neutrons, which collide with more atoms of the fuel to extend the fission process.
If you have enough uranium, and you slam the atoms with a controlled supply of the neutrons, you can produce enough fissures to release just the desired number of other neutrons and create a chain reaction, or a continuous flow of heat.
The operative word, here, is 'controlled,' for you can have too little or too much heat. If you have too few atomic interactions, you don't generate enough heat and the process dies away. But if you have too many fissures, you cause the reaction to accelerate, which can create too much heat and the danger of a meltdown, with catastrophic consequences.
The correct number gives what is known as critical mass. This is the state in which, on average, one neutron arising from a fissure produces just one further fissure, and no more. Maintaining the critical mass is the heart of the control problem.
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You control the neutron reaction by using appropriate amounts of neutron absorbing material, like cadmium, like embedding cadmium rods among the uranium fuel rods and moving them in relation to the uranium to adjust their effective lengths. The variation increases or decreases the rate of absorption of neutrons. The greater the effective length of the rods, the more neutrons they absorb; the shorter they are, the less they absorb.
You also have to draw the heat from the reactor to boil the water and provide steam for the generator. One way is to use two separate water-flow systems (called primary and secondary water supplies).
In the primary system, water is pumped under high pressure through the fuel rods. Because the water is under high pressure, it doesn't convert to steam but stays liquid and reaches very high temperatures. This system serves two purposes. One, to moderate the speed of the neutrons to control the rate of fission, and two, to absorb heat produced by the fission.
Since the water in the primary system passes over the fuel rods, it not only becomes very hot, but also becomes highly radioactive. For this reason it isn't used directly to drive the generator; otherwise, the contamination would spread. Instead, it is pumped to a heat exchanger, where it gives up heat to the secondary water supply but doesn't contaminate it. Now, the secondary system itself is not under high pressure, so the water in it boils normally and converts to steam. It is this steam that is fed to the turbines.
To provide the desired training, it would be necessary to simulate this entire control process, including the actions taken by the operators. So equations have to be prepared for each step.
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