I love these threads.
JW Science Quote Of The Day 8-27
by TD 14 Replies latest jw friends
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done4good
Yes, they can blow up. All one has to remember is Chernobyl. If the containment building leaks, there is a lot of high-pressure radioactive gases (like water vapor) just waiting to be released into the atmosphere.
Yes, but basically what TD said above is accurate. Also keep in mind that Soviet reactors had no containment building. One of the worst things the US has done in recent history, (ok, it was 1979), was fall victum to "The China Syndrome" and give up its nuclear power program.
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Open mind
Hi TD,
Nice to see you posting. 4 years of reading TD's posts might get me close to a college education.
Open Mind
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Disillusioned JW
Though you are correct in saying that thermonuclear is not the proper word to use for fission nuclear reactors, nonetheless fission nuclear reactors do generate enormous amounts of thermal energy (heat). That heat is then used to turn liquid water into steam to operate turbine electric generators which in turn generate electricity.
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TD
Diogenesister (From another thread)
TD what is a control rod please? And what does the acronym SCRAM stand for?
Reactor control rods act as a sort of throttle in the sense that they moderate the reaction. Here's an easy way to visualize what's happening using Uranium 235 as an example:
A neutron (Small grey circle on the left) strikes a U-235 atom causing it change into U-236 momentarily and then split into two smaller atoms. (Barium and Krypton in this example.) These smaller atoms require a lot less energy to hold them together, so the excess energy is released as heat. The split also releases two or more extra neutrons, which may strike other U-235 atoms resulting in more heat and more neutrons. This doubling is called neutron multiplication and it can quickly get out of control.
In commercial reactors, the control rod mechanism is a bundle of about 20 rods composed of materials which absorb these extra neutrons, which prevents them from traveling into adjacent fuel pellets and rods. This in turn lessens the thermal output of the reactor.
In English, a SCRAM is an emergency shutdown of a reactor. The control rods are completely inserted and water based solutions laced with the same sort of materials as the control rods themselves are injected into the reactor coolant.
There isn't any real agreement today over the etymology of the word. In the very early days of nuclear research, scientists would experiment on table tops (I kid you not) and if something went wrong, the best thing to do was to run, which is one possible explanation for the term. Other explanations are possible acronyms the word could have stood for, like Safety Control Rod Activation Mechanism, but again, there's no real consensus on this.