Nuclear reactor startup (with sound)

A nuclear reactor, formerly known as an atomic pile, is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nuclear fission is passed to a working fluid (water or gas), which in turn runs through steam turbines. These either drive a ship's propellers or turn electrical generators' shafts. Nuclear generated steam in principle can be used for industrial process heat or for district heating. Some reactors are used to produce isotopes for medical and industrial use, or for production of weapons-grade plutonium. As of early 2019, the lAEA reports there are 454 nuclear power reactors and 226 nuclear research reactors in operation around the world.
#Uranium
#Reactor
#Nuclear
#Startup
#NuclearReactor
#HowitsDone
#nuclearReactorstartup

[thisisgarbage]

One of the rare instances where something is actually as cool as it is in the movies

[xrayninerbravo]

Something to note is that the reactor here is the TRIGA reactor (short for Training, Research, Isotopes, General Atomics) is only a research reactor. Actual commercial reactors are more confined and are much more powerful than the one shown here. This reactor does not make electricity at all.

[onman]

This feels like it's straight out of a science fiction film! I truly love what humanity's brightest minds can accomplish by joining efforts.

[giorgiocatone]

Cherenkov radiation is one of the most beautiful colors in the spectrum

[miitoob]

What you don't want to hear from your nuke plant operator: "Whoa!"

[burritomensch]

Fun fact: That blue glow, or Cherenkov radiation, happens when charged particles get shot out of the reaction and through the water keeping the reactor cool faster than the light around them.
Basically, light travels a bit slower through water, so the reaction shooting electrons off at light speed is obviously gonna leave a bit of a wave behind. That energy has to go somewhere, so the water particles get "excited" and emit photons.
What you're seeing is a sonic boom, except the light barrier is being broken.

[dadjake]

That glow is magical - no wonder movies depict it like that all the time. I wish I could visit a research reactor myself at some point, I'd love to see that.

[keithdmaust]

In the early seventies I assembled and welded the handling tool that raises and lowers the control rods. Myself and my fitter fabricated them on an amazing table about 100 ft long and flat within a few thousands of an inch. Once it was all assembled we hoisted it up vertically to test it it was a fun job and as a young machinist and welder I learned a lot.

[jamessnook]

To expound on my comment from before: Uranium produces 2.4 average neutrons per fission. The problem is that these neutrons have high energy, in the Mega electron volt range. In order to cause a cascade of another fission the neutrons need to slow down to about 0.4 electron volts to be absorbed by another uranium atom. To do this they have to bounce off other material in the reactor core many times, like hundreds or thousands of collisions to lose enough energy. If the material in the core is hot already - it doesn't lose as much energy per collision so it requires more collisions. This extra heat effectively reduces the reactivity of the reactor. Normally the water surrounding the core is used as the moderator, but there are limits to how much energy the water can absorb and dissipate over a short period of time. In these clips there is a prompt injection of reactivity which is not how reactors normally increase their power level, it is closer to how an atomic bomb works. What makes it able to do this is the special fuel used in TRIGA reactors. It is Uranium with a Zirconium Hydride lattice added in. During the prompt injection of reactivity (when the operator shoots out the center control rod) - the hydride heats up faster than the surrounding water can, making the fuel essentially un-reactive in the process. So as the core becomes super-supercritical - the heat itself causes the reactor to become un-reactive and the power level drops to sub-critical. I have pulsed a reactor like this many times - the original Mark I TRIGA in San Diego. We typically injected ~ 60 cents worth ( one cent is supercritical) of extra reactivity and I think the most we injected was just under $6 worth, which felt like an earthquake for a few seconds.

[DD_]

For anyone wondering this reactor does not generate electricity and is used to test different isotopes for safety in other reactors, and the rippling is water they put it into water because it’s cooled and absorbs radioactive particles before they reach the surface while cooling the reactor, very basic and simple reactor unlike actual ones which require more cooling and heating.

[jamessnook]

The commenter below is correct - these are TRIGA reactors. The flash comes from the prompt supercriticality produced from ejecting the center control rod out of the core pneumatically, which also makes the pop sound . The reactor would be taken just critical using the manual control rods and then the center rod would get shot out. As the temperature rose - the zirconium Hydride lattice in the fuel rods would poison the reaction by inhibiting the thermalization of the neutrons and the reactor would come back down to subcritical in less than a second. At the reactor where I worked, during some experiments, we would inject enough reactivity to make the building shake. Even with 20ft of water covering the core - a big pulse would set off the klaxon (it was set to trigger at 5 Rad)

[philiphatfield]

"There is nothing you can do to stop it, Mr. Bond".

[Dave_Isla]

Understanding the intricacies of nuclear reactor startup isn't just about appreciating complex terminology; it's about recognizing the remarkable blend of science, engineering, and meticulous control required to harness the immense power of nuclear energy safely and efficiently. Each term used in describing the process sheds light on the precision and expertise involved, from manipulating neutron flux to orchestrating the choreography of control rods. Explaining these concepts not only deepens our appreciation for the scientific endeavor but also underscores the critical importance of responsible stewardship in utilizing nuclear technology for the betterment of society.

[apl]

"and all of a sudden I had a strong metallic taste in my mouth...."

[MMoreau]

Blue light is produced by the Cherenkov effect, quite impressive when you see it for the first time ...

[wrcnnbz]

I see why Godzillas atomic breath is blue ☄️

[paradox]

Hell yeah brother we need more commercial nuclear plants. Here's hoping for fusion, too!

[Bobcat]

In 1980 I was at a 1256 MW reactor cooling pool in outage mode. As the nuclear fission slows, the glow of the water dims. It is a color you would never forget. I think they were waiting on a safer radioactive level, so a diver could enter. Nuclear fission is achieved slowly to control the fission, not like flipping a light switch. Chernobyl is a result of hurried reactions and hasty decisions. Most commercial reactors operate until their fuel is spent and they are placed in outage mode for fuel replacement. If a shutdown occurs, it takes a long time for the reacted fuel to stabilize. The startup would be slow and I don’t believe you would hear all the noise. Most tests are performed on computers or simulators to make sure we don’t have a Chernobyl.

[NelsonClick]

For those who don't understand nuclear power (myself included) this is an intensely serious job. No mistakes. Ever. How would you like a job where failure is not an option?

[marcuscarana]

So that's the blue flash they saw from the demon core.