+Moris Doehmann Day be called Cherenkov Radiation. You see The electrons are moving faster than light thru a medium causing a shock wave.(NOT FASTER THAN C OR PHOTONIC VELOCITY IN A VACUME AS NOTHING IS FASTER THAN C)
My two cents, in this particular case, I don't think he was really being a grammar Nazi. As a self-admitted grammar Nazi who happens to know many, and be the offspring of, engineers, they do tend to suck at spelling. I saw my dad spell Jurassic "Jurasek" one time. I LOL'd!
"If this continues to get interest I would be happy to make more videos of the reactor and radiation in general. I enjoy teaching people and changing minds about nuclear power and other technologies." Yes, please do that, and explain it in the vid!
Beautiful vantage point on the core, and I love how the GoPro camera sensor picks up some occasional direct radiation signals (sparkles), particularly at 1 MW.
Amazing to see that. It is just like a giant kettle. You can even spot the control rods being raised and lowered to control the output. Many thanks for sharing.
Thanks for adding some time stamps. I didn't really expect many people to watch this video, just needed to get the raw footage up for some people to see. Maybe I will actually edit a video with this footage...
We got to see this reactor being fired up in 1992 with our advanced physics class trip. It was the neatest thing, and I still tell people about it. We got to see the wd-40 thread test film and had access to the neutron howitzer to do particle counts. A lot of people are surprised when I tell them there is a nuclear reactor right in State College. That's a cool job you have there.
Magnificent. it's so beautiful to see how power of atom tamed in such simple and elegant form. Triumph of human mind, but still so much left to achive.
Holy crap I was not expecting that blue glow! Would I seriously be able to see that with my naked eye!? It looks so incredible it seems fake, really amazing stuff!
Starting at around 7:00, you can see some white flashes, especially as they close in on a portion of the shot. Tiny little one or two pixel sized white flashes. Those are from the radiation hitting the cmos chip right?
The blue glow is due to the charged particles traveling faster then the phase velocity of light in that particular liquid. You can actually see the huge amount of particles glowing as they are escaping into the surrounding liquid. Awesome.
For those who don't believe this is real, whenever radiation hits a camera you see specs of white because it damages the material inside it, since this is a high quality gopro, the outter shelling blocks alpha and beta radiation, when you see the specs this would be gamma radiation, hence the large amount of water.
I worked with reactors in the US Navy, went through training on a submarine prototype that started out in shipyard and made it to another major overhaul in shipyard on an aircraft carrier. Even then, I did not see this level of detail and beauty of a fission reaction. Thanks for the rare treat to see this. BTW, I see some lines that go down towards the core in between the control rods, what are the purpose of those? Also, are you limited to short runs or is there a way to reject heat that I cannot see here?
I was also in the nuclear Navy, submarines though. The other tubes going down to the reactor are tubes that we can drop experiments down in to, and also some conduit going to temperature detectors in the core. We can run for long periods of time. There is a cooling system for the pool (not shown). If running at full power, the pool reaches an equilibrium temperature of about 26C.
็Thanks for the footage! Please do take more videos like this. Very educational. Such a rare opportunity to get to see how this thing works. I'd been spending time reading all the top comments and your clarification.
Way, way cool!. I got a tour about 30 years ago when I was student. Only thing missing is a video of a prompt critical event. I was told it looked like a flashbulb going off at the bottom of the pool. Well done on the video, and THANK YOU to the folks who allowed you to post it on TH-cam.
There are a few things happening. Above 200kW, nucleate boiling begins to occur on the cladding of the fuel rods. The bubbles from nucleate boiling don't last long. After they break away from the cladding they collapse in the bulk of the fluid channels. This is good for heat transfer. Many of the bubbles are from the dissociation of water. In the high neutron flux, water is split in to hydrogen and oxygen. Any sort of radioactive isotopes contained in the bubbles either decay or are low level and well under NRC limits.
Concentrations are very low. We also have to be running exhaust fans in the reactor bay any time the reactor os operating. If there is a problem with the exhaust system while the reactor os operating, it will automatically shut down. Because of the small size and low risk, our reactor is not in a containment like a commercial reactor. We have 'confinement,' meaning that the air through the reactor bay is controlled (and kept at a negative pressure) but it is far from air tight. In the event of a high radiation condition, the normal exhaust is automatically shut down and all air leaving the reactor bay goes through a sophisticated filtering system.
Actually seeing the Cherenkov radiation glow is amazing. I have never seen a picture of it much less a video. It's like something out of a Science fiction story but real life.
Thanks for posting this. It's fascinating to see a reactor actually operating. Now just to do some research on the differences between your research reactor, the one at NC State University, and the one just up the road from me (Shearon Harris). Thanks again!
I was a reactor operator in the US Navy. This video is probably one of the best videos I have ever seen showing Cherenkov radiation. Really, really awesome video! By the way, I assume this is some test facility somewhere? I have no idea of any facility where you could drop a camera into a pool and film a reactor going critical to 1MW, particularly with it not being in a pressure vessel. This is just freaking awesome!
I was also a Navy reactor operator. This is the research reactor on the Penn State main campus. It's just used as a large neutron source for research and commercial testing.
just been reading your reactions to comments, you get my subscription just for being a nice, interesting guy. p.s if you do more of these videos, annotation or a voice over of the stages would be interesting. I'm interested but really i don't know what i'm looking at here
That Cherenkov radiations is just...beautiful. Absolutely stunning. One of the best videos out there hands down. Only one question - how the hell camera survived the gamma radiation this little beast must output? Or I'm missing something. Also, how do you handle camera afterwards? I would imagine it could have bits of radioactive decay on it and everything.
The good thing about gamma radiation is that it doesn't make things radioactive like neutron radiation. The camera can handle a lot of gamma radiation before it fails. I would think that the light sensor would fail if exposed to very high gamma flux, but that would really take a lot.
Right, thanks! I thought gamma will still leave things radioactive after exposure. So, there's no neutron radiation of any kind in this particular reactor? You'd have to fuse or break up elements violently for that to occur I'd imagine.
When gamma rays hit camera sensors, they create bright specs or streaks (depending on the angle compared to the sensor). Look in the darker areas, like the left, and you can see them while it's running. You can watch the gamma exposure happen in real time.
Bogdan Sdr not scary! Just a natural phenomenon called Cherenkov radiation. Essentially EM radiation from electrons moving faster than light through the water. In water light moves about 75% the speed it does in a vacuum (space).
Bogdan Sdr that blue is visible to the naked eye. It's actually pretty rare to be able to see it in person. At commercial power plants the reactor is in a vessel and it can only be seen during refueling. This reactor is pretty unique
Cherenkov radiation. Electrons from decay moving faster than light through water. I always thought it made a beautiful blue colour. Edited with the correct explanation from Alex below. and yes this is a unique reactor! thank you for sharing this.
Wow this is fantastic footage. If you notice the random white pixels of light that pop on and off are accentually stray electrons hitting the CCD of the camera and causing an overload on the sensor.
Alex is figuring it's a gamma ray from N16 wandering near the camera and then shedding. But I'm thinking the odds of a gamma ray hitting the sensor are low, whereas an electron has a pretty good chance of being intercepted by the sensor, I'm thinking almost 1 to 1. And flipping the bit to a maximum all white is exactly what we would expect an electron to do. Would a gamma ray even trip that photonic sensor? If it did, that means a molecule spilled electrons and got damaged, didn't it? Is there damage now to the sensor? Spots maybe? I like electrons a lot better.
The blue Cherenkov Radiation is beautiful. It never gets boring thinking that small cube radiates 1MW of power. Think ~500 kettles boiling at once. (2 kilowatt each)
ANNOTATED VERSION OF THIS VIDEO IS NOW AVAILABLE!! Be amazed by the beauty of nuclear power and learn something new at the same time! I hope you enjoy the new video! (the sound is fixed in the new video also!) th-cam.com/video/uYrhWO_ZLYw/w-d-xo.html
A charged particle is required to create Cherenkov Radiation, so a photon itself cannot cause the glow. However, photons from fission can undergo photoelectric effect with electrons in the water and get them moving faster then light through water. A charged particle is required because there needs to be a magnetic field created. Moving charged particles create a magnetic field, but it usually dissipates quickly back to a neutral state. When the charged particle moves faster than light through water, the magnetic field is created faster than it can return to a neutral state (speed of light) creating a sort of 'pressure' wave of a magnetic field (in sonic boom terms). That phenomenon is what causes the emission of the blue photon that we can see. Its the neutralizing of that compressed EM field.
It would be more accurate to say that it tries to go faster than light, but before it can get there, the extra energy is spilled, in the form of more light.
Heat can be measured in either British Thermal Units, Watts, calories, etc. In physics, it is usually watts, since that is a cleaner measure of power to do math with, and all power is heat. (Unless they feel like using joules)
Alex, thank you for showing this, and for all the explanations. Highly educational! Although science and technology are (and need to be) purely rational things, there are always moments of amazement... Once had the opportunity to stand next to the spent fuel pit of a commercial nuclear power plant and will never forget the blue glow of the Cherenkov radiation I saw down there. Please keep up your outstanding contributions, and best wishes for your career!
Thanks for the clear answers. 1) I didn't know you can have moderator mixed with the fuel. Neat. Sounds like it moves in a self regulating direction. As it heats up the neutrons, it's automatically reducing the neutron cross section. Pretty slick. 2) WOW. Deliberate power excursions. Exciting stuff. I looked up your "prompt critical". Spectacular video there! I see the pipes(?) jumping. Do the high power excursions make noise? 3) Understood. 5) I was just wondering what the control system looks at to know where to position the control rods moment-to-moment. . I think you've really answered what it is, it's the neutron flux since you've explained that the power output can be accurately known using just the neutron flux. I'm happy to see universities with such nice facilities. Thanks again for sharing.
1) It is very unique to this design of reactor. It's needed because we have the ability to pulse, like you saw in the other video. The negative reactivity feedback in a commercial reactor due to changing of moderator density is a delayed effect. The ZrH response to an up power is more immediate. 2) The pipes you see moving are the control rods. The power excursion doesnt cause any noise directly. We cause the power excursion by pneumatically 'shooting out' a control rod to a specified height. That air is what you heard. We have 4 control rods. 3 are held up by electromagnet and the other is held up by air pressure. To pulse, we go critical on the 3 electromagnetic rods. We then drive a stopper out to a specified point for the air driven rod. When we initiate the pulse in the control system, 85 psi of air is placed under a piston which shoots the rod up against the stopper. The pulse happens very quickly. The control system scrams all of the rods within 5 seconds of initiating the pulse. That is the second round of noise you hear (air being vented to atmosphere). And you see the control rods drop in to the core (they look like pipes). 5) Correct. The neutron detectors on the back of the core are the primary indication of power. The control system adjusts rod heights based on a few things, but mainly the current power level and how fast power is changing (reactor period or start up rate, 2 different ways of quantifying the rate of power change). PSU is very lucky to have the facility. We got it mainly because the president of PSU at the time was president Eisenhower's brother. It's good to have friends in high places I guess.
Thank you very much for showing. I've driven by the "Nuclear Boobies" (San Onofre) hundreds of times and was always curious about the inside of a reactor. My buddy works for a RO water company and its amazing to see the water so crystal clear.
PLEASE PLEASE PLEASE make more content on radioactivity & Nuclear Physics. I absolutely LOVE the bottom of the periodic table AKA "the Actinide Series." My favorite things include the beautiful blue Cherenkov glow. Well everything that either sheds Alphas to go down the tables scale or Bata that magically turns Stuff Like Neptunium into plutonium
congrats on hitting 1MW, best I can get from mine was 981kw - adding a few more fuel rods when I get home from school tomorrow. I have to work quickly though, this assignment has to be turned by the end of next week.
Wow, such an awesome footage of Cherenkov radiation. I was able to see one in person, in a Polish "Maria" reactor in Świerk (you can google it), but this footage is just freaking awesome. Thanks for the upload, mate.
This video brings back memories of when I was a student and had labs in this building. I remember the first time walking in the building and the astonishment I felt that this reactor is just in a big open pool with no pressure vessel. Awesome video! any chance you'll post video of a reactor pulse?
I have watched this many times recently and am still shocked each time I watch it as to how amazing this truly is and how small it is producing this much power (yes I know it's just a demo)
Very cool video. I just wish you hadn't sped up the startup and shutdown. I for one am a patient guy and it would be nice to see it all in real time. Still, very much appreciated. Plus, it's kinda cool to hear the pumps, because until now I had no idea what a reactor would sound like. I figured the reaction itself would be virtually silent, and most noise would be from the cooling pumps and ancillaries.
You would have to get close to the core to get a lethal dose. If you fell in the water with the reactor operating and were just on the surface, you wouldn't receive much dose at all. In the reactor bay, operating where the reactor is in the video, radiation levels are very very low.
How does this work? I know that in order to produce electricity, the steam generated by the hot rods need to be sent to some kind of turbines. How is the steam generated and collected from this reactor?
all those neutrinos streaming out too ...slipping past the pool, your camera, the university, the planet ... mind blowing. Have any neutrino detectors "seen" your reactor that you are aware of ?
Not that I know of. I have a feeling it would be hard to pick up a 1MW research reactor among all of the power reactors operating around the world and under the ocean.
When you say 1MW and 500kW, what exactly are your meassuing? My understanding is that in power generating reactors this would be a meassurement of the output of tthe turbines given a specific heat output from the reactor. However as you say, you are not in the business of turning turbines so what do you use as your measurement for power? Is it just how much power this would make turning turbines if it had turbines to turn? Great video, thank you for uploading it and taking the time to answer questions. Nuclear power education needs to happen. So sick of people yelling about how its the devil but when you ask them, they don't actually know how it works in the least.
The 1MW and 500kW are thermal power. The reactor is transferring that much heat to the surrounding water. Commercial reactors have both an electrical output rating and a thermal power rating. Most people will know the electrical rating, but the thermal ratings are typically less known. The thermal rating can be estimated by taking the electrical rating and multiplying it by 3.3. So a 1000 MW reactor will be able to output 3300 MW of heat. Converting the heat from the reactor to electricity is only about 33% efficient. We calibrate out instruments by operating at 1MW until the pool reaches a stable temperature, and then calculate the amount of heat leaving the pool through our cooling system.
There is no rankine cycle here. We are simply dissipating all heat to the bulk fluid and then operating a cooling system to transfer it (the heat) to water which goes to the sewer. There is no pressurized primary and secondary system, and were not spinning a turbine.
Yep I picked that up from other comments, I was asking about commercial systems. Above you referenced the efficiency of them, and I was wondering what causes the most significant loss of energy transfer in those systems?
Your comment about prompt critical is interesting (never heard of it before). A video about that would be awesome, just watched WSJ's video showing it but they don't explain much. I never knew the speed at which the rods were removed would cause a spike in power generation, I just figured the rods were just steady state energy producers.
Fantastic video! I was watching the darker area around the edgesof the pool....and kept seeing small flickers of light or something. Is that the energy in the water or is it just the reactor causing interference on the GoPro?
you're pretty good at holding your breath
This is undoubtedly the best video I have seen thus far. Thanks for sharing it.
Alex Laurence Thanks! Maybe I will take some more video of the reactor soon.
NOW I FULLY UNDERSTAND HOW IT ALL WORKS. THANK YOU :)
no need for school
+Moris Doehmann Day be called Cherenkov Radiation. You see The electrons are moving faster than light thru a medium causing a shock wave.(NOT FASTER THAN C OR PHOTONIC VELOCITY IN A VACUME AS NOTHING IS FASTER THAN C)
Great footage, so rare to be able to see something like this, many thanks for sharing it!
You're welcome!
Alex Landress I can tell you're an engineer, English isn't your forte. *you're welcome*.
Lol at the Grammar Nazi. I bet you're super fun at parties 😀
My two cents, in this particular case, I don't think he was really being a grammar Nazi. As a self-admitted grammar Nazi who happens to know many, and be the offspring of, engineers, they do tend to suck at spelling. I saw my dad spell Jurassic "Jurasek" one time. I LOL'd!
Dat nuclear reactor ambient sound at 500kw. Like im in a starship engineering section or something.
That what I was thinking! Looks and sounds so sci-fi. Amazing video.
Nemo Reem i think what you hear is cooking water.
Florian Jaklitsch or boiling water.
Go listen to Elite: Dangerous engine sound clips.
"If this continues to get interest I would be happy to make more videos of the reactor and radiation in general. I enjoy teaching people and changing minds about nuclear power and other technologies."
Yes, please do that, and explain it in the vid!
Beautiful vantage point on the core, and I love how the GoPro camera sensor picks up some occasional direct radiation signals (sparkles), particularly at 1 MW.
In the zoomed in portion at 1MW you can see quite a few of them. It actually took me awhile to recognize it.
The fact that this only has 733 views is a terrible injustice.
More people are watching!
what are the radiation levels?
45k views? 741 upvotes? ;p
AxelPLasg Not bad for a video I didnt even intend on making public
almost 70k
Cherenkov radiation is hauntingly beautiful.
Yo, someone call Thor. We've found the Tesseract
Thank you for filming it! I've always wanted to see what happens near the reactor core.
Amazing to see that. It is just like a giant kettle. You can even spot the control rods being raised and lowered to control the output. Many thanks for sharing.
action at 1:40 and 5:10
Thanks for adding some time stamps. I didn't really expect many people to watch this video, just needed to get the raw footage up for some people to see. Maybe I will actually edit a video with this footage...
YES! please do, this is awesome, and the comment section is as interesting as the video!
something similar to a gamma ray flash at any moment?
We got to see this reactor being fired up in 1992 with our advanced physics class trip. It was the neatest thing, and I still tell people about it. We got to see the wd-40 thread test film and had access to the neutron howitzer to do particle counts. A lot of people are surprised when I tell them there is a nuclear reactor right in State College. That's a cool job you have there.
Arnold's Design cool
Magnificent. it's so beautiful to see how power of atom tamed in such simple and elegant form. Triumph of human mind, but still so much left to achive.
In certain way, this video makes me remember my childhood when I was playing Half-Life, in the Lambda Complex chapter
you can see the radiation as little white dots appearing during the 1MW portion :D
The Cherenkov radiation is so beautiful. I like this video and hope to see more of it.
Holy crap I was not expecting that blue glow! Would I seriously be able to see that with my naked eye!? It looks so incredible it seems fake, really amazing stuff!
"UFO" (Unidentified Floating Object(lol) at 06:40 from left to right mid screen.
This should be a live stream! I think I would not get tired of watching this.... Ever!
Starting at around 7:00, you can see some white flashes, especially as they close in on a portion of the shot. Tiny little one or two pixel sized white flashes. Those are from the radiation hitting the cmos chip right?
It will be exactly that.
oxycontiin you can actually see them the whole time
Cropped, it would make a great screensaver for any device.
The sound.... perfect "white noise" for sleeping.
I love that you can see the radiation effecting the sensors in the camera, the little dots that suddenly pepper the image.
The blue glow is due to the charged particles traveling faster then the phase velocity of light in that particular liquid. You can actually see the huge amount of particles glowing as they are escaping into the surrounding liquid. Awesome.
For those who don't believe this is real, whenever radiation hits a camera you see specs of white because it damages the material inside it, since this is a high quality gopro, the outter shelling blocks alpha and beta radiation, when you see the specs this would be gamma radiation, hence the large amount of water.
It's interesting, eerie and sort of frightening all at the same time. I've finished watching and still feel somewhat freaked.
I worked with reactors in the US Navy, went through training on a submarine prototype that started out in shipyard and made it to another major overhaul in shipyard on an aircraft carrier. Even then, I did not see this level of detail and beauty of a fission reaction. Thanks for the rare treat to see this. BTW, I see some lines that go down towards the core in between the control rods, what are the purpose of those? Also, are you limited to short runs or is there a way to reject heat that I cannot see here?
I was also in the nuclear Navy, submarines though.
The other tubes going down to the reactor are tubes that we can drop experiments down in to, and also some conduit going to temperature detectors in the core.
We can run for long periods of time. There is a cooling system for the pool (not shown). If running at full power, the pool reaches an equilibrium temperature of about 26C.
็Thanks for the footage! Please do take more videos like this. Very educational. Such a rare opportunity to get to see how this thing works. I'd been spending time reading all the top comments and your clarification.
Way, way cool!. I got a tour about 30 years ago when I was student. Only thing missing is a video of a prompt critical event. I was told it looked like a flashbulb going off at the bottom of the pool.
Well done on the video, and THANK YOU to the folks who allowed you to post it on TH-cam.
Is the outgassing part just the water boiling around the rods? Wouldn't steam in those bubbles be radioactive?
There are a few things happening. Above 200kW, nucleate boiling begins to occur on the cladding of the fuel rods. The bubbles from nucleate boiling don't last long. After they break away from the cladding they collapse in the bulk of the fluid channels. This is good for heat transfer.
Many of the bubbles are from the dissociation of water. In the high neutron flux, water is split in to hydrogen and oxygen. Any sort of radioactive isotopes contained in the bubbles either decay or are low level and well under NRC limits.
Thanks, very educational!
Do you have to vent out the hydrogen and oxygen to reduce a risk of fire? Or concentrations are low?
Concentrations are very low. We also have to be running exhaust fans in the reactor bay any time the reactor os operating. If there is a problem with the exhaust system while the reactor os operating, it will automatically shut down.
Because of the small size and low risk, our reactor is not in a containment like a commercial reactor. We have 'confinement,' meaning that the air through the reactor bay is controlled (and kept at a negative pressure) but it is far from air tight. In the event of a high radiation condition, the normal exhaust is automatically shut down and all air leaving the reactor bay goes through a sophisticated filtering system.
how many homes can it power?
looks like the Tesseract from the Avengers :D
nice video.
Thanks! It's pretty cool to see the blue glow.
it's always so impressive to be able to actually see the radiation picked up by the sensor (or film in the old days) in the darker areas!
This is one of the coolest things I have ever seen, thank you for posting!
Actually seeing the Cherenkov radiation glow is amazing. I have never seen a picture of it much less a video. It's like something out of a Science fiction story but real life.
Thanks for posting this. It's fascinating to see a reactor actually operating. Now just to do some research on the differences between your research reactor, the one at NC State University, and the one just up the road from me (Shearon Harris). Thanks again!
Wow, I've wanted to see something like this for decades, nice video!
Thanks!
That thats even a thing is crazy. This video and a friend explaining it answered a lot of questions. Awesome blue glow
I was a reactor operator in the US Navy. This video is probably one of the best videos I have ever seen showing Cherenkov radiation. Really, really awesome video! By the way, I assume this is some test facility somewhere? I have no idea of any facility where you could drop a camera into a pool and film a reactor going critical to 1MW, particularly with it not being in a pressure vessel. This is just freaking awesome!
I was also a Navy reactor operator. This is the research reactor on the Penn State main campus. It's just used as a large neutron source for research and commercial testing.
just been reading your reactions to comments, you get my subscription just for being a nice, interesting guy.
p.s if you do more of these videos, annotation or a voice over of the stages would be interesting. I'm interested but really i don't know what i'm looking at here
Never knew (and still have it hard believing) that a reactor lights up a pretty, but eerie, cosmic blue! I really enjoyed watching this.
Amazing video! You can actually see the control rods going in to shut down the reactor. Thanks for the post, Alex!
Incredible video with excellent quality. Water is so pure it looks like it's not even there
worked with one in 1985-6
This is pretty cool, and certainly unique. Please post more. Some with narration or captions would be great.
I like how you can see little specks of white flash on the screen from the radioactive particles.
I stumbled on this by accident but it has given me an amazing lesson in nuclear power. Thank you. We Are PENNSTATE
I like how you can see the sparkles on the video as the reactor is running, radiation hitting the image sensor :)
When the reactor turns on, you can see little white spots on the camera's sensor from the radiation!! So cool!
Beta particles right? Not gamma rays.
gamma or xrays
this is incredible. I didn't realise you could use a camera film so close to an active nuclear reactor. fantastically interesting
That Cherenkov radiations is just...beautiful. Absolutely stunning. One of the best videos out there hands down.
Only one question - how the hell camera survived the gamma radiation this little beast must output? Or I'm missing something.
Also, how do you handle camera afterwards? I would imagine it could have bits of radioactive decay on it and everything.
The good thing about gamma radiation is that it doesn't make things radioactive like neutron radiation. The camera can handle a lot of gamma radiation before it fails. I would think that the light sensor would fail if exposed to very high gamma flux, but that would really take a lot.
Right, thanks! I thought gamma will still leave things radioactive after exposure.
So, there's no neutron radiation of any kind in this particular reactor? You'd have to fuse or break up elements violently for that to occur I'd imagine.
When gamma rays hit camera sensors, they create bright specs or streaks (depending on the angle compared to the sensor). Look in the darker areas, like the left, and you can see them while it's running. You can watch the gamma exposure happen in real time.
Why is that blue light ? so scary
Bogdan Sdr not scary! Just a natural phenomenon called Cherenkov radiation. Essentially EM radiation from electrons moving faster than light through the water. In water light moves about 75% the speed it does in a vacuum (space).
Alex Landress Thank you for explanation. That blue light is visible to human eye or just a camera can "see" that ?
Bogdan Sdr that blue is visible to the naked eye. It's actually pretty rare to be able to see it in person. At commercial power plants the reactor is in a vessel and it can only be seen during refueling. This reactor is pretty unique
Cherenkov radiation. Electrons from decay moving faster than light through water. I always thought it made a beautiful blue colour. Edited with the correct explanation from Alex below.
and yes this is a unique reactor! thank you for sharing this.
Faster than light in a vacuum ;)
Wow this is fantastic footage. If you notice the random white pixels of light that pop on and off are accentually stray electrons hitting the CCD of the camera and causing an overload on the sensor.
Alex is figuring it's a gamma ray from N16 wandering near the camera and then shedding. But I'm thinking the odds of a gamma ray hitting the sensor are low, whereas an electron has a pretty good chance of being intercepted by the sensor, I'm thinking almost 1 to 1. And flipping the bit to a maximum all white is exactly what we would expect an electron to do.
Would a gamma ray even trip that photonic sensor? If it did, that means a molecule spilled electrons and got damaged, didn't it? Is there damage now to the sensor? Spots maybe?
I like electrons a lot better.
The blue Cherenkov Radiation is beautiful. It never gets boring thinking that small cube radiates 1MW of power. Think ~500 kettles boiling at once. (2 kilowatt each)
Amazing video. Thank you. For those like me who do not really understand what is happening, please do another video explaining soon!
I love this! Please make more videos of the inner workings of a reactor. I have always been curious.
i wish i could meet you one day cause i love your content. KEEP UP THE GOOD WORK!!
I live 16 miles away from one of these and always wondered, thanks.
ANNOTATED VERSION OF THIS VIDEO IS NOW AVAILABLE!! Be amazed by the beauty of nuclear power and learn something new at the same time! I hope you enjoy the new video! (the sound is fixed in the new video also!)
th-cam.com/video/uYrhWO_ZLYw/w-d-xo.html
Alex Landress correct me if I'm wrong, but I am pretty sure the blue glow is just the high energy photons produced by the reaction
A charged particle is required to create Cherenkov Radiation, so a photon itself cannot cause the glow. However, photons from fission can undergo photoelectric effect with electrons in the water and get them moving faster then light through water.
A charged particle is required because there needs to be a magnetic field created. Moving charged particles create a magnetic field, but it usually dissipates quickly back to a neutral state. When the charged particle moves faster than light through water, the magnetic field is created faster than it can return to a neutral state (speed of light) creating a sort of 'pressure' wave of a magnetic field (in sonic boom terms). That phenomenon is what causes the emission of the blue photon that we can see. Its the neutralizing of that compressed EM field.
Alex Landress Hey thanks for share this incredible rare footage. How many rods were used for this cycle? It looked like 2-3.
Alex Landress 1MW is tiny, is this some submarine reactor?
It's a research reactor. Check out the other video linked in this original comment. We use it as a neutron source, not for electricity.
Whats the blue light? And where does the water which is turned into steam go into and out of the reactor?
We do not generate electricity with this reactor, so there is no steam. The 500kW and 1MW are measures of thermal energy, not electrical.
It would be more accurate to say that it tries to go faster than light, but before it can get there, the extra energy is spilled, in the form of more light.
Alex Landress I thought temperature was measured by BTU and electrical current was measured in Watts/Volts/amps.
Heat can be measured in either British Thermal Units, Watts, calories, etc.
In physics, it is usually watts, since that is a cleaner measure of power to do math with, and all power is heat.
(Unless they feel like using joules)
G510Gamer Watts is Power, Voltage is Electrical Pressure, Amps is Current... They are completely different things. Energy is Joules.
Alex, thank you for showing this, and for all the explanations. Highly educational!
Although science and technology are (and need to be) purely rational things, there are always moments of amazement... Once had the opportunity to stand next to the spent fuel pit of a commercial nuclear power plant and will never forget the blue glow of the Cherenkov radiation I saw down there.
Please keep up your outstanding contributions, and best wishes for your career!
Thanks for the clear answers.
1) I didn't know you can have moderator mixed with the fuel. Neat. Sounds like it moves in a self regulating direction. As it heats up the neutrons, it's automatically reducing the neutron cross section. Pretty slick.
2) WOW. Deliberate power excursions. Exciting stuff. I looked up your "prompt critical". Spectacular video there! I see the pipes(?) jumping. Do the high power excursions make noise?
3) Understood.
5) I was just wondering what the control system looks at to know where to position the control rods moment-to-moment. . I think you've really answered what it is, it's the neutron flux since you've explained that the power output can be accurately known using just the neutron flux.
I'm happy to see universities with such nice facilities. Thanks again for sharing.
1) It is very unique to this design of reactor. It's needed because we have the ability to pulse, like you saw in the other video. The negative reactivity feedback in a commercial reactor due to changing of moderator density is a delayed effect. The ZrH response to an up power is more immediate.
2) The pipes you see moving are the control rods. The power excursion doesnt cause any noise directly. We cause the power excursion by pneumatically 'shooting out' a control rod to a specified height. That air is what you heard. We have 4 control rods. 3 are held up by electromagnet and the other is held up by air pressure. To pulse, we go critical on the 3 electromagnetic rods. We then drive a stopper out to a specified point for the air driven rod. When we initiate the pulse in the control system, 85 psi of air is placed under a piston which shoots the rod up against the stopper.
The pulse happens very quickly. The control system scrams all of the rods within 5 seconds of initiating the pulse. That is the second round of noise you hear (air being vented to atmosphere). And you see the control rods drop in to the core (they look like pipes).
5) Correct. The neutron detectors on the back of the core are the primary indication of power. The control system adjusts rod heights based on a few things, but mainly the current power level and how fast power is changing (reactor period or start up rate, 2 different ways of quantifying the rate of power change).
PSU is very lucky to have the facility. We got it mainly because the president of PSU at the time was president Eisenhower's brother. It's good to have friends in high places I guess.
Can you use your go-pro for normal daily tasks now, or does it glow?
The GoPro is fine. Works like a charm, and it's contamination free!
Keith Cress a
I like the tiny light flashes of light as the radiation (presumably beta or gamma particles?) hits the CCD of the camera.
The blue glow is light boom. Photons were slowed down by the water and intensified the brightness.
Freaking awesome, I bet that GoPro is glowing now...
love how you could see the white dots from the radiation on the camera.
Thank you very much for showing. I've driven by the "Nuclear Boobies" (San Onofre) hundreds of times and was always curious about the inside of a reactor. My buddy works for a RO water company and its amazing to see the water so crystal clear.
PLEASE PLEASE PLEASE make more content on radioactivity & Nuclear Physics. I absolutely LOVE the bottom of the periodic table AKA "the Actinide Series." My favorite things include the beautiful blue Cherenkov glow. Well everything that either sheds Alphas to go down the tables scale or Bata that magically turns Stuff Like Neptunium into plutonium
This is easliy one of the coolest videos on the internet. Is that cherenkov radiation? It looks so surreal
congrats on hitting 1MW, best I can get from mine was 981kw - adding a few more fuel rods when I get home from school tomorrow. I have to work quickly though, this assignment has to be turned by the end of next week.
I love that you can see the radiations effect on the GoPros sensor.
Wow, such an awesome footage of Cherenkov radiation. I was able to see one in person, in a Polish "Maria" reactor in Świerk (you can google it), but this footage is just freaking awesome. Thanks for the upload, mate.
This video brings back memories of when I was a student and had labs in this building. I remember the first time walking in the building and the astonishment I felt that this reactor is just in a big open pool with no pressure vessel. Awesome video! any chance you'll post video of a reactor pulse?
The Beautiful Cherenkov glow makes me want to swim down to it.
I have watched this many times recently and am still shocked each time I watch it as to how amazing this truly is and how small it is producing this much power (yes I know it's just a demo)
I would like to see a tour of all of what's up top near the end. Including the rest of the systems for that matter. Very nice vid!
was that a gieger counter you used at the very end of this video?
rdgk1se3019 looks like it
The soothing hue of Cherenkov Blue ...
Why is the energy ommited blue instead of the usual bright orange? I thought the rods got "red hot"
this is amazing I can't believe I am watching something like this. it's a privilege. thank you for sharing with us.
Never seen anything like this thx for the upload 👍👍
Very cool video. I just wish you hadn't sped up the startup and shutdown. I for one am a patient guy and it would be nice to see it all in real time. Still, very much appreciated. Plus, it's kinda cool to hear the pumps, because until now I had no idea what a reactor would sound like. I figured the reaction itself would be virtually silent, and most noise would be from the cooling pumps and ancillaries.
probably one of the most interesting videos ive seen in my life. thanks for sharing.
Would you die of radiation exposure if you were swimming in this coolant water?
You would have to get close to the core to get a lethal dose. If you fell in the water with the reactor operating and were just on the surface, you wouldn't receive much dose at all. In the reactor bay, operating where the reactor is in the video, radiation levels are very very low.
Water makes for excellent radiation shielding as well as a neutron moderator
James Rowland especially when its heavy water.
Alex Landress I still wouldnt swim in it.
One of the bunch wants to lick it, another swim in it....Crazy people.
p.s.
Thanks for the video!
I like how you can see a the small flashes on the camera from the radiaton
The Cherenkov radiation makes it look pleasantly sci-fi. Awesome and quite rare footage!
This is interesting. A pretty antiquated technology as we move to natural fusion, but still cool (and intimidating).
How does this work? I know that in order to produce electricity, the steam generated by the hot rods need to be sent to some kind of turbines. How is the steam generated and collected from this reactor?
Please Do make more videos on the reactor. There are very few videos on TH-cam showing operating reactors.
There are even fewer reactors that are able to be recorded in an operating condition. I will upload more videos in the future.
all those neutrinos streaming out too ...slipping past the pool, your camera, the university, the planet ... mind blowing. Have any neutrino detectors "seen" your reactor that you are aware of ?
Not that I know of. I have a feeling it would be hard to pick up a 1MW research reactor among all of the power reactors operating around the world and under the ocean.
That's cool seeing the control rod being inserted and slowing the reaction
"The beautiful glow" "We need MORE"
Ahh, so awesome. I love the pixel-sized crackles of visible radiation you can see every so often.
Now that's cool. I think this has NC State's reactor beat in the cool factor department.
When you say 1MW and 500kW, what exactly are your meassuing? My understanding is that in power generating reactors this would be a meassurement of the output of tthe turbines given a specific heat output from the reactor. However as you say, you are not in the business of turning turbines so what do you use as your measurement for power? Is it just how much power this would make turning turbines if it had turbines to turn?
Great video, thank you for uploading it and taking the time to answer questions. Nuclear power education needs to happen. So sick of people yelling about how its the devil but when you ask them, they don't actually know how it works in the least.
The 1MW and 500kW are thermal power. The reactor is transferring that much heat to the surrounding water.
Commercial reactors have both an electrical output rating and a thermal power rating. Most people will know the electrical rating, but the thermal ratings are typically less known. The thermal rating can be estimated by taking the electrical rating and multiplying it by 3.3. So a 1000 MW reactor will be able to output 3300 MW of heat. Converting the heat from the reactor to electricity is only about 33% efficient.
We calibrate out instruments by operating at 1MW until the pool reaches a stable temperature, and then calculate the amount of heat leaving the pool through our cooling system.
What are the primary causes of loss in the the system (Rankine cycle right?)
Awesome! Thank you.
There is no rankine cycle here. We are simply dissipating all heat to the bulk fluid and then operating a cooling system to transfer it (the heat) to water which goes to the sewer. There is no pressurized primary and secondary system, and were not spinning a turbine.
Yep I picked that up from other comments, I was asking about commercial systems. Above you referenced the efficiency of them, and I was wondering what causes the most significant loss of energy transfer in those systems?
getting to see this helps provide context for our imagination. very cool
very cool! i thought the rods would be inserted or something. no moving parts?
Your comment about prompt critical is interesting (never heard of it before). A video about that would be awesome, just watched WSJ's video showing it but they don't explain much. I never knew the speed at which the rods were removed would cause a spike in power generation, I just figured the rods were just steady state energy producers.
Stunning to see this! Thanks!
Fantastic video! I was watching the darker area around the edgesof the pool....and kept seeing small flickers of light or something. Is that the energy in the water or is it just the reactor causing interference on the GoPro?
afaik its caused by radiation interfering with the camera. you can see the same flickering in old chernobyl or fukushima footage.
This is really awesome! Thank you so much for sharing.