Robot finds possible melted nuclear fuel at Fukushima - Sensationalist Headlines

[QUOTE=Morgen;52507663]In what other industry can companies be broadly trusted to do the right thing without being forced to?[/QUOTE] I got a whole list right here:

Facepunch is such a groupthink place, say anything that isn't groupthink and you get banned. [editline]31st July 2017[/editline] Did I offend anyone? Lick my balls. [editline]31st July 2017[/editline] I didn't even notice but if you are going to be that, way I implore you to lick 'em good, get all of that ball juice in your stomach. [editline]31st July 2017[/editline] [url]https://en.wikipedia.org/wiki/Background_radiation#Nuclear_accidents[/url] [highlight](User was permabanned for this post ("ASSUMING DIRECT CONTROL" - Sgt Doom))[/highlight]

[QUOTE=coreym;52526849]Facepunch is such a groupthink place, say anything that isn't groupthink and you get banned. [editline]31st July 2017[/editline] Did I offend anyone? Lick my balls. [editline]31st July 2017[/editline] I didn't even notice but if you are going to be that, way I implore you to lick 'em good, get all of that ball juice in your stomach. [editline]31st July 2017[/editline] [url]https://en.wikipedia.org/wiki/Background_radiation#Nuclear_accidents[/url][/QUOTE] Congratulations, you pulled up a wikipedia page after googling "nucular acident" Could you find an actual source?

[img]http://4.bp.blogspot.com/-eB8cFdYiHiY/Ul15wmOBaYI/AAAAAAAAu00/FRyk-Y_is60/s1600/us-nrc-japan-fallout-map-from-destroyed-fukushima-daiichi-nuclear-plant.jpg[/img] [editline]31st July 2017[/editline] what like on those 100 page studies that you can pay for that are on google scholar? or like a news article? you know you are stupid, right?

[QUOTE=coreym;52526867][img]http://4.bp.blogspot.com/-eB8cFdYiHiY/Ul15wmOBaYI/AAAAAAAAu00/FRyk-Y_is60/s1600/us-nrc-japan-fallout-map-from-destroyed-fukushima-daiichi-nuclear-plant.jpg[/img] [editline]31st July 2017[/editline] what like on those 100 page studies that you can pay for that are on google scholar? or like a news article? you know you are stupid, right?[/QUOTE] There have been 2 meltdowns in history. Both occurred because of some form of corruption. Chernobyl melted down because they were doing a reactor test and they disabled all of the safety systems [I]and[/I] the supervisor pushed the reactor way beyond what was considered safe. Fukushima happened because TEPCO was told there was a tsunami flood could lead it a meltdown but ignored warnings because they didn't want to spend money on a levee, and the regulators were corrupt and didn't force action because doing so may harm a potential carreer with TEPCO in the future. Both of these were completely avoidable, by some standards they're not even accidents because they were caused by the men in charge intentionally ignoring important safety information.

[QUOTE=coreym;52526867][IMG]http://4.bp.blogspot.com/-eB8cFdYiHiY/Ul15wmOBaYI/AAAAAAAAu00/FRyk-Y_is60/s1600/us-nrc-japan-fallout-map-from-destroyed-fukushima-daiichi-nuclear-plant.jpg[/IMG] [editline]31st July 2017[/editline] what like on those 100 page studies that you can pay for that are on google scholar? or like a news article? you know you are stupid, right?[/QUOTE] [URL]http://www.snopes.com/photos/technology/fallout.asp[/URL] [url]http://www.snopes.com/photos/technology/fukushima.asp[/url] How embarrassing.

[QUOTE=coreym;52526867][img]http://4.bp.blogspot.com/-eB8cFdYiHiY/Ul15wmOBaYI/AAAAAAAAu00/FRyk-Y_is60/s1600/us-nrc-japan-fallout-map-from-destroyed-fukushima-daiichi-nuclear-plant.jpg[/img][/QUOTE] [QUOTE]300 Rems[/QUOTE] What the fuck is that garbage? 300 rem is fucking 3 sieverts, which is a [b]lethal[/b] dose of radiation. That didn't happen. [editline]1st August 2017[/editline] [QUOTE=Mr. Someguy;52526986]Chernobyl melted down because they were doing a reactor test and they disabled all of the safety systems [I]and[/I] the supervisor pushed the reactor way beyond what was considered safe.[/QUOTE] Actually there was another critical part: the reactor design was inherently garbage, in some cases when you try to lower the reactivity it actually does the opposite, which can lead to a meltdown very easily. Also IIRC the station operators weren't properly made aware of this particular quirk during their training (which wouldn't surprise me at all considering this was USSR).

There was also the issue of positive void coefficient; increases in reactor power cause the coolant to boil, which reduces the neutron dampening effect of the coolant, which increases the reactor power level, which causes more boiling.

Fukushima reactors were BWR though, which have a negative void coefficient. IIRC there aren't too many reactors with positive void coefficients left. Chernobyl is the big example of what positive void coeff can do. [editline]2nd August 2017[/editline] whoops i should probably read more than two words before posting

[QUOTE=papkee;52530176]Fukushima reactors were BWR though, which have a negative void coefficient. IIRC there aren't too many reactors with positive void coefficients left. Chernobyl is the big example of what positive void coeff can do.[/QUOTE] Yes... and we're talking about Chernobyl here.

[QUOTE=mijyuoon;52527836]Actually there was another critical part: the reactor design was inherently garbage, in some cases when you try to lower the reactivity it actually does the opposite, which can lead to a meltdown very easily. Also IIRC the station operators weren't properly made aware of this particular quirk during their training (which wouldn't surprise me at all considering this was USSR).[/QUOTE] [QUOTE=download;52527890]There was also the issue of positive void coefficient; increases in reactor power cause the coolant to boil, which reduces the neutron dampening effect of the coolant, which increases the reactor power level, which causes more boiling.[/QUOTE] The problem (besides trying to run the coolant pumps on turbine wind-down residual power) was that the control rods were graphite tipped. Graphite is an EXCELENT neutron moderator, which means that as you're lowering the control rods, the section where the graphite is actually increases in activity before the neutron absorbing material gets there. This causes a reaction spike, which causes even more heat, which creates the steam voids in the core. Steam is also an EXCELLENT neutron moderator. So lowering the control rods without enough coolant flow caused a chain reaction where there wasn't enough neutron absorbing material, which created more heat, which created more neutron moderators, and that cycle continued until the steam pressure blew the roof off of the unit.

i have a buoy that floated all way from Japan i think i found it a few month after the tsunami or a year after i don't remember i know i found it after the tsunami most likely possibly maybe radioactive [t]http://i.imgur.com/DlycjAm.jpg[/t]

[QUOTE=Silence I Kill You;52530550]The problem (besides trying to run the coolant pumps on turbine wind-down residual power) was that the control rods were graphite tipped. Graphite is an EXCELENT neutron moderator, which means that as you're lowering the control rods, the section where the graphite is actually increases in activity before the neutron absorbing material gets there. This causes a reaction spike, which causes even more heat, which creates the steam voids in the core. Steam is also an EXCELLENT neutron moderator. So lowering the control rods without enough coolant flow caused a chain reaction where there wasn't enough neutron absorbing material, which created more heat, which created more neutron moderators, and that cycle continued until the steam pressure blew the roof off of the unit.[/QUOTE] Steam is not that good a neutron moderator, it's too low density making it far worse that water as a neutron moderator. In the case of RBMK reactors, the core geometry meant the water had a greater neutron dampening effect than moderating effect, meaning boiling of coolant caused an increase in reactor power. This is known as a positive void coefficient.

[QUOTE=coreym;52526867][img]http://4.bp.blogspot.com/-eB8cFdYiHiY/Ul15wmOBaYI/AAAAAAAAu00/FRyk-Y_is60/s1600/us-nrc-japan-fallout-map-from-destroyed-fukushima-daiichi-nuclear-plant.jpg[/img] [editline]31st July 2017[/editline] what like on those 100 page studies that you can pay for that are on google scholar? or like a news article? you know you are stupid, right?[/QUOTE] can we have this printed out and stuck in a frame? I just love everything in this post - a "source" which is an image macro filled with inaccuracies which doesn't cite a source ( I bet coreym doesn't even know what a rem is), and then a beautiful comment discrediting scientific studies, followed up by a hilariously hypocritical insult. Wow. I'd like to redact my previous statement about the failure of the backup generators, turns out I was wrong and have been corrected by the other members here.