|Occupational Safety and Health|
The worst case reactor accident (in terms of widespread distribution of respirable radioactive release) is NOT (usually) melt through the basemat -it's a steam explosion /fci firing the head through the containment (alpha mode failure in Rasmussen's WASH1400 nomenclature)
- Can that nomenclature be found online? It'd be good to reference it. I was viewing the melt-through-the-basement as a preliminary to a steam explosion having the same effect, plus groundwater contamination, but I have no real analysis behind that. So if you want to update it, please do! And it'd be nice to have a (grim) article on Nuclear reactor failure modes... --Andrew 21:33, Dec 15, 2004 (UTC)
What IS a steam explosion??
The latest addition by Malarky apparently makes a steam explosion synonomous with any rapid expansion of superheated water - whilst I'm not in principal to this phenomenon being discussed, it's not what I understood by the term (by a long way). After an appropriate invitaion for discussion, I would wish to revert the change. Bob aka Linuxlad 22:21, 31 October 2005 (UTC)
The folling is part of the message I alread sent ot Linuxlad:
Short Version: Approximately 950PSI, 850F water inside boiler reached the furnace, which is hot enough to make cro-moly high temperature steel glow cherry red, which is at most at 30PSIA. The biggest problem I saw was that the article said most of these explosions are caused from lava hitting water, but man has been blowing up boilers in tugboats since at least 1860.
Part of damage to boiler. http://img495.imageshack.us/my.php?image=expansionjoint1kt.jpg
Outside Diameter:2”, Thickness:.134”, Name: Frontwall Tube http://img3.imageshack.us/my.php?image=explodedtube4xb.jpg
The above boiler explosion was water tube.
I may be wrong that a Steam Explosion is not violent enough to be part of that article, however you'll find that old firetube boilers used roughly in the years 1860s-1940s (not exact years, probably a little earlier on both years) were known for disintegrating the entire wooden ship in the event of an explosion. Hence the start of federal inspections of them.
Malarky 23:30, 31 October 2005 (UTC)
Well you can certainly get a fair old crack out of a layer of superheated water formed at/after a quench front with a hot surface. But the sort of things that people usually talk of here appear to rely on much higher heat transfer areas than are available from a normal solid interface like a boiler tube. There was a lot of high-speed camera work (10,000fps or better) done about 25 years back, which seemed to show that, in simulated foundry accidents (_molten_ metals and water), the materials roughly intermixed on a cm scale but stably film boiling initially - then, crack, a shock front went through, and all the hot material got fragmented and gave up its heat across a very large heat transfer area, in a few milliseconds. The results, especially in a foundry, wrought havoc. And you could sweep the fine debris up afterwards.
Lets try and use your material, but not to so take over the piece as it's presently written. Certain of the key phenomena are the same but the key step, self-sustaining fine fragmentation, is not. Linuxlad
Steam explosion in refinery distillation columns
This happens fairly often at oil refineries. If "wet" steam is allowed to enter a distillation column the hot oil will flash the liquid water and the steam produces enough pressure to dislodge all the trays. This doesn't cause the column to explode or anything, but it does mangle the steel trays requireing a shut down and a few weeks of work to repair.
- Possibly in vulcanology, such as Hawaii, where magma injected into seawater is an important and distinctive process, giving rise to pillow lavas. Otherwise it's a new one on me and does look dubious. Andy Dingley (talk) 02:04, 24 February 2010 (UTC)
- Overall, the whole article seems to lump together boiler explosions, nuclear reactor accidents and vulcanology as if they were the same thing. They clearly aren't, even if "steam" and "explosions" are involved in all. Andy Dingley (talk) 02:06, 24 February 2010 (UTC)
- Sure, it might be a bona fide term of art in vulcanology—the phenomenon is discussed in the article and illustrated by the image—but it's surely no synonym for "steam explosion". The introduction claims it is. I think that part should be removed or rephrased. 18.104.22.168 (talk) 23:57, 25 February 2010 (UTC)
The Chernobyl Disaster was the product of one or more steam explosions. I have read that the intensity of the second explosion was such that it mught have been a hydrogen explosion, caused by the mixture of super hot graphite from the reactor core and steam. Much of this is, of course, conjectural but steam obviously played a major role and it is possible that hydrogen was also a part of the second explosion. Flanker235 (talk) 09:40, 27 September 2022 (UTC)