Recent content by MikeIt

Just a guess but shiny metal in the drywell could be mirror insulation. There's a fair amount of it. It's not out of the realm of possibility that the dynamic forces that resulted from the breach of the RPV by core debris also tore up some of this insulation and deposited some of it where the...

BWR water level instruments sense differential pressure between a reference leg (which taps off the upper part of the RPV and is filled and held at a constant level by steam condensing in the leg) and a variable leg (which taps off the lower part of the RPV). The article is trying to say that...

Typically, BWRs use their high range drywell or torus area radiation monitors to estimate % core damage. Often they are called Containment High Range Area Radiation Monitors or CHARMS. These are seven or eight decade, logarithmic meters that have a bug source to keep a reading onscale since...

Thanks for the link to the pdf. Shows the importance of ensuring all efforts are made to cool the core and core debris while it is still in the RPV! The explosions at U1, 2 and 3 all seem too closely associated with the actions taken to vent the PC. U3 PC was vented sometime early in the...

Right on, NUCENG. Japan has admittedly stated they assessed severe accident management studies from other nations in the early 1990s, U.S. BWRs included, and thought they took the best guidance combined with their own studies. My observation is their emergency operating procedure and severe...

RPV bottom head failure in a severe accident, according to US BWR beliefs, will occur in an ablating fashion. Uncooled core debris in contact with the inside of the RPV bottom head is likely to penetrate the head at an incore instrument penetration or CRDM housing penetration. When this occurs...