Containment vessels held: simulation test, Japan Times, Dec. 1, 2011:
The primary containment vessels of reactors 1, 2 and 3 at the Fukushima No. 1 power plant probably managed to contain the melted nuclear fuel, according to the findings of a Tokyo Electric Power Co. computer simulation released Wednesday. [...]
“the melted fuel remained inside the containment vessels,” Tepco said in a report on the simulation’s findings [...]
Simulation based on projections by Tepco, using program from nuclear industry giant Westinghouse
Tepco said the calculations were based on the pessimistic [???] assumption that 100 percent of the fuel in reactor 1 melted through the pressure vessel and into the primary containment vessel, and that 57 percent of the nuclear fuel in reactor 2 and 63 percent of the fuel in reactor 3 penetrated through to the containment vessels.The simulation also was based on projections Tepco made, including its calculations of the decay heat released by the melted nuclear fuel. The utility used the Modular Accident Analysis Program developed by Fauske & Associates LLC, a subsidiary of U.S.-based Westinghouse Electric and a pioneer in computer models that analyze severe accidents at nuclear power plants.
The temperatures in the containment vessels and at the bottom of the pressure vessels have been stable and recently measured less than 100 degrees as of Wednesday.
The temperatures in the containment vessels’ concrete floors, however, are not known.
Published: November 30th, 2011 at 7:42 pm ET
- *NEW Dec. 1 Yomiuri* Gov’t Study: Reactor pressure vessel may be “tilted” after corium melted through concrete floor up to 200 cm deep November 30, 2011
- AP: New gov’t study rasies possibility of “structural damage to reactor’s foundation” — Erosion of concrete could be deeper than Tepco claims December 1, 2011
- Report: If fuel melted through reactor, it would react with concrete floor of primary containment — Could add significantly to total radiation release May 23, 2011
- NHK: “This is a very severe accident” — Nuclear fuel at Reactor No. 1 may have melted through 65 cm of concrete… Only 37 cm at thinnest point (PHOTOS) November 30, 2011
- “Emergency measures” taken at Fukushima plant after “unexpected dents” found on reactor building floor — Situation “much worse than expected” — Experts: It’s like a “burning house”… “I was shocked” by outcome… “Streaming of radiation” may be underway February 27, 2017