Thanks to the unusual but experts around the world capable of documenting the situation apparently were demanding art of nuclear forensics. In decades they have lit very well the hidden workings of nuclear power plants from a distance, turning the piece of paper is information in detailed analyses.
For example, an analysis by a French energy company found very much about the State of the plant reactors always have described as the Japanese: water levels in the reactor cores drop by as much as three quarters and temperatures in the cores to almost 5,000 degrees Fahrenheit in the fast, hot enough to burn and melt the zirconium case, which protect the fuel rods.
Scientists in Europe and America know also from observing the explosions of hydrogen gas in the work, that the nuclear fuel rods had heated very dangerous and extent dissolved the rods of radioactive plumes.
At the same time, the reviews also show that escaped the reactors at Fukushima Daiichi of the deadliest results - a complete meltdown of the plant.
Most of these computer-based forensics systems were developed after the 1979 partial meltdown in three mile Iceland, happened when regulators found, you are essentially blind in the reactor. Because to meet company, then to regulatory authorities, the nuclear power stations work snippets use of information, carrying out what is happening in developing and plenty of risk evaluations from a plant, simulations.
In fact, the detailed assessment of the Japanese reactors, which were the Energy Secretary Steven Chu on Friday - when he told reporters that the core of a reactor was damaged which had over 70 percent, and that a further reactor had a 33 percent meltdown subjected - came from forensic modelling.
The bits of information that drive these analyses range from the simple to the complex. You can include the time everything from the length, which lacked a reactor core cooling water to the intricacies of the gases and radioactive particles emitted from the plant. Engineers incorporated the data points in computer simulations of detailed portraits of imperceptible, including many features of code changes to the melting of the hot fuel cores.
Governments and companies now have dozens of these independently developed computer programs, known in industry jargon as "security code." Many of these institutions - including in Japan - set to forensic modelling the disaster of Fukushima Daiichi planning for a number of activities, from evacuations to the forecast of probable result analyze.
"The code was better and better" after the accident at the three mile Iceland reveals the poor condition of the reactor review, said Michael W. Golay Professor of nuclear science and technology at the Massachusetts Institute of technology.
These portraits of the Japanese disaster tend to be proprietary and confidential, and in some cases secret. The reviews enormously sensitive for industry and Government are one of the reasons is the lack of precedent: the atomic age has the construction of nearly 600 civilian power plants seen, but according to the world nuclear Association, only three major accidents in which were melted down their fuel cores.
Now, due to a crisis in Japan, the Atomic simulations suggest that suddenly, with three reactors in the Prefecture of Fukushima Daiichi complex in a phase of collapse has doubled the number of serious accidents.?Even so, the public authorities wanted to grim technical details to avoid, that could cause alarm or even panic.
"they want not to go there", said Robert Alvarez, a nuclear expert who was a consultant of energy ministers from 1993 to 1999. "The spin is about reassurance."
Carry on if as three mile Iceland in Pennsylvania could development of events in Japan, the forensic modelling for some time. It took more than three years before engineers visually inspect a camera to the damaged core of the reactor Pennsylvania lowered, and a further year, to map the extent of the damage. The core turned out to be about half are melted.
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