Jorge Stolfi
2011-03-23 02:40
The following plots show the partial evolution of physical quantities in the Fukushima Daiichi reactors #1, #2, and #3, during a the march/2011 incident. Note that the incident started on 2011-03-11 (friday), two days before the start of the plots.
This quantity is the water level, inside the (inner) reactor pressure vessel, in millimeters, measured from the top of the fuel elements. Negative values mean that the fuel is partly out of the water.
This quantity is the pressure in the inner reactor pressure vessel, in kilopascals (kPa). A value of zero means the same as outside air pressure. Note that 100 kPa is aproximately 1 bar (one atmosphere).
This quantity is the pressure (kPa) in the "drywell", the outer steel container that surrounds the reactor. A value of zero means the same as outside air pressure.
This quantity is the pressure (kPa) in the suppression container, the toroidal (donut-shaped) chamber below the drywell container. A value of zero means the same as outside air pressure.
This quantity is the temperature (Celsius) at the bottom of the reactor's (inner) pressure vessel. Note:The value is multiplied by 10 for clarity. Note that the sensor's top-of-scale reading is 400 C, which was briefly exceeded on some occasions.
The water level and pressure data through 2011-03-11 come from the PDF document titled 'Condition of the plants of the unit 1-3 at FI site', fetched from the Nuclear Information and Resource Service site on 2011-03-22. That site says
Here is a document on the condition of Units 1, 2 & 3 from March 13-17, showing water levels and containment pressure, obtained through Citizens' Nuclear Information Center in Tokyo.
The data from that document was reformatted by hand into the text file.
The gaps in the plots are data points that were blank or in the original document.
Data from 2011-03-22 onwards comes from the Nuclear and Industrial Safety Agency (NISA) news Releases.
For further information please contact the document authors.
The temperature readings from 2011-03-19 06:30 to 2011-03-22 15:30 were obtained from a scanned worksheet presumably prepared by TEPCO. After 2011-03-22 the data weer taken from the NISA bulletins (see above). The data was entered by hand to a separate text file.
The plots were created by a gnuplot-based Linux shell script.
IMORTANT: These plots, scripts, and data files are provided "as is", for the reader's convenience, with no guarantee whatsoever. There may be errors in the original document and/or in my processing of it. This page is not an official document of the State University of Campinas (UNICAMP). Neither me nor UNICAMP should be held responsible for any damages that may result from the use of this information. Corrections and suggestions are welcome.
Last edited on 2011-03-24 06:30:24 by stolfi
