The natural catastrophe at Fukushima Dai-ichi 2011 enlightened the nuclear community. This study reveals the non-negligible risks regarding the short term storage of spent nuclear fuel. The study has also investigated the possibility of using natural circulation of air in a passive safety system to cool the spent nuclear fuel pools.
The results where conclusive: The temperature difference between the heated air and ambient air is far too low for natural circulation of air to remove any significant amount of heat from the spent nuclear fuel pool in a worst case scenario. Air, as with any gas, has too low density and a specific heat too low to be able to remove the heat generated by spent nuclear fuel shortly after it has been removed from the reactor core.
The author does not deny the possibility of slightly prolonging the boiling with other designs. The author does however suggest other possibilities to prolong cooling with the conclusion that large enough spent fuel pools would constitute the simplest solution.
Author: Nimander, Fredrik