https://doi.org/10.1051/epjn/2023017
Regular Article
Technical note: stable and unstable reactors
1
Scientific Adviser CEA/INSTN
2
Institute for Safety Problems of NPP, NAS of Ukraine
* e-mail: bertrand.mercier@cea.fr
Received:
14
June
2023
Received in final form:
12
August
2023
Accepted:
15
September
2023
Published online: 24 October 2023
It is well known that a reactor is stable if the core reactivity decreases with the core power. This is the case for many types of reactors, including the PWR. However, this was not the case for the RBMK (Reaktor Bolshoy Moshchnosti Kanalniy) which could be unstable at low power. What does it mean precisely? By using a 2 × 2 system of non-linear ordinary differential equations we show that naturally (i.e. without using the control rods), with the same reactivity injection, if the initial power is lowered, then the final power may be higher, which is a rather unusual behaviour.
© B. Mercier and V. Borysenko, Published by EDP Sciences, 2023
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
