In this study we derived a new one-point equation based on the balance of fission neutrons. The equation has the same form as the conventional equation using keff which represents the neutron balance in the whole core. The variables of the new equation are the number of fission neutrons and delayed neutron precursors, and the coefficients are the multiplication rates of prompt fission neutrons, delayed neutrons and source neutrons. In the conventional equation, the variables are weighted by the adjoint flux; in other words, they are adjusted to the critical state. The variables in the new equation correspond to actual values even in a deep subcritical state; hence, the physical meaning of each term is clear.The dynamic behavior of a slab core with an external source was analyzed through calculations based on the new equation. Deterministic and probabilistic calculations of the equation were performed for a typical accelerator-driven system in the static state.
- Accelerator-driven system
- Multiplication rate
- One-point equation
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Nuclear Energy and Engineering