SENSITIVITIES OF SOME CHARACTERISTICS OF NUCLEAR EQUILIBRIUM STATE TO ONE-GROUP CONSTANTS

摘要

In the nuclear equilibrium state, the nuclide densities and h-value (a neutron balance index) can be estimated from one-group nuclear constants. One-group cross sections usually contain some uncertainties originated from nuclear data errors, analysis errors and design uncertainties. The method to obtain sensitivity coefficients of nuclide densities and h-value to one-group constants are derived by the use of perturbation method, and some numerical results are obtained for both fast and thermal reactors. The numerical results show several notable characteristics. It is appeared that many of these characteristics can be explained using only the main nuclide chain. The method developed in this paper, some derived characteristics and/or numerical results for typical reactors may be useful for future studies based on the nuclear equilibrium state. [References: 9]