Nuclear Reactivity Calculation with Reduction of Fluctuations

This article presents a study based on a series of numerical experiments. It demonstrates the possibility of reducing fluctuations in the calculation of reactivity using the second Bernoulli number based on the approximation of the Euler-Maclaurin formula. This approach requires knowledge of the first three derivatives, which are implemented progressively. The fluctuations are assumed to occur around an average value of the neutron density with a Gaussian distribution. Jitter reduction is performed with a first-order delayed low-pass filter for different forms of neutron population density, with different time steps and with different filter constants. The numerical results show that the method can be used as a digital reactivity meter.