Burg spectrum estimation of neutron noise for the monitoring of reactor internal vibration with a hypothesis test

Traditionally, non-parameter spectrum estimation has been widely used in th e analysis of neutron noise obtained from ex-core detectors for reactor str ucture monitoring. Because a limited data results in a severe bias, the res olution is not adequate for a monitoring application. The Burg spectrum est imation of the parameter method distinctively traces the modes of the react or's internal structures with the order of 160 tested by chi(2) (chi) distr ibution and F distribution. Fuel 1st mode, 2nd mode, beam mode and shell mo de in association with a reactor' a internal vibration are more discernable than the spectrum estimator method proposed in ASME-OM/SG part 5 with the neutron noise signals of Ulchin 1. The result gives us the early informatio n of the joint condition between thermal shield and core support barrel. (C ) 2000 Published by Elsevier Science Ltd. All rights reserved.