Evaluating the neutronic state (neutron flux, power . . . ) of the whole nuclear core is a very important topic that has strong implication for nuclear core management and for security monitoring. The core state is evaluated using measurements and calculations. | Nuclear core activity reconstruction using heterogeneous instruments with data assimilation EPJ Nuclear Sci. Technol. 1 18 2015 Nuclear Sciences B. Bouriquet et al. published by EDP Sciences 2015 amp Technologies DOI epjn e2015-50046-1 Available online at http REGULAR ARTICLE Nuclear core activity reconstruction using heterogeneous instruments with data assimilation Bertrand Bouriquet Jean-Philippe Argaud Patrick Erhard and Angélique Ponçot Électricité de France 1 avenue du Général de Gaulle 92141 Clamart cedex France Received 28 July 2015 Received in final form 8 October 2015 Accepted 20 November 2015 Published online 18 December 2015 Abstract. Evaluating the neutronic state neutron flux power . . . of the whole nuclear core is a very important topic that has strong implication for nuclear core management and for security monitoring. The core state is evaluated using measurements and calculations. Usually parts of the measurements are used and only one kind of instrument is taken into account. However the core state evaluation should be more accurate when more measurements are collected in the core. But using information from heterogeneous sources is at glance a difficult task. This difficulty can be overcome by Data Assimilation techniques. Such a method allows to combine in a coherent framework the information coming from numerical model and the one coming from various types of observations. Beyond the inner advantage to use heterogeneous instruments this leads to obtaining a significant increase of the quality of neutronic global state reconstruction with respect to individual use of measures. In order to describe this approach we introduce here the basic principles of data assimilation focusing on BLUE Best Unbiased Linear Estimation . Then we present the configuration of the method within the nuclear core problematic. Finally we present the results obtained on nuclear measurements coming from various instruments. 1 Introduction Secondly .
