Verification of kinetic capabilities of the GNOMER neutron diffusion code. (November 2017)

• Record Type: Journal Article
• Authors: Merljak, Vid; Kromar, Marjan; Trkov, Andrej
• Is Part Of: Annals of nuclear energy. Volume 109(2017:Nov.)
• Page Start: 431
• Page End: 439
• Publication Date: 2017-11
• Subjects: Reactor kinetics -- 3D simulation -- Computer code -- Verification -- Diffusion theory; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2017.04.037
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: GNOMER 3D neutron diffusion code was updated with the capability to perform kinetic simulations. Implementation is discussed in detail and points for further development are given. For code verification two test cases are used: point kinetics and control rod insertion into a typical PWR core. Both the normal mode (using implicit iterations) and the so called Lambda mode yield consistent results. Abstract: Recently, the GNOMER neutron diffusion code was updated to support kinetic simulations. This direct approach to reactor kinetics is further branched into two operational modes: the so-called Lambda mode and the (normal) implicit mode. Both approaches are described in detail. Also, calculation of point kinetic parameters is implemented and discussed. To verify GNOMER's new kinetic capabilities, two numerical tests are considered; namely, the point kinetic test case and a rod insertion simulation on a model of a typical pressurised water reactor (PWR). The reference solutions were produced by a point kinetic script and the SKETCH-N diffusion code, respectively. Very good agreement is found for all cases considered. Unusual behaviour and discrepancies – where observed – are explained satisfactorily. With the evidence provided in the paper, GNOMER is deemed to be a reliable tool for (both static and) dynamic simulation.