from 28 June 2015 to 3 July 2015 (Africa/Johannesburg)
SAIP2015 Proceeding published on 17 July 2016
The Impact of Re-homogenisation for Nodal Cross-section Corrections in OSCAR-4 as Applied to SAFARI-1 Research Reactor
Presented by Mr. Eric CHINAKA on 1 Jul 2015 from 14:00 to 14:20
Type: Oral Presentation
Track: Track B - Nuclear, Particle and Radiation Physics
Calculational support to the operation of the SAFARI-1 research reactor at Necsa is primarily performed with the in-house developed OSCAR-4 nodal diffusion code. Nodal diffusion methods implement a series of non-linear corrections to the nodal cross-sections. Such corrections are needed since nodal cross-sections are most-often generated in a typical infinite assembly environment, as opposed to the actual core environment. In this work, the impact of one such correction method, termed nodal re-homogenisation, is evaluated for the case of the SAFARI-1 reactor. Furthermore, this is done with respect to a newly proposed OSCAR-4 SAFARI-1 core model. The new model is based in part on nodal cross-sections generated from the Monte Carlo based Serpent code, which supplies a consistent reference transport solution against which the capability of the non-linear model may be measured. The capability of the homogenization model to correct for the environmental error is evaluated on a SAFARI-1 fresh core 2D model, considering both an All-Rods-In (ARI) and an All-Rods-Out (ARO) case. Such analysis has as yet not been applied to research reactors and in this work, we show that the environmental error for a SAFARI-1 core may be as large as 536 pcm and induce a maximum assembly power error of 9.2%. Both cases are then re-calculated, with the re-homogenisation model activated, to illustrate the capability of the re-homogenization correction method.
Dr R. Prinsloo, email@example.com