%0 Journal Article
%T Sensitivity Analysis of the TRIGA IPR-R1 Reactor Models Using the MCNP Code
%A C. A. M. Silva
%A J. A. D. Salom¨¦
%A B. T. Guerra
%A C. Pereira
%A A. L. Costa
%A M. A. F. Veloso
%A M. A. B. C. Menezes
%A H. M. Dalle
%J International Journal of Nuclear Energy
%D 2014
%R 10.1155/2014/793934
%X In the process of verification and validation of code modelling, the sensitivity analysis including systematic variations in code input variables must be used to help identifying the relevant parameters necessary for a determined type of analysis. The aim of this work is to identify how much the code results are affected by two different types of the TRIGA IPR-R1 reactor modelling processes performed using the MCNP (Monte Carlo N-Particle Transport) code. The sensitivity analyses included small differences of the core and the rods dimensions and different levels of model detailing. Four models were simulated and neutronic parameters such as effective multiplication factor ( ), reactivity ( ), and thermal and total neutron flux in central thimble in some different conditions of the reactor operation were analysed. The simulated models presented good agreement between them, as well as in comparison with available experimental data. In this way, the sensitivity analyses demonstrated that simulations of the TRIGA IPR-R1 reactor can be performed using any one of the four investigated MCNP models to obtain the referenced neutronic parameters. 1. Introduction The TRIGA IPR-R1 research reactor, located at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) sponsored by Comiss£¿o Nacional de Energia Nuclear (CNEN) in Belo Horizonte, Brazil, operates since 1960 and it has been an important source of experimental data used in the processes of verification and qualification of several modelling processes of neutronic and thermal-hydraulic codes. Furthermore, the Laboratory for Neutron Activation Analysis of CDTN has been responsible for 70% of the analytical demand using the method of neutron activation analysis, established since 1995. Tests confirmed that the TRIGA IPR-RI reactor presented suitable characteristics to apply the method, mainly due to its stable and homogenous neutron fluxes. At that time, due to the symmetry of the core configuration and the rotary rack, no variations in neutron flux distribution in different channels were taken into account. The average thermal and epithermal fluxes were determined in the reactor rotating carousel facility (CF) [1, 2]. However, the reactor core configuration was changed in 2001 to enable a future power increase from 100 to 250 kW. This change consisted of four fuel rods added to the core, replacing the graphite dummy elements in the circular TRIGA core configuration [3]. In this configuration, the axial and radial neutron fluxes have not been measured and there are no experimental data about these
%U http://www.hindawi.com/journals/ijne/2014/793934/