A method for correlated random sampling is presented. Representative samples for multivariate normal or log-normal distribution can be produced. Furthermore, any combination of normally and log-normally distributed correlated variables may be sampled to any requested accuracy. Possible applications of the method include sampling of resonance parameters which are used for reactor calculations
COBISS.SI-ID: 26034215
Characterization and optimization of irradiation facilities in a research reactor is important for optimal performance. Nowadays this is commonly done with advanced Monte Carlo neutron transport computer codes such as MCNP. However, the computational model in such calculations should be verified and validated with experiments. In the paper we describe the irradiation facilities at the JSI TRIGA reactor and demonstrate their computational characterization to support experimental campaigns by providing information onthe characteristics of the irradiation facilities.
COBISS.SI-ID: 25458727
Potential formation in front of a floating electron emitting electrode immersed in a plasma composed of one positive ion species and electrons was studied by PIC simulation using the XPDP1 code. A method for correct normalization of simulation results is presented and based on this the simulations are compared to the kinetic model. The model is valid in the regime of temperature limited electron emission and in this area the matching of the model and simulations is excellent. Above the temperature limited emission boundary the model is not valid, but the simulations indicate, that the floating potential of the electrode remains almost constant up to the emission that exceeds the temperature limited emission for about 50 percent. The results are relevant for possible use of emissive probes in small tokamaks.
COBISS.SI-ID: 8905300
Two neutronics experiments have been carried out at 14 MeV neutron sources on mock-ups of the helium cooled pebble bed (HCBP) and the helium cooled lithium lead (HCLL) variants of ITER test blanket modules (TBMs). These experiments have provided an experimental validation of the calculations of the tritium production rate (TPR) in the two blanket concepts and an assessment of the uncertainties due to the uncertainties on nuclear data. This paper provides a brief summary of the HCPB experiment and then focuses in particular on the final results of the HCLL experiment. The TPR has been measured in the HCLL mock-up irradiated for long times at the Frascati 14 MeV Neutron Generator (FNG). Redundant and well-assessed experimental techniques have been used to measure the TPR by different teams for inter-comparison. Measurements of the neutron and gamma-ray spectra have also been performed. The analysis of the experiment, carried out by the MCNP code with FENDL-2.1 and JEFF-3.1.1 nucleardata libraries, and also including sensitivity/uncertainty analysis, shows good agreement between measurements and calculations, within the total uncertainty of 5.9% at 1-sigma level.
COBISS.SI-ID: 26167847