Correction methods for pulsed neutron source reactivity measurement in accelerator driven systems

Important issue in the perspective of nuclear energy development in the near future is the partitioning and transmutation (P&T) of spent nuclear fuel. For years the European Commission (EC) has sponsored this scientific activity through the Framework Programmes (FP). One of the milestones for P&T is the development of accelerator driven systems (ADS). Extensive research in this field was carried out within the EUROTRANS project of 6th FP of EURATOM. Part of this research was devoted to testing and development of reactivity monitoring techniques in ADS. This paper concerns the methods of the reactivity measurement using the pulsed neutron source (PNS). Due to the fact that basic methods devoted to determine the core reactivity are derived from point kinetics, while real subcritical core kinetics differs from this model, there is a need to improve these methods in order to deal with the observed spatial effects. There are several ways to make these methods work properly and finally it should be possible to achieve this. However, they still need a validation which is supposed to be done within next FP project FREYA

Assessment of the control rods shadow effect in the VENUS-F core

The partitioning and transmutation (P&T) of spent nuclear fuel is an important fi eld of present development of nuclear energy technologies. One of the possible ways to carry out the P&T process is to use the accelerator driven systems (ADS). This technology has been developed within the EURATOM Framework Programmes for several years now. Current research in this fi eld is carried out within the scope of 7th FP project FREYA. Important parts of the project are experiments performed in the GUINEVERE facility devoted to characterising the subcritical core kinetics and development of reactivity monitoring techniques. The present paper considers the effects of control rods use on the core reactivity. In order to carry out the evaluation of the experimental results, it is important to have detailed core characteristics at hand and to take into consideration the differences in the effect of control rods acting separately or together (the so-called shadow effect) on both the reactivity value and the measured neutron fl ux. Also any core asymmetry should be revealed. This goal was achieved by both MCNP simulations and the experimental results. However, in the case of experimental results, the need for calculating respective correction factors was unavoidable

Assessment of the control rods shadow effect in the VENUS-F core

The partitioning and transmutation (P&T) of spent nuclear fuel is an important fi eld of present development of nuclear energy technologies. One of the possible ways to carry out the P&T process is to use the accelerator driven systems (ADS). This technology has been developed within the EURATOM Framework Programmes for several years now. Current research in this fi eld is carried out within the scope of 7th FP project FREYA. Important parts of the project are experiments performed in the GUINEVERE facility devoted to characterising the subcritical core kinetics and development of reactivity monitoring techniques. The present paper considers the effects of control rods use on the core reactivity. In order to carry out the evaluation of the experimental results, it is important to have detailed core characteristics at hand and to take into consideration the differences in the effect of control rods acting separately or together (the so-called shadow effect) on both the reactivity value and the measured neutron fl ux. Also any core asymmetry should be revealed. This goal was achieved by both MCNP simulations and the experimental results. However, in the case of experimental results, the need for calculating respective correction factors was unavoidable