Fabian Jatuff

The recent experimental programme conducted in the PROTEUS research reactor at the Paul Scherrer Institute (PSI) has concerned detailed investigations of advanced light water reactor (LWR) fuels. More than fifteen different configurations of the multi-zone ...

Elsevier Science Ltd.2009

Impact of new gadolinium cross sections on reaction rate distributions in 10x10 BWR assemblies

Radial distributions of the total fission rate and the238U- capture-to-total-fission (C 8/F tot) ratio were measured in SVEA-96+ and SVEA-96 Optimal assemblies during the LWR-PROTEUS program. Fission rates predicted using MCNPX with JEFF-3.1 cross sections ...

American Nuclear Society2009

Determination of within-rod caesium and europium isotopic distributions in high burnup fuel rods through computerised gamma-ray emission tomography

Michaël Plaschy, Rakesh Chawla, Fabian Jatuff, Flavio Dante Giust

Computerised gamma-ray emission tomography has been applied to single PWR UO2 fuel rods, with pellet averaged burnups of 52, 71, 91 and 126 GWd/t respectively, for the determination of 134Cs, 137Cs and 154Eu internal radial distributions. State-of-the-art ...

Elsevier Science B.V.2009

Experimental validation of reaction rate distributions for a SVEA-96+ BWR assembly with hafnium control blades

The accurate estimation of reactor physics parameters related to the presence of cruciform absorber blades in boiling water reactors (BWRs) is important for safety assessment and for achieving flexible operation during the cycle. Characteristics that are a ...

Atomic Energy Society of Japan2009

Void reactivity coefficient benchmark results for a 10x10 BWR assembly in the full 0-100% void fraction range

Rakesh Chawla, Fabian Jatuff, Flavio Dante Giust

A boiling water reactor SVEA-96+ fresh fuel lattice has been used as the basis for a benchmark study of the void reactivity coefficient at assembly level in the full voidage range. Results have been obtained using the deterministic codes CASMO-4, HELIOS, P ...

Elsevier Science Ltd.2009

Comparison of optimised germanium gamma spectrometry and multicollector inductively coupled plasma mass spectrometry for the determination of 134Cs, 137Cs and 154Eu single ratios in highly burnt UO2

Non-destructive and destructive methods have been compared to validate their corresponding assessed accuracies in the measurement of 134Cs/137Cs and 154Eu/137Cs isotopic concentration ratios in four spent UO2 fuel samples with very high (52 and 71 GWd/t) a ...

Elsevier Science B.V.2008

Nondestructive determination of fresh and spent nuclear fuel rod density distributions through computerised gamma-ray transmission tomography

The morphology of single PWR UO2 fuel rods has been investigated by employing computerised gamma-ray transmission tomography. Four highly burnt fuel rods of different burnups (from 52 GWd/t to 126GWd/t) and a fresh rod have been investigated. This paper de ...

Atomic Energy Society of Japan2008

Comparison of 3D reaction rate distributions measured in an optima2 BWR assembly with MCNPX predictions

Rakesh Chawla, Fabian Jatuff, Filippo Tani

As part of a joint research programme between the Paul Scherrer Institute (PSI) and swissnuclear, with the co-operation of the Leibstadt nuclear power plant in Switzerland and fuel suppliers Westinghouse Sweden, measurements and calculations have been made ...

Elsevier Science Ltd.2008

Diagnostic analysis of pin-removal reactivity worth experiments in a SVEA-96+ test lattice

The present paper concerns a novel type of integral database generated in the course of the LWR-PROTEUS Phase I experiments, viz. the relative reactivity effects of removing individual fuel pins from a highly heterogeneous BWR assembly. The measurements re ...

Elsevier Science Ltd.2008

Characterisation of radial reaction rate distributions across the 92-pin section of a SVEA-96 Optima2 assembly

Characterisation of the SVEA-96 Optima2 boiling water reactor assembly, in terms of the radial distributions of normalised total fission and 238U capture rates, is reported at its central elevation, i.e. at the 92-pin section, where the one-third part-leng ...

Elsevier Science Ltd.2008

Investigations of238U captures to total fissions in a Westinghouse SVEA-96+ assembly

The reaction-rate ratio C8/Ftot, neutron captures in 238U to total fissions, has been measured in 80 out of 96 fuel rods of a Westinghouse SVEA-96+ boiling water reactor fuel assembly. High-resolution gamma spectroscopy was performed on individual fuel rod ...

American Nuclear Society2007

Radial and azimuthal 235U fission and 238U capture distributions in BWR UO2 pins: CASMO-4 and MCNP4C versus activation foil measurements

In the context of the LWR-PROTEUS program, radial and azimuthal 235U fission (F5) and 238U capture (C8) rate distributions have been calculated for zero-burnup pins of a Westinghouse SVEA-96 Optima2 boiling water reactor fuel assembly using the stochastic ...

ANS2007

Validation of 134Cs, 137Cs and 154Eu single ratios as burnup monitors for ultra-high burnup UO2 fuel

A measurement station has been built for the non-destructive investigation of burnt fuel rod segments through high-resolution gamma spectrometry. Four UO2 pressurised water reactor fuel rod segments with different burnup levels between 50 and 100GWd/t and ...

Elsevier2007

Optimised non-invasive method to determine 238U-captures-to-total-fissions in reactor fuel

High-resolution gamma spectroscopy was performed on individual fuel rods of a fresh, highly heterogeneous Boiling Water Reactor (BWR) fuel assembly, after irradiation at low power in the PROTEUS reactor at PSI, to determine the ratio of neutron captures in ...

Elsevier2006

Reactivity and neutron emission measurements of highly burnt PWR fuel rod samples

Michaël Plaschy, Rakesh Chawla, Fabian Jatuff, Filippo Tani, Flavio Dante Giust

Fuel rods with burnup values beyond 50GWd/t are characterised by relatively large amounts of fission products and a high abundance of major and minor actinides. Of particular interest is the change in the reactivity of the fuel as a function of burnup and ...

Elsevier2006

Comparisons of deterministic neutronic calculations with Monte Carlo results for an advanced BWR fuel assembly with hafnium control blades

From the neutronic viewpoint, the optimization of BWR core designs is strongly related to the accurate determination of flux variations inside and around fuel assemblies. These fluctuations, which are mainly due to the high heterogeneity of the fuel and mo ...

Atomic Energy Society of Japan2006

On the accuracy of reactor physics calculations for square HPLWR fuel assemblies