Comparisons of calculated and measured parameters for a Pu-fueled LWHCR lattice

The lack of suitable integral experiments for Pu-fueled LWHCR lattices renders it difficult to assess the adequacy of calculational methods and data being applied to the physics design of such reactors. The current paper presents results for the first of a series of Cores being investigated in the PROTEUS reactor at Wuerenlingen to help fill the gap - a PuO2/UO2 fueled test lattice with an effective Pu enrichment of 7% and a fuel/moderator ratio of 2.0. The measurements reported include core-centre reaction rate ratios involving the capture rate in 238U and fission rates in 235U, 238U, 239Pu and 241Pu. Infinite-dilution reaction rates in the lattice were determined for the 10B(n,α) reaction and for 232Th, 233U fission. Also measured were various radial and axial reaction rate traverses across the test zone to provide material-buckling, and hence k/sub infinity/, related data. Comparisons of the measured parameters have been made with calculations based on the use of several different lattice codes and their associated cross-section libraries, viz. WIMS-D, EPRI-CPM and BOXER