Measurement of Al2O3-B4C burnable poison core parameters por PWRs

Burnable poison rods, made of Al2O3-B4C pellets with 5.01 mg/cm310B concentration, have been manufactured for a set of experiments in the IPEN/MB-01 zero-power reactor. Several core parameters which are affected by the burnable poisons rods have been measured. The principal results, for the situation in which the burnable poison rods are located near the absorber rods of a control rod, are that they cause a 30 % rod worth shadowing, a reduction of 39 % in the local void coefficient of reactivity, a reduction of 5,0 % in the isothermal temperature coefficient of reactivity, and a reduction of 10 % in the thermal neutron flux in the region where the burnable poison rods are located. The calculated results obtained with the HAMMER/CITATION codes available in the IPEN/CTMSP produced very good comparisons with experimental results. (author)