CANDU--BLW EXPERIMENTS IN ZED-2. PART III. BUCKLING AND LOSS OF COOLANT EXPERIMENTS

Experiments have been performed in simulated CANDU-BLW lattices in ZED-2 (square arrays of 28-rod UO{sub 2} clusters at a spacing of 27.94 cm) to determine: (a) the material buckling of the lattice with H{sub 2}O or air as 'coolants'; and (b) the flux perturbation and reactivity effects of removing the H{sub 2}O coolant from 50% of the fuel assemblies in three geometric arrangements. The buckling for the H{sub 2}O-cooled lattice was 1.166 +- 0.018 m{sup -2} and for the air-cooled lattice 3.949 +- 0.039 m{sup -2}. The loss of coolant experiments indicated a significantly smaller increase in reactivity when alternate fuel assemblies or alternate rows of fuel assemblies were voided than when one-half of the lattice about a diameter was voided. (auth)