AHWR physics design validation: experiments in the critical facility

An Advanced Heavy Water Reactor (AHWR) project has been taken up in BARC, for large-scale commercial utilisation of thorium fuel cycle. The nuclear design of the lattice and core has been finalised. The design envisages the use of a novel 54-pin MOX cluster with different enrichment of 233U and Pu in Thoria fuel pins and dysprosium displacer rod at the centre. It is designed to have a negative void coefficient of reactivity. The evaluation of the lattice characteristics requires experimental validation to freeze the design and obtain regulatory clearance, before embarking on fuel fabrication. A multi-purpose Critical Facility (CF) has been designed and is in an advanced stage of construction. The salient features of the physics design of this CF are explained. The various experiments planned in this facility for the AHWR and other lattice concepts are summarised. The basic principles of some of the experiments are discussed. (author)