Simulations of Single Pin Cell and CANDU

Abstract

The supercritical water reactor is one of six Generation IV reactor designs and is currently being studied by Canada. The use of supercritical light water as a coolant will provide many benefits due to plant simplifcations and improved thermal efficiency. Here, a model of a CANDU-SCWR lattice cell was simulated using two 2D neutron transport codes, WIMS and NEWT. Two lattice cell geometries are used in these simulations. The first is a single pin fuel cell, similar to that of a pressurized water reactor. The second is a 43-element CANFLEX geometry fuel bundle with a centre element containing a mixture of dysprosium oxide and natural uranium. A comparison between the two transport codes is made for the single pin cell while the effects of coolant density on reactivity are examined for different cases of fuel burnup for the CANDU-type lattice cell.