Prediction of thermal consequences of plenum fission gas release in an LMFBR fuel assembly

One of the types of hypothetical accidents important in the safety analysis of Liquid Metal Fast Breeder Reactors is that in which fission gas release is postulated to occur from the plena of fuel pins at such a rate that significant perturbation to coolant flow occurs. Past consideration of such events has employed highly conservative calculations in the interest of simplicity and expediency. This paper describes a method developed to predict more accurately the thermal consequences of such fission gas release events.