Dynamic simulation of the SLOWPOKE-3 nuclear heating reactor

Abstract

A 2 MWth nuclear reactor, called SLOWPOKE-3 (Safe LOW- POwer Critical Experiment), is being developed at the Chalk River Nuclear Laboratories (CRNL). This pool-type reactor is cooled by natural circulation and is designed to produce hot water for commercial space heating and perhaps generate some electricity. It is intended for remote locations where the costs of alternative forms of energy are high. A dynamic simulation of this reactor, without closed-loop con trol, was developed and implemented on a hybrid computer, using the basic equations of reactor kinetics and of conserva tion of mass, energy and momentum. The natural circulation of downcomer flow in the pool was simulated using a special filter, capable of modeling various flow conditions. The simula tion was then used to study the intermediate and long-term tran sient response of SLOWPOKE-3 to large disturbances, such as loss of heat sink, loss of regulation, daily load following, and over- cooling of the reactor coolant. Results of the simulation show that the reactor is inherently stable and self-regulating and that none of these disturbances produce hazardous transients.