The primary objective in this study is to develop a conservative and predictive tool for the criticality calculation applied to the dynamics of the continuous dissolver. The safety analysis for the dissolver usually performed through the combination of Monte Carlo methods and multigroup neutronic data processing system. But it is the main theme of this study that one can conservatively evaluate the criticality of the continuous dissolver using simple two-group diffusion theory and the corresponding neutronic data available.
From a safety point of view, much conservatism is allowed in the dissolver dynamic model, and the predicted $k_{eff}$ turned out to have sufficiently conservative values. The ODTG code, developed here using one-dimensional, two-group diffusion theory and a homogenized shell model, shows that the dissolver system is sufficiently subcritical under various operating conditions, even if abnormal condition occurs.
The ODTG code can be utilized as a conservative and valuable tool for the prediction of the nuclear criticality applied to the dynamics of the continuous dissolver system.