The effect of radiolysis on material degradation under sub and supercritical water conditions

Inadequate understanding of radiation-induced water chemistry under supercritical conditions has been identified as one of the important obstacles in the development of a supercritical water-cooled reactor. Radiolysis of supercritical water generates a variety of redox reactive species, but their persistence in supercritical water is not well understood. While there is limited experimental data, it is possible to develop a model for the radiolysis of supercritical water. This paper describes how a liquid-like radiolysis model (LLRM) and a vapour-like radiolysis model (VLRM) could assemble to predict steady-state concentrations of key reactive species and critically evaluate the available data. (author)