Discussion on the stability of natural circulation loops with supercritical pressure fluids

► Analysis by a system code of natural circulation stability in an experimental loop containing water at supercritical pressure. ► Investigation of the basic features of the phenomenon. ► Dimensionless parameters to be used in an idealized case are assessed by the results of a system code are proposed. ► The analyses of the idealized loop and of the real one provide information on different important effects related to stability.