In control systems design for nuclear facilities, the correct choice for sensors, transducers and actuators is not an easy task when different options must be evaluated. In particular, for a Once Through Steam Generator (OTSG), the control of its boiling flow dynamics is usually performed with sensors that may be slow in response, must be placed all through the zone of interest (or need heavy mechanical modifications) and may not distinguish correctly when the liquid/steam interface is not so well defined at high temperatures and pressures. In this paper, a theoretical study about a reflectometric technique applied to an OTSG is proposed. This technique can be used also for the liquid/steam levels monitoring of the boiling flow. The overall behaviour of the variables of interest and the first theoretical results show the benefits of such an innovative approach.
