XYLENE POWER LTD.

FNR MONITORING SYSTEM

By Charles Rhodes, P.Eng., Ph.D.

INTRODUCTION:
Elsewhere on this website Fast Neutron Reactors (FNRs) have been identified as the primary source of energy for meeting mankind's future energy needs. This web page focuses on the design of the FNR's monitoring system.
 

MONITORING SYSTEM OVERVIEW:
The monitoring system is ceiling mounted above the reactor space and looks down toward the top surface of the primary liquid sodium pool. The monitoring system is concerned with the central 12 m diameter of the liquid sodium surface which is directly over the FNR core zone. The monitoring system:
a) Uses a visible light laser scanner to monitor the vertical positions of each of 464 movable fuel bundles via the tube top hats;
b) Uses a gamma ray scanner to monitor the gamma ray emission from each of 464 indicator tubes;
c) Uses an infrared scanner to monitor the liquid sodium discharge temperature of each of the 464 indicator tubes.

A gamma flux output significantly above the full power level must immediately trip the reactor shutdown systems. Note that the gamma flux should be roughly proportional to the reactor's thermal load.

A local temperature significantly above the reactor setpoint must cause a slight withdrawal of the corresponding moveable fuel bundle. Note that the coolant surface temperature should be almost independent of the reactor's thermal load.

This web page last updated January 30, 2023.