Inherent Control of Nuclear Propulsion Reactors

Recent developments in the control of nuclear propulsion reactors are discussed. Analog simulation studies of engine performance have emphasized: (1) the use of hydrogen propellant moderating qualities for reactor power control, instead of neutron absorption in the control drums, and (2) the use of reactor temperature as the power reference, instead of neutron density. The concept of inherent control based on these two factors results in a smoother control function and in a simple and reliable control system. +Senior Scientist, Douglas Aircraft Co., Santa Monica, California 90406.