Abstract :
The control and instrumentation of nuclear reactors is a rapidly developing subject which is becoming of ever-increasing importance to a growing body of instrument engineers. Many of the problems of instrumental design are common with other industrial plants and follow conventional lines. Some, however, are more specialized, and arise principally from the radioactive nature of the reactor and its unusual dynamic behaviour. The paper presents a survey of the overall instrumentation of a typical research reactor. Emphasis is placed on the less-well-known problems of measurement and control, and to assist in their understanding a brief account is given of the mode of operation of a nuclear reactor, and a short Section on reactor kinetics is also included. The types of instruments in present-day use are described, and indications are given of their shortcomings. New developments are briefly reviewed. The paper concludes with a Section on reactor safety. The philosophy of safety-circuit design is outlined, and examples are given of instruments and circuits which conform to this basic code and which have been used on a number of experimental reactors at Harwell.
