Kernreaktoranlage mit organischem Kuehlmittel und Moderator

822,163. Nuclear reactors. NORTH AMERICAN AVIATION Inc. Oct. 2, 1956 [May 23, 1956], No. 29974/56. Drawings to Specification. Class 39(4). In a nuclear reactor, a single organic liquid, for example terphenyl, is used as the moderant, coolant and reflector. The enriched uranium, plutonium or thorium fuel rods are mounted vertically inside two concentric steel thermal shields which are surrounded by a steel gamma ray shield having a further thermal insulating lining. The control and safety elements consist of steel plates, coated with boron carbide and aluminium, and are moved horizontally through the core by a hydraulic system. The control system is adjusted automatically by a neutron level monitor. The fuel elements consist of long, thin, plates, clad in stainless steel or zirconium, and are mounted, in boxes of aluminium, steel or zirconium, so that the concentration of elements is highest at the core centre, to produce a uniform thermal flux. A single access opening in the upper surface of the shield permits servicing of all the fuel elements ; the opening is formed in a disc rotatable within a second rotatable disc, the disc axes being spaced apart. The coolant is first pumped upwards between the gamma-ray shield and the outer thermal shield and then down between the outer and inner thermal shields to a chamber at the base of the reactor from which it flows upwards, through the core to the outlet. The coolant decomposition products are burned after removal of the radioactive components.