Eugene P. Wigner - Patents - 1956 through 1957

US 2,736,696 REACTOR – Wigner, E. P. et al; Feb 28, 1956 (to the U.S. Atomic Energy Commission)

A solid fueled, liquid moderated and liquid cooled slow neutron reactor is discussed. The solid fissionable material is natural U metal; the liquid moderator may be heavy; and the liquid coolant may be H₂O, biphenyl, or the like. The design provides for preventing losses of the fluid moderator due to leakage or contamination of the same by the liquid coolant. The reactor is characterized by good temperature stabilization at high neutron densities for extended periods of time, and provision for ready removal and replacement of the fissionable fuel when desired. The neutronic system includes an effective emergency control for reducing the reactivity, as well as automatic means for continuing proper cooling of the active fissionable material in the event of failure of the principal cooling system. (auth)

US 2,743,225 REACTOR – Wigner, E. P.; Weinberg, A. M.; Young, G. J.; Ohlinger, L. A.; Apr 24, 1956 (to the U.S. Atomic Energy Commission)

A solid-fuel heavy-water-moderated reactor is described. The fuel is in the form of rods or slugs and the moderator is pressurized to prevent boiling in order to maintain a relatively high density and minimize the critical size of the reactor. Provision is made for the rapid evacuation of the D₂O moderator, thereby stopping the chain reaction in the event of an emergency. A thin walled A1 vessel housing the core containing the fuel elements is surrounded by a neutron reflector of graphite and He under pressure within a heavy outer shell to equalize the force on the inner walls of the vessel. This design results in a compact relatively safe reactor making economical use of the expensive materials contained therein. (auth)

US 2,770,591 HEAVY WATER MODERATED NEUTRONIC REACTOR – Wigner, E. P. et al; Nov 13, 1956 (to the U.S. Atomic Energy Commission)

The design of the basic light water cooled,, heavy water moderated natural uranium reactor designed to operate at high power levels for an extended period of time to produce plutonium is presented. The uranium, in sealed containers, is positioned in aluminum tubes, through which light water flows to maintain a temperature below the melting point of the various materials. Heavy water surrounds the tubes in the reactor core to slow the neutrons, produced by fission, to the energy level necessary for maintenance of the chain reaction and the conversion of uranium 238 by neutron capture to plutonium. Heavy water is found to be a superior moderator to graphite in requiring less volume and capturing less neutrons. This reactor is designed to operate at a power output of 50,000 kilowatts. (auth)

US 2,781,307 APPARATUS FOR THE MEASUREMENT OF NEUTRON ABSORPTION – Wigner, E. P.; Feb 12, 1957 (to the U.S. Atomic Energy Commission)

An apparatus designed to measure the unknown neutron absorptive properties of a substance is described. This accomplished by the cyclic insertion and removal of the sample substance from a reactor core. The power level of the reactor varies with the same frequency as the positioning of the sample relative to the core. The fluctuation of the power level can be measured by suitable means such as an ionization chamber, which is then compared with the fluctuation caused by the positioning of a sample with known neutron absorptive properties, and a comparison or relative measurement of the unknown properties may be determined. (auth)

US 2,806,820 NEUTRONIC REACTOR – Wigner, E. P.; Sep 17, 1957 (to the U.S. Atomic Energy Commission)

A reactor of the type having coolant liquid circulated through clad fuel elements geometrically arranged in a solid moderator, such as graphite, is described. The core is enclosed in a pressure vessel and suitable shielding, wherein means is provided for circulating vapor through the core to superheat the same. This is accomplished by drawing off the liquid which has been heated in the core due to the fission of the fuel, passing it to a nozzle within a chamber where it flashes into a vapor, and then passing the vapor through separate tubes extending through the moderator to pick up more heat developed in the core due to the fission of the fuel, thereby producing superheated vapor.

US 2,810,689 FLUID MODERATED REACTOR – Wigner, E. P.; Ohlinger, L. A.; Young, G. J.; Weinberg, A. M.; Oct 22, 1957 (to the U.S. Atomic Energy Commission)

A reactor which utilizes fissionable fuel elements in rod form immersed in a moderator or heavy water and a means of circulating the heavy water so that it may also function as a coolant to remove the heat generated by the fission of the fuel are described. In this design, the clad fuel elements are held in vertical tubes immersed in heavy water in a tank. The water is circulated in a closed system by entering near the tops of the tubes, passing downward through the tubes over the fuel elements and out into the tank, where it is drawn off at the bottom, passed through heat exchangers to give up its heat and then returned to the tops of the tubes for recirculation.

US 2,815,321 ISOTOPE CONVERSION DEVICE – Wigner, E. P.; Young, G. J.; Ohlinger, L. A.; Dec 3, 1957 (to the U.S. Atomic Energy Commission)

This patent relates to nuclear reactors of the type utilizing a liquid fuel and designed to convert a non-thermally fissionable isotope to a thermally fissionable isotope by neutron absorption. A tank containing a reactive composition of a thermally fissionable isotope dispersed in a liquid moderator is disposed within an outer tank containing a slurry of a non-thermally fissionable isotope convertible to a thermally fissionable isotope by neutron absorption. A control rod is used to control the chain reaction in the reactive composition and means are provided for circulating and cooling the reactive composition and slurry in separate circuits.