Patent Number: 039869253
Section: summary

The present invention relates to the generation of electrical power by means of nuclear reactor and MHD-system using alkaline metal as working fluid. In the past, energy gained by nuclear reaction has been extracted from the reactor by heat exchange with a cooling fluid. The thermal energy extracted drives a steam power plant, which, in turn, drives an electric generator. These steam power plants are comprised of large multiple housing type steam turbines which drive the generator. Additional components included in such a conventional power plant are condensers and preheaters. Aside from multiple (lossy) energy conversion reducing the efficiency, these types of power plants are inherently large, and their particular operating characteristics render them unsuitable for the production of energy in space vehicles, such as space stations or the like. Another system for providing more efficient conversion of nuclear energy into electricity has been developed, particularly for space vehicles. These systems are known under the designation Magneto-Hydro-Dynamic System, or MHD for short. In such a system fluid is heated in a nuclear reactor, accelerated under pressure reduction and caused to flow across a magnetic field. An electric current can be drawn from the fluid along an axis perpendicular to both, the magnetic field and the stream of flowing fluid. Alkaline metals are used as working fluid, to provide for both, extraction of thermal energy from the nuclear reactor and pressure-to-kinetic-to-electric energy conversion in the MHD-system. The working fluid is employed in the liquid phase and in the gaseous phase. Particularly, when passing through the MHD-system, the fluid is in a fog-like state with liquid droplets carried by a vapor stream. The fluid receives thermal energy from the nuclear reactor operating as prime heat source and providing primarily vaporization. Fluid that enters the reactor is essentially liquidous. Gas bubbles may be created, in some cases, enlarge and merge upon heating. The enthalpy of the gaseous fluid component is subsequently converted into kinetic energy and that, in turn, serves to accelerate the liquid component that is carried along. Electrical energy is taken directly and primarily from the liquid phase as passing through a magnetic field within the MHD-generator. The MHD-system in accordance with the present invention is an improvement of nuclear MHD-system as they are known. The problem solved by the invention is to provide an economical energy production and conversion that is independent from location and, therefor, suitable for employment in any terrestrial environment. Power rating and power factor are to be subject to selection and control so as to establish a high degree of versatility and reliability of the plant. In accordance with the present invention it is suggested to organize a power plant as a whole in such a manner that plural, similarly constructed units are provided which operate electrically in parallel on a common electrical power bus. However, each unit includes its own independent MHD unit with an individual, closed loop for the working fluid as circulating through the MHD-generator and the nuclear reactor for heat exchange therein. Each unit shares in the nuclear reactor, and the portion of the reactor included in each unit is individually controllable as to the amount of its contribution in the production of thermal energy. However, the neutron flux penetrates the reactor as a whole. Air circulation is provided for particular heat-exchange coupling to each working fluid circulation loop, for removing therefrom residual thermal energy prior to recycling through the reactor. For example, a seawater desalination plant may be provided for using the thermal energy in the heated cooling air as discharged from all units. In this case, air flows in an open loop. However, a closed loop circulatory air system could be provided. Cooling air may circulate through each unit by operation of a compressor driven by a gas turbine that extracts thermal energy from the air. Each unit has its own compressor-turbine aggregate.