SBIR-STTR Award

The combination of a magnetohydrodynamic (MHD) generator of the disk type with a (NERVA) reactor yields an advanced space power system with gigawatt pulse and megawatt continuous operating capability, at low specific mass and high specific enthalpy extraction. The novel aspect of this system is the disk MHD generator operating in the non-equilibrium mode with cesium seeded hydrogen as the working fluid. In this study, systems and engineering issues are being investigated in order to couple the generator to a NERVA hydrogen cooled reactor. The disk generator operating conditions required for an optimized system are being determined and models are being set up for the multi-component working fluid. Feasibility of non-equilibrium ionization in-hydrogen is being determined and conditions for stable plasma behavior are being identified. Design of engineering experiments to obtain data on plasma behavior and non-equilibrium disk generator operation are also being undertaken. The feasibility of operating a non-equilibrium MHD disk generator with hydrogen as the working fluid would be established from this assessment of the performance potential of the advanced multi-megawatt space power system comprising a disk MHD generator coupled to a NERVA reactor. Development of a disk generator could also result from a successful program for terrestrial MHD systems particularly central station electric utility applications.

HMJ Corp. will use the combination of a magnetohydrl dynamic generator of the disk type with a NERVA reactor yields an advanced space power system with the capability of producing up to gigawatt pulses and multi-megawatt continuous operating capability. Several features result from the combination of this type of reactor and a disk MHD generator in which hydrogen serves as the plasma working fluid. Cesium seeding is utilized under conditions which enable the generator to operate stable in the non-equilibrium electrical conduction mode. In common with all practical MHD generators, the side output is DC and voltages in the range 20-lOOkV are attainable. This leads to a simplification of the power conditioning system and a major reduction in specific mass. Taken together with the high performance capabilities of the NERVA reactor, the result is an attractively low overall system specific mass. Further, the use of non-equilibrium ionization enables high system specific enthalpy extraction's to be obtained, values in excess of 40% being attainable.