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Results of Hydrogen-Uranizim Plasma Composition Calculations

        The HUPLAZ-2 program was used to calculate the hydrogen-uranium plasma composition in the coolant-fuel mixing region. The composition was calculated for pressures from 1 atm to 1000 atm and temperatures from 50001K to 120,0001K. Typical results are shown in Figure 15 for a pressure of 500 atm and a mixing ratio of 1.0. The relative densities of the uranium species are similar'to those of the unmixed uranium plasma shown in Figure 9. The relative hydrogen densities are similar to the unmixed hydrogen plasma densities shown in Figure 13. The electron density in the mixed plasma is seen to be characteristic of the uranium species rather than the hydrogen species. This is to be expected since uranium species from one to twelve times ionized are considered, while the ionized hydrogen includes only the singly ionized species H+ and H2. Thus, in a mixed plasma having similar hydrogen and uranium densities, the total pressure for temperatures above 30,000'K is primarily due to electrons. The mixing ratio used in a hydrogen-uranium plasma composition calculation is determined by the simulated mixing described in Chapter VII.