NUCLEAR ANALYSIS OF THE MH-1A REACTOR

The conceptual design of the MH-1A reactor was analyzed using machine codes and methods previously shown to give good agreement with experimental measurements for a similar core. The cold clean reactivity worths of all 12 control rods and of the most important control rod were calculated to be DELTA k = 0.20 and DELTA k = 0.035, respectively. This indicates that the reactor can be adequately shut down with one rod stuck in the fully-withdrawn position. A radial peak-to-average power ratio of 1.63 was calculated for the case with followers in the core. The reactivity lifetime of the core was calculated to be 11 months for the initial core. Additional calculations showed that the first fuel shuffling'' gave a core with the same lifetime. (auth)