Bare U(93)C$sub 170$ assembly [report]

J.C. Hoogterp, G.E. Hansen, H.C. Paxton
1974 unpublished
The "Honeycomb" critical assembly considered here is a nominal cube of UO3.15) foil and graphite plates regularly interleaved such that the carbon-to-uranium atomic ratio is 170. The assembly description is corrected empirically to a homogeneous near-cube reflected only by a low-density aluminum matrix that extends through th« core and to the outside. Critical specifications for checking calculations are given in x, y, z coordinates and in equivalent r, z coordinates. Other quantities useful as
more » ... computational checkpoints are spectral indexes, typified by ff i (U-235)/5j(U-238)= 110, and central reactivity contributions of foil samples at various thicknesses. Effective reactivity coefficients of 2°B U, thorium, tungsten, and molybdenum change significantly with sample thickness, whereas the reactivity coefficient of 23i U is essentially constant at 9.4 c/g-atom for thicknessas up to 0.028 cm.
doi:10.2172/4288188 fatcat:dg7djmhnkbe5za5ooxvv2fza4u