Definition and Analysis of an Experimental Benchmark on Shutdown Rod Worths in LEU-HTR Configurations

HTR-PROTEUS pebble bed experimental program cores 9 & 10: columnar hexagonal point-on-point packing with a 1:1 moderator-to-fuel pebble ratio

“…These rods were separated into two groups of four rods (rods 1-4 and rods [5][6][7][8]. One of these groups was selected as the "safety rod" group and the other as the "shutdown rod" group.…”

“…The dimensions and specific linear densities of the various polyethylene rods are shown in Figure 1. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Most of the rods were either unmachined, or machined down to the reported diameter from a larger diameter rod.…”

“…CRIT-REAC The safety ring was comprised of Peraluman-300 (Table 1. [1][2][3][4][5][6][7][8] and had a total mass of 10.42 kg (Ref.…”

“…Some borated steel sections were analyzed separately at PSI on January 8, 1992 (see Table 1. [1][2][3][4][5][6][7][8][9]. The borated steel density was measured on December 17, 1993, using three as-built pieces; the density was 7.199 ± 0.029 g/cc.…”

“…Measured shutdown rod worths for Core 9 are in Table 1.4-12 and Core 10 in Table 1. [4][5][6][7][8][9][10][11][12][13].…”