Semiscale Mod-1 program and system description for the blowdown heat transfer tests (test series 2)

Quarterly technical progress report on water reactor safety programs sponsored by the Nuclear Regulatory Commission's Division of Reactor Safety Research, October--December 1976

“…These measurements indicated gradual cladding collapse of 0.20 to 0.23 mm in the film boiling zones. 1 The calculated cladding surface temperatures for the three instrumented rods were in good agreement with the steady state measurements. The calculated fuel centerline temperatures were about 200 K higher than those measuretl at rut!…”

“…The specific objectives of Test GC 2-1 were to: ' . (1) Obtain experiment data for estimating gap conductance values by both the steady state (fkdt) and power oscillation experiment methods.…”

“…These data were compared with data f~om 141 data points obtained with the rod bundle without external thermocuupk simulators. Figure 24 with data in Figure 25 indicates that the ONB heat flux is higher for the bundle without thermocouple simulators than for the bundle with the simulators both at steady state and over the following operating ranges: (1) Pressures from 13.8' to 16.5 MPa (2) Mass velocities from 1360 to 3400 kg/s-m2…”

“…[a] 110 135 171 203 241 260 6.23 X 10-8 1. 0 ' X 10-7 ' -7 . 1.0 X 10 J. 36 X 10-7 ~.43 X 10-7 3.61 X 10-7…”

“…EXP*P4/CE code, an experim~e.ntal code very similar to RELAP4/MODS Update 2. 1 Intact loop pump differential pressure (Test S-05-2) · ; 4 3. Intact loop pump differential pressure (Test S-05-2A) 5 4.…”