Experiment data report for Semiscale Mod-1 Test S-05-2 (alternate ECC injection test)

Abstract

Recorded test data are presented for Test S-05-2 of the Semiscale Mod-I alternate emergency core coolant (ECC) injection test series. This test is one of several Semiscale Mod-I experiments conducted to investigate the the_rmal and hydraulic phenomena accompanying a hypothesized Joss-of-coolant' accident in a pressurized water reactor (PWR) system. Test S-05-2 was conducted from an initial cold leg fluid t~mperature of 545°F and an initial pressure of 2263 psia. A simulated double-ended offset shear cold leg break was used to investigate core and system response to a depressurization and reflood transient with. ECC injection at the intact loop pump suction and broken loop cold leg. A reduced lower plenum volume was used for this test to more accurately represent the lower plenum of a PWR, based on system volume scaling. System flow was set to achieve a core fluid temperature differential of 65°F at a core power level of 1.44 MW. The flow resistance of the intact loop was based on core area scaling. An electrically heated core with a slightly peaked radial power profile was used in the pressure vessel to simulate the predicted surface heat flux of nuclear fuel rods during a loss-of-coolant accident. The purpose of this report is to make available the uninterpreted data from Test s-05-2 for future data analysis and test results reporting activities. The dat::t, presented in the form of graphs ih engineering units, have been analyzed only to the extent necessary to assure that they are reasonable and consistent.

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

“…A probability of failure is calculated for each mode, and these probabilities are then appropriately combined to yield a general probability of failure of the fuel rod cladding. The cladding failure models that are curr~ntly operable in FRAIL include: (1) Cladding melt (2) Oxide lnycr wnll thinning (3) 'Ballooning (without rupture) (4) Eutectic ine1t (5) Collapse (6) Overstress failure (7) Cumulative stress damage (8) Overstrain failure.…”