THTF/ORNL (SET facility)

Experimental details:

When steady state was reached. the lines from the pressurizer to the shroud annulus and the line from the annulus to the test section outlet were closed. thus isolating the shroud annulus from the rest of the system. After an additional period of stabilization. bundle power was trimmed to produce peak FRS temperatures of about 1033 K (1400°F) (maximum temperature imposed by safety limits). This produced the maximum number of uncovered levels for the subject pressure and mass flow rate. Once again. the loop was allowed to stabilize. after which a 20-s data scan was taken. Data were recorded at a rate of 10 points per second per instrument. Once data had been acquired. the pressure. flow. and power were slowly changed to the next test point. In general. it was possible to do this without recovering the bundle.