EFFECT OF APPR-1 CONTROL ROD ACCELERATION AFTER SCRAM ON STARTUP ACCIDENT

Technical Report · Tue Apr 23 04:00:00 EST 1957

DOI:https://doi.org/10.2172/4351381· OSTI ID:4351381

Gallagher, J. G.; Silks, T. M.

In the preoperational checkout of the APPR-1 it became apparent that the control rod acceleration after scram was lower than expected. It was expected that the control rod acceleration after scram would be 0.750 g(1) where g is the acceleration of gravity. However, measurements made at Ft. Belvoir indicated an acceleration of 0.4 g. The effect of this reduced acceleration on the safety of the APPR1 is reported in this memo. In the operation of the APPR1 the most dangerous condition exists at cold startup. Therefore the behavior of the APPR-1 in a startup accident with a rod acceleration of 0.4 g after scram is considered. Analysis of the most adverse startup accident in the APPR-1 indicated that at the 15 Mw level scram the reactor is on a 33 ms. period. Rod insertion begins after a 50 ms. instrument delay, at which time the power is 80 Mw. The maximum power reached with a rod acceleration of 0.4 g is 96.5 Mw. The total energy released is about 5.8 a 10/sup 3/ Btu which is far below the 8 x 10/sup 4/ Btu which would result in melting at the center line of the fuel element (and probable core destruction). If the rod acceleration were 0.759 g the maximum power would be between 80 and 90 Mw so that the reduced acceleration does not constitute any significant increase in energy release on a starting accident. (auth)

• Research Organization: Alco Products, Inc., Schenectady, N.Y.
• NSA Number: NSA-12-008052
• OSTI ID: 4351381
• Report Number(s): APAE-Memo-97
• Country of Publication: United States
• Language: English

Related Subjects

ACCIDENTS
CONTROL ELEMENTS
FAILURES
FUEL ELEMENTS
INSTRUMENTS
MELTING
OPERATION
PHYSICS
POWER
REACTOR CORE
REACTORS
RODS
SAFETY
SHUTDOWN
SM-1
STARTUP
VELOCITY