BALL TYPE SAFETY ROD HEAT TRANSFER STUDY

Technical Report · Wed Mar 10 04:00:00 EST 1954

OSTI ID:4221046

Sletten, H L

From the standpo)int of the effects of temperature in boron-steel balls on the successful operation of the Ball Type Safely Device, there appeared to be three conditions which may be critical. (1) heat generation and temperature reached by this first falling ball, (2) temperature of the balls in their static position in the hopper above the reflector, and (3) the temperature of balls that may remain at the bottom of the thimble after rrcovery. These three situations are studied for the Sodium Reactor Experiment, P-16, in which 1/8 inch diameter 2 per cent by weight boron in steel is considered. It is found that the temperature of a first ball will increase not more than 8 deg F as it passes through nitrogen in the core at rated power. The temperature of the balls in the hopper will be about 120 deg F above the temperature of a 1000 deg F hopper wall. A ball at the bottom of the timble which is bathed by 500 deg F sodium at the core-reflector interface will have a temperature less than 1010 deg F. Appendix I includes an extended heat transfer analysis of a ball falling through a reactor core for a situation in which the heat capacity of the ball is small and assumed to be negligible in comparison to the heat which is liberated from the ball by convection and radiation. It is not applicable to P-16 unless one or more or the specific conditions of neutron flux, ball transient time in the core, length of reactor, and boron concentration are mereased so that the total effect is to increase the integrated heat generation by a factor of 10 or more. (auth)

• Research Organization: North American Aviation, Inc., Downey, Calif.
• NSA Number: NSA-13-019727
• OSTI ID: 4221046
• Report Number(s): NAA-SR-Memo-920
• Country of Publication: United States
• Language: English

Related Subjects

BORON-- CONVECTION-- HEAT TRANSFER-- PELLETS- - POWER PLANTS-- REACTOR SAFETY-- REACTORS-- SAFETY-- SPECIFIC HEAT-- STEELS-- THERMAL RADIATION-- VELOCITY in
BORON-- HEAT TRANSFER-- HEATING-- PELLETS-- POWER PLANTS-- REACTOR SAFETY-- REACTORS-- SAFETY-- STEELS-- TEMPERATURE
BORON-- HEAT TRANSFER-- LIQUID METAL COOLANT-- PELLETS-- POWER PLANTS-- REACTOR SAFETY-- REACTORS-- SAFETY-- SODIUM-- STEELS
REACTORS