THE CONTROL RODS OF THE WINDSCALE PILES AND THEIR ADEQUACY FOR FUTURE OPERATING CONDITIONS

Technical Report · Thu Oct 01 04:00:00 EST 1953

OSTI ID:4282768

Gallie, R R; Smart, E

The direct calibration of the control rods was extended from 138 to 30 cm from pile center. During the experiments, it was found that tae pile k released by discharging flattening channels was dependent on their position in the pile. This effect is due to the fact that the normal operational flux distribution is modified when the control rods are in the pile. It was deduced from the experimental results that for the fully enriched pile, the pile k taken up by the flattening under shut-down conditions will be 0.2 to 0.3% less than under operating conditions. Estimates of the control required under shutdown conditions, allowing for this change in pile k taken up by flattening and assuming safety factor of 0.5% in k, show that further control of from 0.2 to 0.3% is required. It is recommended that this extra k be obtained by fitting longer extension pieces to the control rods so that they can run in to pile center and loading extra absorbers in the pile on shutdow. (auth)

• Research Organization: Gt. Brit. Windscale Works, Sellafield, Cumb., England
• NSA Number: NSA-13-010639
• OSTI ID: 4282768
• Report Number(s): RDB(W)/TN-108; WTSC/R-100
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
BPP-1
BPP-2
CONTROL
CONTROL ELEMENTS
CONTROL SYSTEMS
DISTRIBUTION
ENRICHMENT
FUEL ELEMENTS
LEVELS
MEASURED VALUES
MULTIPLICATION FACTORS
NEUTRON FLUX
NUMERICALS
OPERATION
REACTIVITY
REACTOR FUELING
REACTOR SAFETY
REACTORS
RODS
SHUTDOWN