CONTROL ELEMENT HEAT TRANSFER PARAMETER STUDY FOR SRE-PEP THIRD CORE

Technical Report · Sun Dec 01 04:00:00 EST 1963

OSTI ID:4068971

Johnson, C G; Schreiner, S I

Control rod allowable linear heat rates have been established at 14.4, 17.6, and 21.0 kw/ft for limiting pull tube inside surface temperatures of 1800, 1900, and 2000 deg F, respectively for an initial cold radial helium gap of 0.023inch. The predicted maximum heat rates are 12.26 kw/ft for 30 Mw(t) reactor operation and 16.35 kw/ft for 40 Mw(t) operation. The corresponding pull tube temperatures are 1717 and 1861 deg F, which are within the range of allowable temperatures. An hydraulic analysis of the control rod channel indicates that an annulus thickness of 0.364-inch will provide adequate cooling of the proposed 4 shim control rods to 40 Mw(t) operation or higher. This reflects an increase of 0.114-inch over the thickness of 0.250-inch for the annulus used in previous designs. For operation above 30 Mw(t), both the mixed-mean reactor outiet and core tankreflector annulus outlet sodium temperatures must be lowered by about 42 deg F. The control rod coolant outlet temperature is maintained at 1200 deg F or less under normal operation by controlling the core tank-reflector annulus outlet temperature which is required to be set at about 1132 deg F. The initial cold radial helium gap of 0.023-inch between the absorber and thimble decreases to about 0.021inch for normal operation. Proper movement of the control rod is therefore assured. The inner helium gap between absorber and pull tube of 0.1125- inch reduces to 0.110-inch under thermally expanded conditions. Because the heat generation rate in the pull tube is only about 5% of the total, there is littie incentive to change the inner helium gap size. (auth)

• Research Organization: Atomics International. Div. of North American Aviation, Inc., Canoga Park, Calif.
• DOE Contract Number: AT(11-1)-GEN-8
• NSA Number: NSA-18-015449
• OSTI ID: 4068971
• Report Number(s): NAA-SR-Memo-9281
• Country of Publication: United States
• Language: English

Related Subjects

ABSORPTION
CONFIGURATION
CONTROL ELEMENTS
COOLING
EXPANSION
HEAT TRANSFER
HEATING
HELIUM
HIGH TEMPERATURE
HYDRAULICS
MOTION
OPERATION
PLANNING
POWER
REACTOR CORE
REACTOR TECHNOLOGY
REACTORS
REFLECTORS
RODS
SODIUM
SURFACES
TEMPERATURE
THICKNESS
TUBES
VESSELS
ZONES