DESIGN OF THE YANKEE CORE I FUEL ASSEMBLY

Technical Report · Fri Jan 01 04:00:00 EST 1960

OSTI ID:4164175

Thorp, II, A G

The mechanical, thermal, and hydraulic design characteristics of the Yankee Core I fuel assembly were established in detail. The core is made up of 23,142 fuel rods of full core length (7.5 feet) arranged to form 76 fuel assemblies. The fuel assemblies are of two types, 38 of each type being required for the complete core. The fuel assembly design was based upon the use of stainless steel cladding and UO/sub 2/ fuel. The basic objective of minimizing poison material in the core was achieved by the means of utilizing the fuel clad as the basic structural element of the fuel assemblies. Brazed ferrules and welded straps were considered as alternatives for joining the fuel rods into sub- assemblies, the final choice being the brazed ferrule construction which provides better thermal, hydraulic, nuclear and mechanical characteristics. Tests were conducted to verify the hydraulic characteristics of the fuel assemblies. Good correlation was found between the basic hydraulic parameters and the pressure drop. Metallurgical, mechanical, and process development testing was conducted on the fuel rod. Material properties were established and suitable design and process techniques were evolved for the fuel rods. An extensive development program to perfect brazing techniques was conducted to braze the fuel rods into sub-assemblies. The successful results of this program permitted the use of the brazed ferrule feature in the structural design of the fuel assembly. Thermal bowing tests were conducted on a single sub-assembly in order to verify analytical techniques. The resultant verification permitted the development of a final design which can be relied upon not to bow excessively during reactor operation. Other less critical components of the assembly were also subjected to mechanical tests. (auth)

• Research Organization: Westinghouse Electric Corp. Atomic Power Dept., Pittsburgh
• NSA Number: NSA-14-016471
• OSTI ID: 4164175
• Report Number(s): YAEC-154
• Country of Publication: United States
• Language: English

Related Subjects

BRAZING
CONFIGURATION
DEFORMATION
FUEL CANS
FUEL ELEMENTS
HYDRAULICS
MECHANICAL PROPERTIES
MECHANICAL STRUCTURES
METALLURGY
PLANNING
POWER PLANTS
REACTOR CORE
REACTOR TECHNOLOGY
REACTORS
STAINLESS STEELS
TESTING
URANIUM DIOXIDE
WATER COOLANT
WATER MODERATOR
WELDING
YAEC
YANKEE