ANALYSIS OF ASTR MELTDOWN CONFIGURATIONS.
Abstract
Potential fuel configuration from core meltdown of the Aerospace Systems Test Reactor (ASTR) have been analyzed to determine whether criticality is possible when water re-enters the core after melt solidification. The initial calculations, however, were made for the normal ASTR configuration with and without control rods as a check on the cross-section input data. A 1% decrease in the thermal-neutron absorption cross section of the core material provided the desired eigenvalue without control rods. An empirical scaling factor for the absorption cross section of each cell region containing a control rod was determined to be 0.105. The configuration resulting from an ASTR core meltdown in the horizontal mode of operation may be critical under certain restrictive conditions, such as a uniform porous melt containing all of the fuel; in this case, the multiplication constant is 1.066 for an H-to-U235 ratio of 500. If the meltdown occurs in the forward-end-up mode of operation, the multiplication constant is 1.066 for an H-to-U235 ratio of 500. Additional calculations resulted in a prompt-neutron lifetime of 0.000062 sec for the normal ASTR configuration and an effective delayed-neutron fraction of 0.0076 for the Ground Test Reactor (GTR). (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1966
- Accession Number
- AD0488450
Entities
People
- J. W. Mcwhirter
Organizations
- General Dynamics