Modifications to SAS4 to provide cask dose rate profiles

Journal Article · Mon Dec 01 04:00:00 EST 1997 · Transactions of the American Nuclear Society

OSTI ID:552560

Napolitano, D G; Sweezy, J E ^[1]; Henkel, C S ^[2]

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1. NAC International, Norcross, GA (United States)
2. Henkel Technical Computing, Norcross, GA (United States)

SAS4 of the SCALE code system has been used extensively by NAC International (NAC) to perform storage and transport cask shielding analyses. SAS4 utilizes a one-dimensional XSDRNPM adjoint calculation of the cask to generate biasing parameters for a three-dimensional MORSE-SGC Monte Carlo model of the cask geometry. This technique is very efficient in getting particles to tally at the cask exterior surfaces. However, SAS4/MORSE-SGC is limited to the use of point detectors (next-event estimators) and large surface detectors (surface-crossing estimators). Modifications to SAS4 were made to allow a more flexible use of the surface detectors. This modification allows multiple nonoverlapping surface detectors on each surface and allows each surface detector to be broken into subdetectors. The use of subdetectors enables the user to obtain detailed surface dose rate profiles. Tallies can now be performed on all surfaces of the cask and at user-specified distances from the cask surface. The subdetectors provide an alternative to point detectors and excessive computational time. The NAC version of SAS4 is called SAS4A. A comparison of CPU time and dose rates is made between SAS4 point detectors and SAS4A surface subdetection on the NLI {1/2} transport cask.

• OSTI ID: 552560
• Report Number(s): CONF-971125--
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Vol. 77; ISSN 0003-018X; ISSN TANSAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DOSE RATES
RADIATION TRANSPORT
S CODES
SHIELDING
SPENT FUEL CASKS