Year
2005
Abstract
A technical program at Sandia National Laboratories (SNL) sponsored by the Department of Energy (DOE), Office of Civilian Radioactive Waste Management, is underway concerning the survivability of spent nuclear fuel (SNF) transportation packages in tunnel fire environments. This program is analyzing several tunnel fire scenarios and casks in order to better understand this thermal environment and determine the severity of tunnel fires relative to the regulatory thermal requirements. The program will provide useful data and information for conducting routing analyses, for communication of the relative safety of SNF shipments to the public, and for first responders in the event of a tunnel fire by means of specific fire threat tables for particular tunnels. This paper summarizes preliminary results from a series of tunnel fire analyses performed to investigate the effects of tunnel design on the resulting thermal environment that a spent nuclear fuel transportation package positioned inside the tunnel would experience. The computational fluid dynamics fire code CAFE-3D was used to perform the analyses presented in this paper. Preliminary results show enhancement of heat transfer when the width of the tunnel was reduced; however, tunnel length did not have a strong effect on heat transfer.