Results of the Thermal-Shock Modeling and Analyses for the National Spallation Neutron Source

An overview is provided on preliminary observations from simulations of thermal shock in the National Spallation Neutron Source (NSNS) at various power levels. The simulation framework being utilized and under development is presented. Results of simulations for pressure and stress profiles at key locations are presented. Variation of results with possible onset of mercury cavitation were modeled and the results are discussed. Significant reductions in stresses on structures may be possible with cavitation onset. Key thermal-shock related issues are highlighted