Abstract
The capability of a finite-element computer code STRAW to predict the structural response of LMFBR core subassembly hexagonal wrappers to postulated accidentical local energy releases has been verified by comparisons with test data from out-of-pile experiments. The code was applied to the analysis of the dynamic response of hexcans subjected to internal pressure pulse loadings, and the computational results were correlated with data from a series of tests on individual hexcan sections. The pressure was generated by a PETN burning mixture. Two specified pressure pulse shapes were generated to simulate hypothetical conditions created by a fuel-coolant interaction resulting from a fuel pin failure. The hexcan dynamic deflections were measured with light-emitting diode (LED) gauges, and the midflat circumferential and axial strains were measured with foil strain gauges. The sensitivity of the response to variations in both the pressure loading and the material properties of the stainless steel were examined. The ductility of the steel was varied by coldworking and annealing. Very low ductility test hexcan specimens were fabricated by coldworking introduced in the drawing process by means of a specially designed set of dies. High ductility specimens were produced by a solution annealing process. Sensitivity computations demonstrated that the hexcan response is determined not only by the peak value of the pressure pulse, but is also strongly influenced by the risetime. The dynamic response is also strongly influenced by the material properties of the steel. For example, under similar loading conditions the peak deflection for a low ductility hexcan was reduced by a factor of 8 compared with the deflection for an annealed hexcan. Conversely, it was found that the dynamic response, in turn, influences the material properties through strain-rate effects. Separate tensile tests were required to determine the influence of strain rates upon the stress-strain properties of the steel.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.