The first of these comprises the integral vessel failure experiments themselves. The tests are heavily instrumented to fully characterize the imposed boundary conditions as well as the vessel response. These instruments include numerous thermocouples, displacement transducers, and infrared video of the vessel bottom. Video is taken at normal speed, to visually record vessel displacement, as well as at high speed, to capture the propagation of the rupture at failure. Detailed digitized mapping of the pretest and post-test vessel surface and wall thickness also help characterize the overall vessel deformation.
Further information is derived from material testing.
Test samples were made from this extra vessel and standard engineering tensile and creep property tests were performed to construct a material constitutive law. The third key element is model development and validation. Data collected from the integral tests is then used in validating this model. Richard Simpson, a test engineer at Sandia National Laboratories, measures a weld seam inside a scale model of a lower-head assembly. Achieving such temperatures required Chu and the project engineer, John Bentz, to devise a new way to heat the vessel, using an inductive heater with a graphite cylinder to simulate a real meltdown.