Visco-Plastic Flow Predictions of Solidified Deuterium-Tritium Mixtures

Visco-plastic flow properties of hydrogenic solids are important considerations for the design and operation of continuous hydrogenic pellet extrusion systems. Prior to 2010, the visco-plastic flow behavior of deuterium, tritium, and mixtures of the isotopes was only known at 14 K and no heat transfer studies were available. To address these needs, a Cryogenic Couette Viscometer (CCV) was developed at the University of Wisconsin-Madison. Visco-plastic flow characteristics of solid neon, deuterium, and hydrogen were measured using the CCV from the onset of solidification to sub-cooled solid states over a range of shear rates. This paper discusses the transformation of these measurements, using the Quantum Law of Corresponding States, to predict the visco-plastic flow behavior of solid tritium and deuterium-tritium mixtures. Comparisons of predicted values with experimental measurements are made, where available.