Publications

Rao, Rekha R.; O'Hern, Timothy J.; Domino, Stefan P.; Wyatt, Nicholas B.; Tikare, Veena T.; Erickson, Lindsay C.; Shelden, Bion S.; Brotherton, Christopher M.; Cipiti, Benjamin B.; Pawlowski, Roger P.; Noble, David R.; Jove Colon, Carlos F.; Moffat, Harry K.; Roberts, Christine C.; Nemer, Martin N.

Abstract not provided.

Rao, Rekha R.; Pawlowski, Roger P.; Brotherton, Christopher M.; Cipiti, Benjamin B.; Domino, Stefan P.; Jove Colon, Carlos F.; Moffat, Harry K.; Nemer, Martin N.; Noble, David R.; O'Hern, Timothy J.

Imported oil exacerabates our trade deficit and funds anti-American regimes. Nuclear Energy (NE) is a demonstrated technology with high efficiency. NE's two biggest political detriments are possible accidents and nuclear waste disposal. For NE policy, proliferation is the biggest obstacle. Nuclear waste can be reduced through reprocessing, where fuel rods are separated into various streams, some of which can be reused in reactors. Current process developed in the 1950s is dirty and expensive, U/Pu separation is the most critical. Fuel rods are sheared and dissolved in acid to extract fissile material in a centrifugal contactor. Plants have many contacts in series with other separations. We have taken a science and simulation-based approach to develop a modern reprocessing plant. Models of reprocessing plants are needed to support nuclear materials accountancy, nonproliferation, plant design, and plant scale-up.

Rao, Rekha R.; Noble, David R.; Schunk, Randy; Wilkes, Edward D.; Baer, Thomas A.; Rao, Rekha R.; Notz, Patrick N.

Solidification and blood flow seemingly have little in common, but each involves a fluid in contact with a deformable solid. In these systems, the solid-fluid interface moves as the solid advects and deforms, often traversing the entire domain of interest. Currently, these problems cannot be simulated without innumerable expensive remeshing steps, mesh manipulations or decoupling the solid and fluid motion. Despite the wealth of progress recently made in mechanics modeling, this glaring inadequacy persists. We propose a new technique that tracks the interface implicitly and circumvents the need for remeshing and remapping the solution onto the new mesh. The solid-fluid boundary is tracked with a level set algorithm that changes the equation type dynamically depending on the phases present. This novel approach to coupled mechanics problems promises to give accurate stresses, displacements and velocities in both phases, simultaneously.

Schunk, Randy; Heroux, Michael A.; Rao, Rekha R.; Baer, Thomas A.; Subia, Samuel R.; Sun, Amy C.; Heroux, Michael A.

Abstract not provided.