|Student Name:||Lt Col Suzanna J.D. McNabb|
|Thesis:||AN EXPONENTIAL MOMENT METHOD FOR MODELING TRANSIENT BEHAVIOR IN MULTICOMPONENT ISOTOPE ENRICHMENT CASCADES|
|Location:||Bldg 640, room 301 (EN Conf room)|
|Date & Time:||05/23/2013 at 1230|
|Abstract:|| A novel method for solving transient multicomponent enrichment cascades using an exponential moment matching method is presented. Transient isotope compositions in enrichment cascades are defined by a non-linearly-coupled system of differential equations. Exponential moment methods are a relatively new class of numerical integration techniques originally developed for neutron transport modeling, and have been found to be robust and fourth-order. A multicomponent cascade Fortran solver, Exponential Moment Matching Transient Solver (EMMTS) was developed to implement the new method. It determines transient component fractions at every stage using exponential moment matching to solve the non-linearly coupled relationship between stages, and has adaptive quadrature for error control. The new method is unconditionally stable, robust, and efficient. EMMTS is secondorder convergent for large multicomponent cascades, and achieves fourth-order convergence for small multicomponent cascades. Conservation (the fractions in each location sum to one exactly) is maintained throughout the solution.