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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Reuben T. Sorensen, John C. Lee
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 213-230
Technical Paper | doi.org/10.13182/NSE08-A2749
Articles are hosted by Taylor and Francis Online.
We have developed a light water reactor (LWR) equilibrium cycle search algorithm that is similar to the REBUS-3 fast reactor methodology but with depletion capabilities typically employed for LWR analysis. Our LWR methodology projects the original coupled nonlinear isotopic balance equations to a series of equations that are piecewise linear in time. Iterations are performed on microscopic reaction rates until the linearized isotopic balance equations yield an ultimate equilibrium state. We further reduce the computational burden associated with LWR analysis by approximating global depletion calculations with assembly-level, collision probability calculations performed by the CASMO-3 code. We demonstrate the benefits of our equilibrium cycle methodology by calculating the true equilibrium Pu inventory of two configurations: a heterogeneous assembly configuration that contains both low enriched UO2 and mixed oxide (MOX) fuel pins and a homogeneous configuration comprising a 2 × 2 colorset arrangement of MOX and low enriched UO2 assemblies. For each configuration our methodology yields a true equilibrium Pu inventory with only 12 CASMO-3 lattice physics calculations. As a validation, an inventory extrapolation technique is used to arrive at a quasi-equilibrium cycle for both LWR configurations. The extrapolated technique yields a similar Pu inventory and isotopic composition but requires 65 lattice physics calculations.