Constraining a Uranium Reaction Mechanism Using Stochastic Optimization and Plasma Flow Reactor Measurements

The chemical processes governing the formation of nuclear debris in nuclear fireballs has been the subject of great interest for decades. However, despite years of study, no experimentally validated reaction mechanism has yet been developed for the uranium plasma-chemical system. In this work, we utilize emission measurements from a uranium plasma flow reactor to constrain the reaction rates of a previously unverified uranium reaction mechanism by performing stochastic optimization of the problem parameter space. The plasma flow reactor is particularly suitable for this task due to its inherent correlation between residence time and axial distance. This correlation enables the reactor to be approximated using a 0D kinetic model, drastically reducing the computational complexity of reaction mechanism calibration. This reduction in model complexity allows for a robust optimization of the dozens of uranium reaction channels over the entire parameter space, producing the first experimentally constrained uranium reaction mechanism.