Chemical kinetics and thermal hydraulics of lead bismuth flow loops
Abstract
The objective of the thesis is to study the effect of chemical kinetics and thermal hydraulics of Lead Bismuth Eutectic (LBE) flow in the Materials Test Loop (MTL). The Materials Test Loop, also known as the Delta Loop, was built in Los Alamos National Laboratories (LANL) to obtain the experimental data for corrosion estimation and analysis. It is a well-known fact that corrosion plays an important role in the design of nuclear thermal hydraulic systems. Since the MTL is a multi-section closed system that differs in diameter from one part to another, an intensive study on the overall and regional corrosion distribution is necessary and valuable. In previous studies, experimental data on this research area is very limited and far from accurate and complete; Flow simulations using a commercial Computational Fluid Dynamics code, analysis of the flow dynamics and estimation of corrosion in the MTL due to the LBE flow, by assuming simplified geometries for the MTL, are the topics of discussion. For the flow analysis and corrosion estimation, three simplified geometries of the MTL have been assumed, results from one assumption leading to the other. Wall concentrations obtained from previous analytical studies have been used to impose the boundary conditions on the model; Results from flow simulation and theoretical analyses have been compared which seem to be in good agreement. The improvement in this work is the prediction of the corrosion flux at elbows due to the multidirectional nature of the flow. The results are beneficial for the future design of the thermal hydraulic loop to minimize corrosion at critical points.