Analytical and Numerical Studies of Seismic Fluid-Structure Interaction in Liquid-Filled Vessels

Keywords: Earthquake engineering, Seismic fluid-structure interaction, Verification and validation of numerical models, ALE, ICFD, Fluid-filled advanced reactors, ARPA-E

Revision: The revision updates equations and their descriptions in Section 3 and text on pages 232, 235, and 237 in Section 5. The updated equations include (3.11), (3.12), (3.13), (3.33), (3.34), (3.35), (3.49), (3.61), (3.62), (3.63), (3.82), (3.83), (3.84), (3.107), (3.108), (3.109), (3.120), (3.136), (3.137), (3.138), and (3.141). On pages 232, 235, and 237, a₁₄, a₄₁, and a₁₁ are changed to f₁₄, f₄₁, and f₁₁, respectively. Equations (5.28) and (5.29), which are related to the above-mentioned changes in Section 5, are correct as written (4/16/2021).

Abstract:
This report presents a study on seismic fluid-structure-interaction (FSI) analysis, with a focus on liquid-filled nuclear reactors. Seismic design, qualification, and risk assessment of advanced reactors will rely on numerical models to calculate fluid-structure responses of the reactor vessel, contained liquid, and submerged components. These numerical models must be verified and validated. This study verifies and validates numerical models for seismic FSI analysis. The Arbitrary-Lagrangian-Eulerian and Incompressible Computational Fluid Dynamics solvers in LS-DYNA are used to seismically analyze tanks, fluid and submerged components. Specifically, this study 1) reviews and corrects, as needed, prior analytical solutions for base-supported tanks and submerged components, 2) develops analytical solutions for seismic FSI analysis of head-supported tanks, 3) verifies numerical models using the corrected and newly-developed solutions, and 4) validates the numerical models using data from earthquake-simulator experiments. Numerical models of submerged components are verified for calculating their lateral frequencies, and those of tanks are verified and validated for calculating fluid pressures and reactions at the support, but not for calculating wave heights in the contained liquid. The products of the study are broadly applicable to the seismic analysis of base- and head-supported liquid-filled vessels.