Development, verification, and validation of comprehensive acoustic fluid‐structure interaction capabilities in an open‐source computational platform

Abstract

The acoustic fluid-structure interaction (FSI) formulation is a practical numerical approach for the seismic analysis of fluid-filled tanks. However, there are no verification and validation studies reported in the literature that demonstrate the ability of an acoustic FSI numerical model to predict responses important to structural and mechanical design for intense translational and rotational earthquake inputs. Herein, an acoustic FSI formulation is implemented in the opensource Multiphysics Object-Oriented Simulation Environment (MOOSE), and is formally verified and validated using analytical solutions and code-to-code verification, and experimental data, respectively. The analytical solutions are for small amplitude, unidirectional seismic inputs. The code-to-code verification utilizes a previously verified and validated Arbitrary Lagrangian-Eulerian (ALE) numerical model in the commercial finite element code LS-DYNA. The validation studies utilize a comprehensive data set assembled from results of 3D earthquake-simulator tests of a fluid-filled vessel. The acoustic numerical model in MOOSE is verified and validated for hydrodynamic pressures and support reactions except for cases that involve significant convective response. For small amplitude inputs, numerically predicted wave heights match those of the analytical solutions. The numerical model is not verified and validated for wave height calculations under intense 3D seismic inputs. The run times for the acoustic FSI simulations in MOOSE are an order of magnitude, or more, shorter than for the corresponding ALE simulations in LS-DYNA. The utility of the MOOSE acoustic FSI implementation is demonstrated by seismic analysis of a building equipped with a fluid-filled, advanced nuclear reactor.

A risk‐targeted seismic performance assessment of elephant‐foot buckling in walls of unanchored steel storage tanks

“…9 The seismic behaviour and fragility analysis of above-ground liquid storage tanks, including relevant failure modes, has been investigated using models of different complexities. 6,[10][11][12][13][14] In the framework of quantitative risk analysis of liquid storage tanks, fragility functions can be defined in the form of probit functions. 15 However, damage states may be defined by engineering demand parameters (EDPs) obtained from the seismic analysis.…”

“…Few recent experimental studies have focussed on the stress distribution on the tank wall in above-ground liquid storage tanks. 18,19 Many researchers 12,13,20 studied above-ground liquid storage tanks using refined FE models. Their studies focussed on two models applied to the liquid domain: an arbitrary Lagrangian-Eulerian model 12 and an acoustic model.…”

“…Their studies focussed on two models applied to the liquid domain: an arbitrary Lagrangian-Eulerian model 12 and an acoustic model. 13,20 Although wall buckling may lead to leakage and loss of tank containment, non-linear effects or large deformations affecting the tank wall due to EFB have not been thoroughly studied. 4,6 However, it was observed that the occurrence of EFB does not necessarily trigger the loss of containment.…”

“…Many researchers 12,13,20 studied above‐ground liquid storage tanks using refined FE models. Their studies focussed on two models applied to the liquid domain: an arbitrary Lagrangian–Eulerian model 12 and an acoustic model 13,20 .…”

“…Many researchers 12,13,20 studied above‐ground liquid storage tanks using refined FE models. Their studies focussed on two models applied to the liquid domain: an arbitrary Lagrangian–Eulerian model 12 and an acoustic model 13,20 . Although wall buckling may lead to leakage and loss of tank containment, non‐linear effects or large deformations affecting the tank wall due to EFB have not been thoroughly studied 4,6 .…”