Spent nuclear liquid waste is often kept in partially filled storage tanks. When such storage tanks are subjected to wind and/or earthquake induced excitations, this could lead to detrimental conditions. Therefore, storage tank designers should ensure safe design margins and develop methodologies to overcome a wide range of possible scenarios. In the present study, systematic numerical simulations are carried out to investigate the sloshing dynamics of liquid in a storage tank, subjected to seismic excitation. As a precursor, the influence of resonant harmonic excitation on the free surface displacement, pressure distribution, slosh forces etc. is studied. To suppress the free surface fluctuations and the associated slosh force, two types of baffles viz., ring and vertical baffle are examined. Based on the response to an imposed harmonic excitation, the vertical baffle plate in the middle of the tank, was found to be effective and its dimensions are systematically optimized. This baffle geometry was tested for a well known seismic excitation (El Centro) and it was observed to effectively suppress free surface fluctuations and the slosh forces. © 2016 Elsevier Ltd. All rights reserved.

B. S.V. Patnaik

Department of Applied Mechanics

V. S. Sanapala

Computational fluid dynamics

Computer simulation

Fuel sloshing

Fuel storage

Fuel tanks

Liquids

Numerical models

Seismology

SPENT FUELS

Tanks (containers)

FREE SURFACE FLUCTUATION

Fuel applications

Harmonic excitation

NUCLEAR SPENT FUELS

RESONANT HARMONICS

Seismic excitations

SLOSHING DYNAMICS

Thermal hydraulics

Liquid sloshing

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Annals of Nuclear Energy

In the present study we perform shake table experiments to study the fluid structure interaction effects between the sloshing liquid and the internal structure. A partially filled storage tank is systematically subjected to (i) horizontal (ii) vertical and (iii) seismic excitations. To start with, forced horizontal excitations are imposed by varying the amplitude of excitation ranging from 0.001 L to 0.0075 L, where, L is the tank length. As the amplitude of excitation is increased, sub-harmonic wave features were observed at the wave crests, which indicate the presence of higher slosh modes. The resulting resonant free surface oscillations are validated against available theoretical and computational studies. Furthermore, the tank was subjected to vertical harmonic excitations at nth slosh frequency (ω n ), where, n = 1, 2, 3 and 4 covers first four sloshing modes. The excitation frequency (Ω n = ω n ∕ω v ) of 0.5 and the corresponding forcing amplitudes (κ v ) are chosen such that, the combinations were with in the unstable range of Matheiu's instability diagram. For higher modes of vertical excitation, the free surface oscillations were found to be better damped. A detailed study of flow visuals, free surface fluctuations, dynamic pressure data, power spectral densities, structural responses etc reveal the nature of coupling with the container wall and the circular cylinder. The shake table is further programmed to simulate the well known El Centro earthquake excitation, where the storage tank is imposed with horizontal as well as combined horizontal and vertical components of excitation (at 50% of actual amplitude) to investigate the fluid structure interaction effects. When the partially filled storage tank is subjected to seismic excitation, spiky jet like features were observed over the free surface. © 2019

Journal of Sound and Vibration

An experimental investigation on the dynamics of liquid sloshing in a rectangular tank and its interaction with an internal vertical pole

Liquid sloshing is a problem of serious concern in partially filled tanks. Tank designers must ensure safe margins and develop methodologies to overcome a wide range of plausible situations related to transport, wind, earthquake loads etc. to assess the structural stability. In the present study, numerical simulations are carried out to investigate the sloshing dynamics of a partially filled rectangular container, subjected to vertical harmonic as well as seismic excitations. Unlike horizontal excitation, participation of higher modes is of prime concern in vertical (parametric) excitations. The present study numerically simulates and explores methodologies to control the slosh forces and free surface oscillations with the help of a baffle. Detailed numerical validations are carried out against other experimental and computational studies from the literature. Sloshing dynamics under imposed vertical harmonic excitations was investigated at its first and third modes. Based on a detailed study of transient wave profiles, force and pressure time histories, optimal baffle design was achieved. Optimal position of the baffle and its width are systematically obtained with reference to the quiescent free surface. The effectiveness of this baffle was tested against the well known Bhuj earthquake in India. © 2017

Journal of Fluids and Structures

Numerical simulation of parametric liquid sloshing in a horizontally baffled rectangular container

In a number of chemical and nuclear engineering applications, a cover gas is maintained above a liquid pool. In a fast breeder reactor (FBR), argon gas is maintained above the sodium pools to ensure no direct contact between air and liquid sodium. Nevertheless, argon entrains into sodium by a variety of mechanisms, which is detrimental to the reactivity of the core. Furthermore, a large number of components that remain partially submerged in the liquid pool, aid in this undesirable gas entrainment process. The present study numerically explores liquid fall induced gas entrainment in an FBR hot pool. A passive strategy to mitigate gas entrainment is suggested in the form of a circumferential baffle plate. An optimal design for the baffle is achieved through systematic Computational Fluid Dynamic (CFD) simulations. © 2013 Elsevier Ltd. All rights reserved.

International Journal of Heat and Mass Transfer

Numerical simulation of liquid fall induced gas entrainment and its mitigation

Experimental and numerical study of dynamic response of elevated water tank of AP1000 PCCWST considering FSI effect

External flooding event analysis in a PWR-W with MAAP5

Experimental investigation of slosh parametric instability in liquid filled vessel under seismic excitations

Nuclear Engineering and Design

Safety goals for seismic and tsunami risks: Lessons learned from the Fukushima Daiichi disaster

CFD simulations on the dynamics of liquid sloshing and its control in a storage tank for spent fuel applications

Journal	Data powered by TypesetAnnals of Nuclear Energy
Publisher	Data powered by TypesetElsevier Ltd
ISSN	03064549
Open Access	No