Dynamic response analysis of a liquid-filled cylindrical tank with annular baffle

AR & DB Centre of Excellence for Composite Structures Technology, Department of Aerospace Engineering, Indian Institute of Technology, Kharagpur 721302, India; Department of Civil Engineering, Indian Institute of Technology, Kharagpur 721302, India
Journal of Sound and Vibration (Impact Factor: 1.61). 01/2004; DOI: 10.1016/S0022-460X(03)00568-6

ABSTRACT Baffles are generally used as damping devices in liquid storage tanks. The focus of the present paper is to study the influence of a baffle on the dynamic response of a partially liquid-filled cylindrical tank. A baffle is assumed here to have the shape of a thin annular circular plate. The natural frequencies of an inviscid and incompressible liquid are determined for varying positions and dimensions of a baffle attached normal to the tank wall. The flexibility of both the baffle and the tank are considered in studying the effects of liquid–baffle and liquid–tank interactions on the sloshing mode frequencies. Finite element codes are developed and are then used to analyze both the liquid domain and the structural domain (i.e., the tank and the baffle). The coupled vibration frequencies of the tank–baffle system are computed considering the effect of sloshing of liquid. The results obtained for a liquid-filled elastic tank without a baffle and a rigid tank with a rigid baffle are in good agreement with the available results. The slosh amplitude of liquid in a rigid tank with and without a rigid baffle is studied under translational base excitation. The effects of the tank wall and baffle flexibility on the slosh response are also investigated.

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