Numerical Investigation of Sloshing Motion Inside Tuned Liquid Dampers With And Without Submerged Screens

Abstract

<p> A numerical algorithm has been developed to solve the sloshing motion of liquid in a Tuned Liquid Damper (TLD) outfitted by slat screens under large and random amplitude of excitation. It is based on the finite-difference method. The free surface has been reconstructed using volume of fluid method. Donor-acceptor technique has been used for tracking the volume fraction field. The effect of slat screen has been included and modeled using the partial cell treatment method. </p> <p> The algorithm is an integrated fluid-structure model where the response of the structure is determined considering the effects of TLD. The structure is assumed as a single degree of freedom system (SDOF) and its response is calculated using the Duhamel integral method. </p> <p> The algorithm has been validated against experimental data for the cases with and without screens. An excellent agreement was obtained between numerical and experimental results. </p> <p> An extensive parametric study has been carried out investigating the effect of slat screens and screen pattern on the TLD performance and on the structure response. A new parameter termed as slat ratio was introduced to characterize the slat screens based on their pattern. Results indicated that screen pattern has a significant effect on the TLD performance and it could lead up to 33 % reduction in structure response. It was found that decreasing the slat ratio will increase the damping effect of a TLD outfitted by slat screen. </p> <p> The validity of the most commonly used approach, Baines and Peterson model, to calculate pressure drop of slat screens has been investigated. A conelation factor as a function of Reynolds number and solidity ratio of screen has been proposed to improve the results of this model. A new concept termed as effective solidity ratio has been proposed to account for the physical significant of screen pattern on TLD performance. </p>