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SLOSHING IN A T-BAFFLED RECTANGULAR STORAGE TANK 13
NUMERICAL STUDY FOR 2–D PROBLEMS

SLOSHING IN A T-BAFFLED RECTANGULAR STORAGE TANK
NUMERICAL STUDY FOR 2–D PROBLEMS

Hakan AKYILDIZ*
* İstanbul Teknik Üniversitesi

ABSTRACT

The liquid sloshing in a moving partially filled rectangular tank with vertical and T-shape baffles is
investigated. A numerical algorithm based on the volume of fluid technique (VOF) is used to study the
non-linear behaviour of liquid sloshing. The numerical model solves the complete Navier-Stokes
equations in primitive variables by using of finite difference approximations with the moving coordinate
system. The ratio of the baffle height to the initial liquid depth has been changed in the range of 0 ≤ hB /
h ≤ 1.0. The effect of the T-shape baffle and vertical baffle height to reach the roof of the tank have been
investigated. It is observed that a vertical baffle for hB / h < 0.8 would be more effective except the
maximum dynamic pressure at T2 and T-shape baffle having a height hB / h ≥ 0.8 would be very
effective in reducing the dynamic pressure. On the other hand, the maximum overturning moment for the
T-baffled case would be much smaller. In order to assess the accuracy of the method used, some results
with vertical baffle are compared with the available experimental results. The time variations of pressures
have been also presented.

Keywords: Sloshing, Two-dimensional free surface flow, Volume of fluid technique, Finite difference
method, T-Baffle

1. Introduction

Liquid sloshing in a moving tank constitutes major components in a number of dynamical
systems such as aerospace vehicles, road tankers, liquefied natural gas carriers, elevated water
towers and petroleum cylindrical tanks. Fluid motion in partially filled tanks can cause large
structural loads if the period of tank motion is close to the natural period of fluid inside the tank
(Ibrahim, 2005; Faltinsen and Timokha, 2009). The amplitude of the slosh, in general, depends
on amplitude and frequency of the tank motion, liquid-fill depth, liquid properties and tank
geometry. These parameters have direct effects on the dynamic stability and performance of
moving tanks. The baffle inside a tank has investigated many researchers and the several recent
studies on the effect of baffle on liquid sloshing are summarized as follows.

There has been a considerable amount of work on liquid sloshing. Some of these studies are
reported by Ibrahim et al. (2001), Faltinsen and Timokha (2001). Faltinsen and Timokha,
(2001) analysed the two-dimensional nonlinear sloshing of an incompressible fluid with
irrotational flow in a rectangular tank by a modal theory. The theory they used is in good
agreement with experimental results but the model assumes infinite tank roof height.

Akyildiz and Unal (2005; 2006) investigated the pressure variations in both baffled and
unbaffled rectangular tank numerically and experimentally. They observed that the effects of the

Sayı 1, 2014 GiDB|DERGi