Sloshing in a square liquid tank subjected to horizontal harmonic excitation is investigated.

In the theoretical analysis, the modal equations of motion for seven sloshing modes are

obtained considering the nonlinearity of sloshing, and then the theoretical response curves

are calculated. The validity of the theoretical analysis was confirmed by comparing the

theoretical response curves with the experimental data.

Experimental Setup

Sloshing Modes

Nonlinear Liquid Sloshing (1)

Experimental and Theoretical Response Curves

(1,0) (0,1)

(2,0) (0,2)

(3,0) (0,3)

(1,1)

Nonlinear sloshing dynamics in a

cylindrical liquid tank subjected

to horizontal harmonic excitation

is investigated. Theoretical

response curves were in good

agreement with the experimental

data.

Nonlinear Liquid Sloshing (2)

R＝60 mm, h=72 mm, p11=2.727 Hz,

a cos wt ＝0.57 cos wt [mm]

② Chaotic Motion

③ Swirl Motion

① Planar Motion

Theoretical Model Experimental and Theoretical Response Curves

①

②

③

③

①

②

Vibration Control of Elastic Structures

Utilizing a Cylindrical Tank

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TLDs

Shin-Yokohama Prince Hotel (149 m tall)

Theoretical Frequency Response Curves

Experimental Apparatus

Mechanism of Suppression

Suppressed

Fluid Force

Fluid Force

Displacement Displacement

The performance of cylindrical tuned

liquid dampers (TLDs) is investigated

to suppress the vibrations of elastic

structures subjected to horizontal

harmonic excitation. Response curves

are analytically calculated by

considering the nonlinear fluid force

due to sloshing. They show the

effectiveness of cylindrical TLDs.

Theoretical Model

Vibration Control of Elastic Structures

Utilizing Two Rectangular Tanks

Experimental Setup

The performance of TLDs is investigated when two

rectangular tanks are used. The liquid elevations

were observed in different amplitudes even if these

tanks are identical. Amplitude modulated motions

(AMMs) appear when the liquid levels are

comparatively high.

Experimental time

histories at f=2.561 Hz. Theoretical Response Curves

Vibration Control of Elastic Structures

Utilizing a Rectangular Tank (Vertical Excitation)

Tuned liquid dampers (TLDs) are also effective to suppressed the vibrations of

elastic structures subjected to vertical excitation. The optimal liquid level exists.

If the tuning condition was deviated, the performance of TLDs decreases

because amplitude modulated motions (AMMs) could appear.

Theoretical Model Response curves for the

optimal liquid level

Response curves where

AMMs appear.

A square tuned liquid damper (TLD) is used to suppress

the vibrations of an elastic structures subjected to

vertical harmonic excitation. Square TLDs work more

effectively for lower liquid levels than rectangular TLDs.

Experimental and theoretical

Response Curves Experimental Setup Experimental time

histories at f=5.540 Hz.

Vibration Control of Elastic Structures

Utilizing a Square Tank (Vertical Excitation)