Fundamental Frequency of Water Sloshing Waves in a Sloped-Bottom Tank as Tuned Liquid Damper


In this study, the natural frequency of the water sloshing wave in a rectangular tank with various sloped bottom shapes is derived from its equivalent flat-bottom tank using the linear wave theory. In this equivalency, the bottom wet length of the tank was used to replace the flat length and the deepest water depth was taken as the water depth in the natural frequency formula of a flat-bottom tank. The calculated natural frequency was validated with experimental data. The rationale for the use of the bottom wet length in the frequency evaluation of a rectangular tank of various sloped bottom shapes is demonstrated based on the finite element coordinate transformation. Different bottom lengths change the travel distance and thus the damping ratio of the water sloshing wave in the tank. © 2009 ASCE.

Meeting Name

Structures Congress - Don't Mess with Structural Engineers: Expanding Our Role (2009: Apr. 30-May 2, Austin, TX)


Civil, Architectural and Environmental Engineering

Keywords and Phrases

Co-Ordinate Transformation; Damping Ratio; Experimental Data; Finite Element; Frequency Evaluation; Fundamental Frequencies; Linear Wave Theory; Rectangular Tank; Travel Distance; Tuned Liquid Dampers; Water Depth; Water Sloshing; Fluid Structure Interaction; Natural Frequencies; Tanks (Containers); Liquid Sloshing

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


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© 2009 American Society of Civil Engineers (ASCE), All rights reserved.