Effect of natural frequency modes on sloshing phenomenon in a rectangular tank

• Main Authors: Jae Hwan Jung, Hyun Sik Yoon, Chang Yeol Lee
• Format: Article
• Language: English
• Published: Elsevier 2015-05-01
• Series: International Journal of Naval Architecture and Ocean Engineering
• Subjects: Liquid sloshing; Natural frequency modes; Level set method
• Online Access: http://www.sciencedirect.com/science/article/pii/S2092678216300668

Liquid sloshing in two-dimensional (2-D) and three-dimensional (3-D) rectangular tanks is simulated by using a level set method based on the finite volume method. In order to examine the effect of natural frequency modes on liquid sloshing, we considered a wide range of frequency ratios (0.5 ≤fr≤ 3.2). The frequency ratio is defined by the ratio of the excitation frequency to the natural frequency of the fluid, and covers natural frequency modes from 1 to 5. When fr= 1,which corresponds to the first mode of the natural frequency, strong liquid sloshing reveals roof impact, and significant forces are generated by the liquid in the tank. The liquid flows are mainly unidirectional. Thus, the strong bulk motion of the fluid contributes to a higher elevation of the free surface. However, at fr= 2,the sloshing is considerably suppressed, resulting in a calm wave with relatively lower elevation of the free surface, since the waves undergo destructive interference. At fr= 2,the lower peak of the free surface elevation occurs. At higher modes of fr3, fr4, and fr5, the free surface reveals irregular deformation with nonlinear waves in every case. However, the deformation of the free surface becomes weaker at higher natural frequency modes. Finally, 3-D simulations confirm our 2-D results.