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Date:2019-03-13

Indexed by:Journal Article

Date of Publication:2018-12-01

Journal:APPLIED OCEAN RESEARCH

Included Journals:Scopus、SCIE

Volume:81

Page Number:76-92

ISSN:0141-1187

Key Words:Oblique water entry; Six-degree-of-freedom; Large eddy simulation; Vortex structure; Dynamic characteristics

Abstract:Water entry problem is an important topic, and the physical understanding of the mechanism of the cavity dynamics and vortex evolution have still not been clear up to now. In the present study, the complicated unsteady characteristics for the oblique water entry problem of a cylinder were investigated both numerically and experimentally. In the numerical study, a three-dimensional simulation with a six-degree-of-freedom model was carried out, where the large eddy simulation (LES) model and the volume of fluid (VOF) technique were used for turbulence computation and air-liquid interface tracking, respectively. In order to provide the validation data for the numerical calculation, the corresponding experiment was carried out, in which a high-speed camera was used to record the cavity evolution. The cavity evolution mechanism and flow pattern at a low Froude number are analyzed and it is found that the multi-scale vortex structures around the cylinder can be successfully captured by LES method. Moreover, a numerical parametric study is conducted on the effects of water entry angle on the dynamic characteristics numerically.