Dynamic and whipping response of the surface ship subjected to underwater explosion: experiment and simulation

The prediction of surface ship response to a far-field underwater explosion (UNDEX) requires the simulation of shock wave propagation in the fluid, cavitation, fluid-structure interaction, and structural response. Effective approaches to model the fluid include cavitating acoustic finite element (CAFE) and cavitating acoustic spectral element (CASE) methods. Although the spectral element method offers the potential for greater accuracy at lower computational cost, it also generates more spurious oscillations around discontinuities which are difficult to avoid in shock-related problems. Thus, the advantage of CASE remains unproven. In this paper, we present a 3D-partitioned FSI framework and investigate the application of CAFE and CASE to a surface ship early-time far-field UNDEX problem to determine which method has the best computational efficiency for this problem. We also associate the accuracy of the structural response with the modeling of cavitation distribution. A further contribution of this work is the examination of different nonmatching mesh information exchange schemes to demonstrate how they affect the structural response and improve the CAFE/CASE methodologies.

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Simplified modelling of surface ship whipping response to underwater explosion

Developments in the Collision and Grounding of Ships and Offshore Structures ◽

10.1201/9781003002420-15 ◽

2019 ◽

pp. 120-126

Author(s):

R. Trivedi ◽

H. Le Sourne ◽

S. Paroissien ◽

S. Branchereau ◽

C. Lucas

Keyword(s):

Underwater Explosion ◽

Surface Ship

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Surface Ship Shock Modeling and Simulation: Two-Dimensional Analysis

Shock and Vibration ◽

10.1155/1998/967539 ◽

1998 ◽

Vol 5 (2) ◽

pp. 129-137 ◽

Cited By ~ 23

Author(s):

Young S. Shin ◽

Leonard D. Santiago

Keyword(s):

Modeling And Simulation ◽

Surface Effect ◽

Fluid Model ◽

Fluid Structure Interaction ◽

Underwater Explosion ◽

Two Dimensional ◽

Bubble Behavior ◽

Fluid Structure ◽

Structure Interaction ◽

Surface Ship

The modeling and simulation of the response of a surface ship system to underwater explosion requires an understanding of many different subject areas. These include the process of underwater explosion events, shock wave propagation, explosion gas bubble behavior and bubble-pulse loading, bulk and local cavitation, free surface effect, fluid-structure interaction, and structural dynamics. This paper investigates the effects of fluid-structure interaction and cavitation on the response of a surface ship using USA-NASTRAN-CFA code. First, the one-dimensional Bleich-Sandler model is used to validate the approach, and second, the underwater shock response of a two-dimensional mid-section model of a surface ship is predicted with a surrounding fluid model using a constitutive equation of a bilinear fluid which does not allow transmission of negative pressures.

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