Numerical investigation of the hydrodynamic interaction between two underwater bodies in relative motion

The paper presents a strip theory and its correlation with experiment and analysis on the relative motions of two ships. The ships are in close proximity and in parallel position in oblique waves. The two-dimensional procedure takes account of the hydrodynamic interaction between two cylindrical bodies. It was found that the strip method is a useful technique to predict the hydrodynamically coupled motions of two ships.

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Transient Analysis of Hydrodynamic Interaction Effects on an Autonomous Underwater Vehicle in Proximity of a Moving Submarine

10.3940/rina.ijme.2015.a4.320 ◽

2015 ◽

Vol 157 (A4) ◽

pp. 205-218

Keyword(s):

Relative Motion ◽

Transient Analysis ◽

Hydrodynamic Interaction ◽

Autonomous Underwater Vehicle ◽

Underwater Vehicle ◽

Cfd Simulations ◽

Close Proximity ◽

Computational Fluid Dynamics Cfd ◽

Submarine Hull ◽

Hull Forms

"When an Autonomous Underwater Vehicle (AUV) is operating close to a moving submarine, the hydrodynamic interaction between the two vehicles can prevent the AUV from maintaining its desired trajectory. This can lead to mission failure and, in extreme cases, collision with the submarine. This paper outlines the transient interaction influence on the hydrodynamic coefficients of an AUV operating in close proximity and in relative motion to a larger moving submarine. The effects of relative motion on the interaction behaviour were investigated via two manoeuvres, i.e. the AUV overtaking and being overtaken by the submarine at different relative forward velocities and lateral distances. The results presented are from a series of Computational Fluid Dynamics (CFD) simulations on axisymmetric AUV and submarine hull forms, with validation of the CFD model carried out through scaled captive model experiments. The results showed that an AUV becomes less susceptible to the interaction influence when overtaking at speeds higher than the submarine. The implications of the interaction influence on the AUV’s ability to safely manoeuvre around the submarine are also discussed."

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Transient inertial hydrodynamic interaction between two identical spheres settling at small Reynolds number

Journal of Fluid Mechanics ◽

10.1017/s0022112008001523 ◽

2008 ◽

Vol 605 ◽

pp. 263-279 ◽

Cited By ~ 2

Author(s):

B. U. FELDERHOF

Keyword(s):

Reynolds Number ◽

Kinetic Energy ◽

Relative Motion ◽

Hydrodynamic Interaction ◽

Stokes Equations ◽

Navier Stokes ◽

Small Reynolds Number ◽

Navier Stokes Equations ◽

Small Constant ◽

Distance Vector

The flow pattern generated by a sphere accelerated from rest by a small constant applied forceshows scaling behaviour at long times, as can be shown from the solution of the linearized Navier–Stokes equations. In the scaling regime the kinetic energy of the flow grows with thesquare root of time. For two distant settling spheres starting from rest the kinetic energy ofthe flow depends on the distance vector between centres; owing to interference of the flowpatterns. It is argued that this leads to relative motion of the two spheres. Thecorresponding interaction energy is calculated explicitly in the scaling regime.

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Hydrodynamic interaction between gas bubbles in liquid

Journal of Fluid Mechanics ◽

10.1017/s0022112076001110 ◽

1976 ◽

Vol 77 (1) ◽

pp. 27-44 ◽

Cited By ~ 126

Author(s):

L. Van Wijngaarden ◽

D. J. Jeffrey

Keyword(s):

Relative Motion ◽

Momentum Flux ◽

Hydrodynamic Interaction ◽

Liquid Mixture ◽

Gas Bubbles ◽

Gas Bubble ◽

Virtual Mass ◽

Bubble Liquid ◽

The One

A calculation is given of the velocity which a cloud of identical gas bubbles acquires when the liquid in which the cloud is immersed is impulsively accelerated. From the results an expression follows for the effective virtual mass of a bubble in a gas-bubble/liquid mixture. Further consideration is given to that part of the momentum flux in the mixture associated with relative motion between liquid and bubbles. An expression for this quantity is derived which appears to differ from the one used in practice. It is shown that qualitative support for the expression obtained here is provided by experimental observations reported in the literature.

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