I have a basic knowledge on added mass modeling for AUVs. Is there any study in detail?

Added Mass and Inertia

Added (virtual) mass should be understood as pressure-induced forces and moments due to a forced harmonic motion of the body, which are proportional to the acceleration of the body [6].

The additional inertia of the fluid surrounding the body, which is accelerated by the movement of the body, has to be considered when an AUV is moving in a fluid. This effect can generally be neglected in the air environment. However, in underwater applications the density of the water, ρ ≈ 1000 kg/m3, is comparable with the density of the vehicles. In particular, at zero degrees, the density of the fresh water is 1002.68 kg/m3; for sea water with 3.5% of salinity it is ρ = 1028.48 kg/m3.

A force is necessary to achieve acceleration (the fluid exerts a reaction force which is equal in magnitude and opposite in direction) since the fluid surrounding the body is accelerated with the body itself. This reaction force is called the added mass [10].

The added mass is not a quantity of fluid to add to the system such that it has an increased mass. Different properties hold with respect to the six by six inertia matrix of a rigid body due to the fact that the added mass is a function of the body’s surface geometry. As an example, the inertia matrix is not necessarily positive definite. The added mass has also an added Coriolis and Centripetal contribution.

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