1. Fluid forces acting on a vibrating structure

There are two families of fluid forces that can to affect a vibrating structure in a fluid medium:

1. fluid-elastic forces: these are forces that depend on the movement of the structure; on its displacement, its speed, and its acceleration. Therefore, it is appropriate to take into account these fluid-elastic coupling effects by adding coefficients to the structural matrices of stiffness, mass and damping.

2. The forces independent of the movement of the structure. These are the forces that act in the case of turbulent or two-phase flows.

In this document we present the various Code_Aster operators that make it possible to model each of the two types of fluid forces in the context of vibratory analyses of structures.