On sloshing in a container with moving wall

Abstract The research on the coupled frequencies of a fluid–structure system comprised of a container with a moving wall partially filled with water (Figure 1) was presented in two papers by Lu et al. and Chai et al. , but their solutions are different. The aim of this letter is to compare them. The fluid is incompressible and inviscid, and the structure is a mass m [kg m −1 ] in translation, connected to the Galilean reference by a spring of stiffness k [N m −2 ]; these characteristics are given per unit length in the z direction. The authors linearized the equations and looked for a potential-flow solution for the fluid motion. They obtain the same set of equations.