Nonlinear equilibrium of partially liquid-filled tanks: A finite element/level-set method to handle hydrostatic follower forces

This paper deals with the nonlinear finite element computation of the prestressed state of structures partially filled with an incompressible inviscid liquid. The fluid is modeled by hydrostatic follower forces such that no volumetric fluid mesh is needed. Large deformations are taken into account and lead to the fluid height variation of the wetted surface to satisfy the fluid volume conservation. The main originality of this work lies on the use of a level-set approach to handle numerical integration on the fluid–structure interface. The method is developed on 3D problems considering a finite element quadratic mesh. Various numerical examples are computed using a Newton–Raphson algorithm and a quadratic convergence rate is reached by using consistent tangent stiffness operators. •FE computation of the nonlinear equilibrium of 3D elastic structures filled with liquid.•Level-set approach to integrate FE operators defined on the partially wetted surface.•Definition of the new Gauss point positions and curvilinear mesh of the contact line.•Numerical examples showing a quadratic convergence rate of the Newton algorithm.