LARGE DEFORMATION ANALYSIS OF A RUBBER BOOT SEAL USING NONLINEAR STATIC FINITE ELEMENT METHODS

Abstract

Rubber boot seals are critical components in mechanical and automotive systems, where they must
accommodate large axial and torsional deformations while maintaining reliable sealing
performance. This study presents a nonlinear static finite element analysis of a rubber boot seal
assembled over a cylindrical shaft. A half-symmetry three-dimensional model is developed in
ANSYS Mechanical to capture geometric, material, and contact nonlinearities. The rubber material
is modeled using a Neo-Hookean hyperelastic formulation to represent large elastic strains, while
the shaft is idealized as a rigid body. Three contact regions are defined: a rigid–flexible frictional
interface between the boot and shaft, and two self-contact regions on the inner and outer boot
surfaces. The analysis is conducted in three sequential load steps: interference fit, axial
compression, and combined axial compression with shaft rotation. Results demonstrate significant
nonlinear deformation, stress concentration near geometric transitions and contact regions, and
strong coupling between frictional contact and hyperelastic material response. The study confirms
the necessity of advanced nonlinear modeling techniques for realistic prediction of rubber sealing
performance.