To design proper seals, it is important to understand seal behavior and joint and crack geometry. Different seal cross sections are compared, namely, rectangular, trapezoidal, and trapezoidal-rectangular shapes. After a closed-form solution could not be achieved usingthe theory of elasticity, the plane strain, nonlinear, incompressible, hyperelastic (Mooney-Rivlin) finite element formulation of the software ABAQUS was used to evaluate different seal cross-sections intension and compression with emphasis on bulge and sag and on shearstrain (e sub-12). Laboratory measurements using Silicone Dow Corning 888 were taken to determine bulge and sag. It was concluded that the most desirable cross section of the three shapes is the rectangular. Axial strains (e sub-11) at the surface of the seal were compared with Tons' parabolic deformation calculations. There was good agreement all along the seal surface except near the joint walls because of a singularity. With continued research, the structural responsecalculations at the joint wall interface should be improved.
Abstract