Skip to main content

O-Ring Analysis Using Advanced Elastomeric Material Laws with LS-DYNA

LS-DYNA Consulting Services - O-Ring Rubber Analysis

Analysis

LS-DYNA

Objective

Efficient FEA analysis of elastomeric (rubber and silicone) O-Ring systems for sealing pressure verification and mechanical functionality.

The analysis of O-rings has historically been difficult since the modeling process involves large displacement and large nonlinear strains couple to multi-body contact between the O-ring, its gland cavity and the mating part. In our prior engineering services work, we would have to run the model in explicit mode and just live with the long run times even through the model was axisymmetric. In the last couple of years, the implicit capabilities of LS-DYNA have significantly grown and we can now run such models much faster and with no inertia effects.

In this case study note, we’ll cover four different O-ring simulations that we have done as LS-DYNA consulting services projects. Each project presents a different type of challenge using different material models and element types from 2-D plane strain to axisymmetric. Figure 1 provides a snapshot of the four models discussed in this note.

For those that enjoy an animated tour, please see this YouTube video and for standard text view please read-on:

-

 

Figure 1 - Different O-Ring simulations from 2-D to Axisymmetric - LS-DYNA Consulting Services
Figure 2  - Classic Mooney-Rivlin idealization to the more accurate exact stress-strain formulation of MAT_181 - LS-DYNA Consulting Services
Figure 3 - Snap-through followed by high-pressure O-ring sealing
Figure 4 - O-Ring compression following by CTE expansion to release of clamp (spring-back) - LS-DYNA Consulting Services
Figure 5 - Open O-Ring seal compaction and high-stiffness rubber latch mechanism crush to failure simulation