Contacts in a system are often defined when the load path can change during operation due to bodies touching each other. One example is the compression of a multi-cell sealing profile, where internal block formation in a cell increases the force-displacement progression.

Another typical application is the analysis of a flange to assess sealing performance. Contacts are always required where only compressive forces can be transmitted. A special type of contact, the “tied contact,” allows different meshes to be connected, saving significant meshing time in certain cases.

For these tasks, we use ABAQUS, ANSYS, and MSC/Marc.

Examples:

• Contact analysis under centrifugal, vapor pressure, and thermal loads
• Sealing deformation with self-contact
• Analysis of a strut mount support bearing with bolt pretension

Geometric nonlinearity must be considered when system stiffness changes due to component deformation. This option is selected in nearly all nonlinear analyses.

An implicit dynamic analysis is preferred over a static analysis whenever inertia effects or vibrations can influence the overall result and non-negligible nonlinearities are present.

At our company, nearly all kinematic calculations—such as linkages of soft or hard tops and tailgate mechanisms—are performed using this method. Compared to conventional rigid-body kinematics, the main advantage is that we can simulate reality almost without restrictions. Using a power-controlled hydraulic system, we can open and close the kinematics in real time with all components and stops.

In addition to force requirements and joint loads, the elastic analysis provides information on the uniformity of motion and the stresses in each component throughout the movement. Contacts and nonlinear material properties of any kind can also be accounted for.

When the stress in a component exceeds the material’s yield strength, a nonlinear material model should be used. The plastic strain curve—typically obtained from material tests—describes the deformation behavior up to the allowable upper yield limit.

Elastomers represent another type of nonlinear material behavior. Parameters for coefficient-based material models are determined either from the “Shore hardness” or via curve fitting based on your test data.

If material data are not available in our database or from you, we can determine the necessary material parameters. In addition to standard DIN tests for metallic materials, we also define completely new, problem-oriented test scenarios for alternative composite materials, usually in collaboration with various university institutes.

For these tasks, we use ABAQUS, ANSYS, and MSC/Marc.

Examples:

• Plastically deformed latch hook
• Strut mount bent after driving over a curb
• Test setup for a fiber-reinforced composite
• Derived calculation model for a fiber-reinforced composite
• In-house development of a calculation model for fabric folding