All structures respond to external loads in a nonlinear fashion. However, the nonlinear nature is profound and important in only certain cases. There are several linear and nonlinear solvers that are available to analyze these systems and picking the correct solver is often a choice between computational cost and accuracy. Typically, there are three sources of nonlinearities:
In this lesson, we will simulate the large strain necking of a tensile bar specimen by considering different types of nonlinearities.
The tensile test is a basic testing method to obtain many mechanical properties of materials, like Young’s modulus, Poisson's ratio, yield strength and tensile strength. Check this simulation and try to discover what type of nonlinearity it demonstrates. How will removing these nonlinearities influence the force–displacement result? (Note that due to symmetry, only one-quarter of the specimen is modeled).