Deformation Analysis
Mathematical frameworks in solid mechanics describe the progression of deformation by tracking small changes in shape at each step of a process. The strain increment formulation updates the geometry of a body by adding infinitesimal displacements to the previous state. This approach is essential for modeling materials that undergo large deformations or exhibit non linear behaviour.
It allows for the accurate simulation of manufacturing processes such as metal forming or extrusion.
Stepwise Integration
Calculations for the stress state depend on the historical sequence of these small movements. Using a strain increment formulation ensures that the rotational components of the movement are correctly handled within the coordinate system. If the steps are too large, the mathematical error accumulates and the final shape of the object will be incorrect.
Software developers use this method to maintain numerical stability in complex structural simulations.
Path Dependency
Material properties often change as the deformation progresses due to hardening or thermal effects. The strain increment formulation allows the simulation to update the stiffness matrix at every interval to capture these changes. This is particularly important for metals that become stronger as they are worked.
The accuracy of the result depends on the quality of the constitutive laws provided for the material.
Plasticity Model
Verification of the simulation results involves checking the balance of forces at each node of the model. The strain increment formulation provides a robust way to handle the contact between different parts of the assembly. If the simulation fails to converge, the size of the increment is reduced to capture the physics more precisely.
This technique ensures that the predicted stresses stay within the allowable limits of the material.