A nonlinear large-deformation analysis of a ring-gear forging simulation is performed with two vertical rezonings (multiple rezonings on a region occurring at different times). Both rezonings use a new mesh. (The new mesh is created using any common meshing software application.)

The forging process is simulated using a 2D axisymmetric model meshed with a 2D four-node structural solid element (PLANE182). The model represents an elastoplastic cylindrical block (the work piece) sitting in a rigid surface (static die).

The block is deformed by another rigid surface (moving die) that moves at an infinitesimal speed, such that the final shape of the work piece becomes a ring gear with complete die fill, as shown in Figure 4.1: Original Finite Element Model with Boundary Conditions and Loading.

The initial analysis diverges due to excessive mesh distortion when 96 percent of the total loading (TIME = 0.96) is reached. The initial rezoning is applied at TIME = 0.716 (substep 26), and the entire work piece is remeshed.

The analysis continues with the new mesh and converges to completion, but the mesh is severely distorted.

A second rezoning is performed at TIME = 0.9 (substep 45), and the entire work piece is remeshed again to ensure proper die fill and more accurate results at TIME = 1.

The results of effective plastic strains and total strains are compared with results of a similar problem.[1]

A single rezoning at a later stage of the analysis may have been sufficient to solve this problem, but the solution described here was chosen instead so that the problem could also demonstrate how vertical rezoning is performed.