Enhanced ALE data transfer strategy for explicit and implicit thermomechanical simulations of high-speed processes

The Arbitrary Lagrangian Eulerian (ALE) formalism, which allows the computational grid to move regardless of the material deformation, is a convenient way to avoid distorted meshes in finite element simulations. One crucial step of the ALE algorithm is the data transfer between the Lagrangian and the Eulerian meshes. In this paper, an enhanced transfer method is presented. It can handle complex finite elements which are integrated with more than one Gauss point. This method can thus be used either with an explicit or with an implicit time integration scheme. Choosing the adequate order of accuracy and the most appropriate number of physical fields to be transferred is always a compromise between the speed and the precision of the model. For example, some variables may be sometimes ignored during the transfer in order to decrease the CPU time. Therefore, the most effective way to use such an algorithm is demonstrated in this work by revisiting a classical ALE benchmark, the Taylor impact. An implicit thermomechanical ALE simulation of a high-speed tensile test is also presented and is compared to experimental results from the literature.

► This paper presents an efficient data transfer method in the frame of the Arbitrary Lagrangian Eulerian formalism. ► This method is first or second order accurate and can handle more than one Gauss point per element. ► The influence of the nodal velocity transfer is studied in the case of the explicit Taylor bar impact benchmark. ► An implicit thermomechanical model of the Hopkinson bar is modelled and compared to results from literature.