Europlexus, or short EPX, is a simulation software dedicated to the analysis of fast transient phenomena involving structures and fluids in interaction. The program is co-owned by the French Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA) and the Joint Research Centre of the European Commission (EC/JRC).
EPX is based on a space discretization by means of Finite Elements, SPH Particles (Smooth Particle Hydrodynamics) or Discrete Elements for structures, or by means of Finite Elements, Finite Volumes or SPH Particles for fluids. Time integration is achieved through a conditionally stable explicit scheme. The solving algorithm is completely non-linear, at both geometric level (large displacements; large rotations) and material level (constitutive laws implementing plasticity or damage for example).
The programme provides a large number of kinematic links between entities, for instance for boundary conditions, contact between structures or fluid-structure interaction.
EPX implements specific models able to analyse various mechanical situations, such as shocks, impacts, explosions, wave propagations and their consequences on structures.