E lmer is an open source multiphysical simulation software developed by CSC. Elmer development was started 1995 in collaboration with Finnish Universities, research institutes and industry.Elmer includes physical models of fluid dynamics, structural mechanics, electromagnetics, heat transfer and acoustics, for example. These are described by partial differential equations which Elmer solves by the Finite Element Method (FEM).As an open source software, Elmer also gives the user the means to modify the existing solution procedures and to develop new solvers for equations of interest to the user. Here are some key features of "Elmer": · Heat transfer: models for conduction, radiation and phase change · Fluid flow: the Navier-Stokes, Stokes and Reynolds equations · Species transport: generic convection-diffusion equation · Elasticity: general elasticity equations, dimensionally reduced models for plates and shells · Acoustics: the Helmholtz equation · Electromagnetism: electrostatics, magnetostatics, induction · Microfluidics: slip conditions, the Poisson-Boltzmann equation · Levelset method: Eulerian free boundary problems · Quantum Mechanics: density functional theory (Kohn-Sham) · Time integration schemes for the first and second order equations · Solution methods for eigenvalue problems · Direct linear system solvers (Lapack & Umfpack) · Iterative Krylov subspace solvers for linear systems · Multigrid solvers (GMG and AMG) for some basic equations · ILU preconditioning of linear systems · Parallelization of iterative methods · The discontinuous Galerkin method · Stabilized finite element formulations, including the methods of residual free bubbles and SUPG · Adaptivity, particularly in 2D · BEM solvers (without multipole acceleration)