ARCHER is a HighPerformanceComputing code developed at the CORIA laboratory. It stands for Academic Research Code for Hydrodynamic Equations Resolution. It also takes its name from the fish, the Archerfish (Toxotidae), known for preying insects by spitting a jet of water.
Archer is aimed at carrying Direct Numerical Simulations of twophase flows may they be turbulent, incompressible or compressible, with phase change or in presence of solid boundaries. Data from Archer are used for probing the physical properties (either geometrical, morphological, topological, or dynamical) of different phenomena such as atomization, spray formation, dispersion, evaporation, phase separation, capture of solid aerosols. The close connection of the Archer developers with experimentalist is further noticeable. This wide knowledge serves for building or reinforcing physicsinformed models, notably the Eulerian Lagragian Spray Atomization model (ELSA).
It was one of the first code worldwide, undertaking the simulation of liquidjet atomization under a realistic injection configuration.
ARCHER solves on a staggered Cartesian mesh the onefluid formulation of the incompressible NavierStokes equation. In this objective, the convective term is written in conservative form and solved using an improved Rudman’s technique. The latter allows mass and momentum to be transported in a consistent manner thereby enabling flows with large liquid/gas density ratios to be simulated accurately. To ensure incompressibility of the velocity field, a Poisson equation is solved. The latter accounts for the surface tension force and is solved using a MultiGrid preconditioned Conjugate Gradient algorithm (MGCG) coupled with a GhostFluid method. For transporting the interface, use is made of a coupled levelset and volumeoffluid (CLSVOF) solver, in which the levelset function accurately describes the geometric features of the interface (its normal and curvature) and the volumeoffluid function ensures mass conservation. The density is calculated from the volumeoffluid. The dynamic viscosity depends on the sign of the levelset function. In cells containing both a liquid and gas phase, a specific treatment is performed to evaluate the dynamic viscosity. Current work is targeting compressible flow, evaporation, lagrangian particles. ARCHER is written in Fortran+MPI and PyArcher is a Python (Dask+Xarray) library written to pre/post process data for ARCHER. top 

Current major contributers are:
