Airbus Defence and Space



The integrated Environment package contains all applications that use a set of standard environment models gathered in a common library.

An associated visualization module access to the environment models library for displaying key parameters such as atmosphere components, particle fluxes along orbits…


Envipack detailed presentation


Features / Technical Details

DOSRAD is the application dedicated to the optimal shielding design against total dose accumulation. This 3D numerical tool is intended for :

  • Equivalent thickness of structure shielding and total dose computation at equipment level with mesh refinement,
  • Total dose computation at component level.

DOSRAD is based on a ray-tracing method and performs an efficient solid angle sectoring analysis.

MATCHARGE is the solar cell degradation tool (1 MeV damage equivalent electron fluences) for exposure to proton and electron radiations. All types of cells (mono- and multi-junction) can be simulated through damage ratio externally introduced by the user.

OUTGASSING is the software computing the time evolution of deposits of contaminants (that outgas from spacecraft surfaces). The main assumption is that the flow regime in the outgassing cloud is free molecular (only few collisions). Then, the molecules are supposed to move following lines between the surfaces.

The first calculation step is the computation of the mass transfer factors, i.e. the proportion of the total mass emitted by a surface node i and reaching a surface node j. This is performed using efficient ray-tracing and Monte-Carlo methods.

Direct flux, flux scattered by other contaminant molecules (self-scattering), flux scattered by ambient gas flux (ambient scattering), and flux re-emitted from spacecraft surfaces are added.

The second step is the time computation of both the emitted contaminant mass and its deposit on the spacecraft surfaces taking into account surface re-emission. This key step requires a precise knowledge of material property data, i.e. reference time constants of the emission and reemission laws, percentage of the total mass material that can outgas…

Results are mass on surface nodes as a function of time. They can be visualized on the 3D geometry or plotted on outgassing curves.

ATOMOX is the 3D geometrical analysis tool for the computation of atomic oxygen –AO– (and other species of the residual atmosphere) fluence and resulting material erosion on the outer surfaces of an orbiting spacecraft in low Earth orbit.

It accounts for the 3D spacecraft geometry, the spacecraft attitude, surface material properties (e.g. absorptivity, diffuse / specular reflection) and computes the species fluence for the mission lifetime. The main directional properties of the incident particles are included: motion through the co-rotating atmosphere, shadowing brought by the structure, particles thermal motion and multiple reflections on the external surfaces. Standard atmosphere models can be selected for the computation of the particles number density.


DOSRAD and MATCHARGE are being used routinely in Airbus Defence and Space for radiation assessment on many space projects of telecommunication, earth observation and science.

OUTGASSING is mainly used on sensitive satellites dedicated to the Earth observation or scientific missions. It is used to predict the contamination of the external surfaces and around the spacecraft, or the internal part of sensitive instruments (telescopes).

ATOMOX is often used to perform prediction of surfaces recession on LEO Airbus Defence and Space spacecraft. The maturity of the tool is good, as the process of surfaces erosion by Atomic Oxygen is well understood and as the materials sensitivity to AO has been measured for most of the space materials. Moreover dedicated validations have been performed on LDEF spacecraft showing a good agreement between simulation and in-orbit data.

Reference customers