A research project has analyzed the dispersion of various gases. The overall objective of the project is to search, identify and prove a gas emitted at a very early stage of a potential vehicle fire in a road tunnel. CFD calculations were used to estimate and illustrate the gas concentration in the road tunnel.

The following image shows H2 as an example. These images show the spatial distribution as a function of time. The initial conditions were obtained through extensive chemical simulations. The study assumes different aeration conditions and gas concentrations. In addition, different gases were considered. A LES (large-eddy simulation) turbulence model was used for the CFD calculations.