CFD Dispersion Investigation of CO2 Worst Case Scenarios Including Terrain and Release Effects

In the present paper, CFD (computational fluid dynamics) computations were performed in order to get insight in heavy gas dispersion behavior based on experimental results and extrapolate them to a representative full bore rupture scenario of a CO2 pipeline. The impact of the release process is investigated on the overall heavy gas dispersion. The study focuses on the importance of an accurate source term modeling by means of the numerical rebuilding of experimental data from wind tunnel and full scale; a representative 2-phase release model with low numerical effort is developed. Different full scale CO2 pipeline rupture release scenarios are simulated including a representative terrain topology. Wind conditions and shut-in valve distances are varied resulting in a strong interaction of the released heavy gas with the turbulence of the atmospheric boundary layer but also the terrain topology. Based on these results it can be stated that effect distances are locally increased drastically, also with respect to their temporal behavior