Workshop: Simulation Cel Explosion In The Depth Of Soil Near A Solid Steel Pipe In Abaqus

In this tutorial, a CEL (Coupled Eulerian-Lagrangian) explosion simulation in Abaqus is performed. The study focuses on an explosion occurring in soil near a buried solid steel pipe.

The Eulerian domain is modeled as a three-dimensional Eulerian part. Air, soil, and TNT are represented as three-dimensional solid parts. The steel pipe is also modeled as a three-dimensional solid part.

Buried pipelines are critical lifelines used for transporting water, gas, and oil. However, pressurized gas pipelines are vulnerable to accidental explosions in process industries, explosives factories, open-pit mines, quarries, and public works. They may also be exposed to intentional explosions, including terrorist attacks. In recent years, several explosions have occurred along oil and gas transmission routes, highlighting the importance of analyzing buried structures under destructive dynamic loads.

To capture the steel pipe behavior under severe loading, elastic-plastic material data is applied. The Johnson-Cook plasticity model, combined with Johnson-Cook damage, is used to simulate pipe failure during detonation.

Air is modeled using the ideal gas equation of state with dynamic viscosity.

Soil is modeled with elastic data and Mohr-Coulomb plasticity.

Explosive (TNT) is modeled using the Jones-Wilkens-Lee (JWL) equation of state. This approach represents the pressure generated by chemical energy release. The programmed burn method is applied, meaning detonation initiation is controlled by geometry and wave speed rather than shock.

A dynamic explicit step is chosen for the analysis. General contact with defined contact properties is applied. Non-reflecting boundaries are assigned to the outer surfaces of the Eulerian domain, while fixed boundary conditions are applied to both ends of the pipe. The volume fraction method defines the location of each material in the Eulerian domain. A fine mesh is recommended to achieve accurate results.

After the simulation, results such as stress, strain, damage, failure, detonation wave propagation, and volume fraction distribution are available. Figures of the results can be reviewed for further analysis.