For more than 30 years, the team at GexCon has been one of the leading institutions for safety related gas explosion research in the oil and gas industry. We have not only pioneered the understanding of how objects and obstructions may play a crucial in flame acceleration, but also the understanding of how confinement and venting may influence explosion overpressures. GexCon has extensively studied and evaluated the effects of various factors on the dynamics of an explosion, which include: different fuel types, mixtures of different gases, gas concentrations, ignition locations, mitigation (deluge), and aerosols. The CFD-software FLACS was developed in parallel with experimental research projects and has developed into a leading tool for CFD explosion modeling studies involving gas explosions. The example below shows how flame accelerations can generate high overpressures and external blast waves in a typical industry facility. The resulting explosion modeling demonstrates how external blast pattern can be far from symmetric.
Based on the significant R&D and software validation efforts, FLACS can be expected to give accurate predictions for a wide range of cases when simulation guidelines are followed. FLACS is widely used in the oil and gas industry and is, in fact, required by some companies to evaluate facility designs against expected explosion and blast loads.
The above are examples on how objects and obstructions can influence flame acceleration. The two equivalent volumes have arrays of pipes that block 50% of the available volume and both are filled with stoichiometric propane. When igniting in the corner, the geometry with many small repeated pipes produced overpressures 100 times higher than the case with fewer, but larger pipes.
For more information regarding recent explosion studies and explosion modeling using FLACS:
- Davis, S.G., Engel, D., Gavelli, F., Hinze, P., and Hansen, O.R., Advanced Methods for Determining the Origin of Vapor Cloud Explosions Case Study: 2006 Danvers Explosion Investigation, Paper presented at ISFI meeting, Hyattsville, USA, Sept 27-29, 2010.
- Davis, S.G., Hinze, P., Hansen, O.R., and van Wingerden, K., Investigation Techniques used to Determine the Massive Vapor Cloud Explosion at the Buncefield Fuel Depot, Paper presented at ISFI meeting, Hyattsville, USA, Sept 27-29, 2010.
- Hansen, O.R., Hinze, P., Engel, D., and Davis S.G., Using CFD for Blast Wave Predictions, Presented at the Mary Kay O'Connor Process Safety Symposium, College Station, USA, Oct. 27-28, 2009.