PRINCIPIA, TECHNIP and CYBERNETIX will give collectively a lecture at the 17th International workshop on trends in numerical and physical modeling for industrial multiphase flows

“Experimental qualification of a CFD model for simulation of LNG spillage on solid structures”

ABSTRACT

LNG (Liquefied Natural Gas) accidental cryogenic spillage is one of the major safety concerns of the new Floating LNG facilities. Many critical elements like primary structures, deck and equipment supports shall be properly protected against these hazards, using very costly and constraining passive cryogenic spill protection materials, thus requiring optimization efforts.

A LNG leak, originated for instance from a pipe rupture, involves very complex physical phenomena, more particularly:

 Cryogenic liquid jet fragmentation, vaporization, flashing, rainout.

 Cryogenic liquid pool formation, spreading, vaporization.

 Thermal transfer with solid and liquid substrates.

CFD approach is deemed to be the most efficient and accurate way to simulate the overall behaviour of the release. In the frame of a Joint Industry Project the 3D CFD software EOLE capabilities, developed by Principia, have been extended to LNG leak simulation. The CFD code is based on an Unsteady Reynolds Averaged Navier-Stokes (URANS) model using coupled Volume of Fluid (VOF) and mixture models, which allows simulation of all dynamic / thermodynamic processes of LNG multi-phases flows, i.e. most of the physics of accidental cryogenic leaks that may occur in FLNG topsides.

The software has been validated based on mid-scale experiments with liquid nitrogen performed by Technip at its Cybernetix cryogenic testing facilities in France.

The experimental protocol addressed the different physical mechanisms described above, especially flashing jets, pool spreading and physical phenomena at liquid/solid and liquid/water interface (thermal transfer, vaporisation, boiling curve).