In March 2009 NFPA published a Model Evaluation Protocol (MEP) for LNG consequence modeling. FLACS is probably the first CFD-tool to complete the MEP.
Until recently NFPA-59A and federal regulations, have required that LNG siting studies are performed using a consequence tool called DEGADIS, developed at the University of Arkansas. This has been convenient for the regulator, as one would expect that a standardized tool would limit the variation in result when comparing different siting studies. NFPA and other players did however gradually acknowledge that a range of other consequence tools existed, and that these may have a better functionality and validity than DEGADIS. In order to open up for other consequence tools, a Model Evaluation Protocol was developed and published at NFPA web-site in March 2009. By passing this MEP, any consequence tool would be considered fit to be used for LNG siting studies.
The LNG MEP consists of 33 different experiments classified either as unobstructed or obstructed:
- Maplin Sands LNG field tests 27, 34 and 35
- Burro LNG field tests 3, 7, 8 and 9
- Coyote LNG field tests 3, 5 and 6
- Falcon LNG field tests 1, 3 and 4
- Thorney Island Freon/N2 field tests 45 and 47
- CHRC CO2 Windtunnel tests A, B and C
- BA-Hamburg SF6 Windtunnel tests (12 tests w/wo obstructions, wind or gravity driven)
- BA-TNO SF6 Windtunnel tests (TUV1, TUV2 and FLS)
Based on reported concentrations at different distances, statistical performance measures (SPMs) are evaluated. FLACS is well within the recommended performance criteria simulating the MEP experiments.