(197b) Comparison of Lng Computational Fluid Dynamics Consequence Modeling with Brayton Field Fire School Test Data – Preliminary Assessment

Complex scenarios increase the demand of Computational Fluids Dynamics (CFD) modeling. Either explosion or gas dispersion, CFD consequence modeling has become an inevitable tool to predict effect of a release. Passive barrier such as dike, containment pit, and vapor barrier have been recommended to be used in order to control LNG release on land and its associated LNG spreading, vapor dispersion, and pool fire. Because of limited LNG field experimental data, the effectiveness of these barriers and its proper CFD application are not well understood therefore they are not used efficiently. The combination of CFD modeling and field test could reduce the uncertainties associated with passive barriers and advance the industry to a better understanding of passive barriers or other mean of mitigations.

BP technology and Mary O'Connor Process Safety Center has joined together in a program to study LNG hazards and mitigation systems for LNG vapor. This program is to study vapor dispersion modeling using CFD model and perform LNG field experiment at the Texas A&M University's Brayton fire school.

The paper presents the result of LNG field tests and its associated CFD modeling. LNG field experiment results on 22 ft by 33 ft and 4ft deep containment pit is described. An extra four feet wall added as an obstacle to the vapor cloud. Two scenarios were developed in this pit for LNG spill on water and spill in the concrete. Gas concentration and temperature is recorded to be compared with CFD simulation. CFD simulation is useful because of the shape of the wall and the depth of the pit. Both scenarios have important information that are incorporated into LNG flow rate, transient evaporation rate, level of LNG in the pit, or pool formation onto water surface with higher evaporation rate.