Simulation of Accidental LNG Dispersion Free

Regasification terminals act as an emerging risk: even though the technology is rather consolidated, emerging risk issues are evidenced recently; they are mainly related to growing public concerns that are causing serious and spreading local oppositions causing delays or withdrawal of projects that could contribute to a cleaner and more reliable energy supply. Since the ‘70s, experimental campaigns have been carried out on open field releases of dense gases and several modeling tools have been developed. Moreover, being the tests involving the dispersion of heavy gases, such as the Liquefied Natural Gas (LNG), expensive and difficult to carry out, several data come from laboratory tests, such as the wind tunnel ones. The main difficulties encountered in atmospheric dispersion studies in a regasification plant are related to the presence of large obstacles within the area affected by the release of dense gas, which make necessary the use of simulation models developed in the frame of the Computational Fluid Dynamics (CFD). Three-dimensional models have been successfully validated against experimental real scale field data and lab-scale trials, even exploiting the geometries of realistic urban areas. In recent years the amount of scientific publications in this field has been considerably boosted, proof of the interest held by the sector. However, these models involve many input parameters, whose influence on the final result (that is, the hazardous distance from the release point) has not yet fully investigated. Therefore, the main aim of this work was to carry out a sensitivity analysis of the CFD simulation results to some model parameters, such as the heat exchange to the terrain and the equation of state used to represent the released gas behavior.