Sloshing
Technical Bulletin 2013

BV methodology (BV NI554, “Design Sloshing Loads for LNG Membrane Tanks “) for sloshing loads determination is decomposed in three main steps (seakeeping analysis, Computational Fluid Dynamics calculations and sloshing tests) which are standard parts of BV comprehensive sloshing assessment. All these steps are subject of research and developments efforts. First, advanced seakeeping analyses regarding FLNG systems (side-by-side operations, gap resonance) are presented (Hydrodynamics section). Second, a new post-processing tool (BV plug-in developed within OpenFOAM) for CFD calculations is presented. This post-processing tool provides precise information on the most severe impacts’ locations without any restriction like those encountered during sloshing model tests. It opens some new interesting horizons for cargo containment systems optimization and for careful and safe operations. Third, sloshing model tests and their statistical post-processing are also tackled. Through participation to ISOPE Sloshing Benchmark, BV participates to the establishment of best practices for sloshing tests. Finally, statistical post-processing - which is one of the most critical steps of sloshing assessment – is subject of two papers. The first one presents a synthesis of the statistical behaviours of all sloshing key parameters (global and local) and concludes (as expected) to the highest variability of sloshing pressures. Finally, Extreme Value Theory is applied to these sloshing pressure samples in order to improve models used for predicting sloshing pressure maxima.

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