We tested the adequacy of using the lattice Boltzmann method (LBM) as an alternative to Eulerian or Lagrangian methods in river oil spill modelling. By using simpler sets of partial differential equations, derived with the discretisation of the Boltzmann Bhatnagar-Gross-Krook (BGK) equation, the LBM model is able to achieve higher computational efficiency than the established models. The newly developed LBM model is a general model that can be used to simulate the transport of oil in rivers and seas. It was validated on the 2006 Lebanon oil spill case using a two-dimensional two-relaxation-time D2Q9 model; and by comparing three-dimensional D3Q7 Zhou model results to the results of the Nafta3D model for a river oil spill. After the reliability of the results of the LBM model was confirmed, the next step was to determine whether the LBM model is equivalent to or possibly, as hypothesised, better than existing models. The efficiency of the model was tested in two phases. In the first phase, more than 1400 different simulations were carried out to assess the efficiency of the methods without taking into account the effect of the calculation domain on the calculation time. The D2Q9 LBM model was on average eight times faster than existing models while maintaining the same level of accuracy. In the second phase, we discovered that the shape of the calculation domain does not have any significant impact on the calculation time, thus fully confirming our initial hypothesis. In an actual oil spill event, the use of the LBM can result in significantly shorter calculation times, which can contribute significantly to reducing the consequences of pollution. The new model has proved to be a valuable tool in this area and can therefore be recommended for use in real oil spill events.
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