Mourad Heniche

As part of the environment of the St-Lawrence River, the Canadian Coast Guard team and the URPEI research team at Ecole Polytechnique de Montreal carried out a numerical simulation based on the Eulerian-Lagrangian formulation for the dispersion of oil-mineral aggregates (OMA) in a turbulent flow produced by a propeller ship. This study is part of a larger project to assess the effectiveness of using fine clay minerals as a natural dispersant of petroleum in ice. The interest is to study the effect of an ice cover on the dispersal potential of a typical winter flow field. To highlight the potential dispersion, two hydrodynamic scenarios are chosen, with and without the presence of an ice cover. For each scenario, the calculation results are presented for a selection of particle densities in order to assess the model by comparison of the OMA distribution statistics in the water column.

It is well known that residence time distribution (RTD) is a significant parameter in material processing, therefore, its accurate prediction is essential. From a numerical standpoint, one of the most widespread simulation methodologies is based on the combination of computational fluid dynamics (CFD) and particle tracking techniques. Within this framework, the novelty of this contribution is that the RTD is built upon a minimization of a least square criterion ensuring an accurate prediction of the mean residence time, as well as a smooth RTD function. In addition, a computational procedure is developed to estimate the thickness of the near‐wall region, which must be free of particles otherwise the RTD predictions will diverge. The relevance of the proposed method is assessed on analytical flow test cases and the Kenics static mixer for both Newtonian and non‐Newtonian fluids. Good agreement is found between numerical and corresponding theoretical mean residence times. magnified image