When simulating an incompressible fluid, traditional weakly compressible SPH techniques have disadvantages includ- ing noisy pressure predictions and high computational costs. As an alternative, incompressible SPH simulations can be achieved by employing a projection method to enforce a divergence free velocity field. Such techniques are receiving considerable interest in the literature due to the potential for noise free pressure predictions, with acceptable computational costs. The method does however suffer from stability issues when particles bunch together or are stretched apart from one another, which is generally the case if particles are restricted to following streamlines, as is dictated by the Navier-Stokes equations. To overcome this issue, particles can be shifted away from one another, across streamlines, according to some algorithm whose job it is to determine a suitable displacement vector. The primitive variables are then corrected to account for their change in position via interpolation.Here, we follow on from earlier work in the authors’ group and employ Ficks’s law to shift the particles. We present validation cases involving cylinder and wedge slamming into initially calm water. We also consider cylinder exit from initially calm water. These cases are particularly relevant to the design of ships and wave energy extraction devices. The results we present show effectively noise free pressures and very high accuracy. To our knowledge, this is the first time such accuracy has been achieved via SPH techniques for such complex cases.
|Title of host publication||host publication|
|Publication status||Published - May 2012|
|Event||7th international SPHERIC workshop - Prato, Italy|
Duration: 29 May 2012 → 31 May 2012
|Conference||7th international SPHERIC workshop|
|Period||29/05/12 → 31/05/12|