On Particle Shifting Techniques (PSTs): Analysis of existing laws and proposition of a convergent and multi-invariant law

• Published in: Journal of computational physics 2022-06, Vol.459, p.110999, Article 110999
• Main Authors: Michel, J., Vergnaud, A., Oger, G., Hermange, C., Le Touzé, D.
• Format: Article
• Language: English
• Subjects: Clustering; Computational physics; Engineering Sciences; Free surfaces; Interpolation; Particle Shifting Technique; Smoothed Particle Hydrodynamics
• ISSN: 0021-9991; 1090-2716
• DOI: 10.1016/j.jcp.2022.110999

•Identification of conditions that should be ensured by a Particle Shifting Technique.•Theoretical study of existing PSTs linked to the targeted list of conditions.•Proposition of an enhanced PST ensuring the targeted conditions.•Validation on 2D and 3D test cases involving free-surface and solid boundaries. This paper addresses the Particle Shifting Technique (PST) in the SPH schemes. Improving the accuracy of SPH schemes leads to particle clustering along the flow streamlines which turns to be detrimental for the simulations. PSTs aim at avoiding this adverse effect by slightly disordering the particles, allowing to retrieve a regular particle distribution within the kernel interpolation support. The gain in accuracy is such that this technique is now commonly adopted by the SPH practitioners, however the conditions that should be respected by a PST are not clearly discussed in the literature. In this paper, such conditions are exposed and their fulfillment by the main existing PSTs of the literature is analyzed. None of these existing PSTs fully satisfying these conditions, a novel PST is introduced. The proposed PST is validated for three different SPH schemes on 2D and 3D test cases, in presence of free-surface and solid boundaries.