Efficient and Accurate Adaptive Resolution for Weakly-Compressible SPH

TL;DR

This paper introduces an efficient adaptive resolution method for weakly-compressible SPH that dynamically adjusts particle resolution, reducing computational cost while maintaining high accuracy in fluid simulations.

Contribution

The paper presents a novel adaptive resolution technique for SPH that ensures optimal neighbor counts and reduces particle numbers by up to 250 times compared to existing methods.

Findings

Accurate simulation of flow past a cylinder at various Reynolds numbers.

Significant reduction in particle count while maintaining accuracy.

Method is fully parallel and automatically adapts to moving solids.

Abstract

In this paper we propose an accurate, and computationally efficient method for incorporating adaptive spatial resolution into weakly-compressible Smoothed Particle Hydrodynamics (SPH) schemes. Particles are adaptively split and merged in an accurate manner. Critically, the method ensures that the number of neighbors of each particle is optimal, leading to an efficient algorithm. A set of background particles is used to specify either geometry-based spatial resolution, where the resolution is a function of distance to a solid body, or solution-based adaptive resolution, where the resolution is a function of the computed solution. This allows us to simulate problems using particles having length variations of the order of 1:250 with much fewer particles than currently reported with other techniques. The method is designed to automatically adapt when any solid bodies move. The algorithms employed are fully parallel. We consider a suite of benchmark problems to demonstrate the accuracy of the approach. We then consider the classic problem of the flow past a circular cylinder at a range of Reynolds numbers and show that the proposed method produces accurate results with a significantly reduced number of particles. We provide an open source implementation and a fully reproducible manuscript.