# Effect of gravity on clustering patterns and inertial particle attractors in Kinematic Simulation

## TL;DR

This study investigates how gravity influences the clustering patterns and attractors of inertial particles in a kinematic simulation, revealing how attractor dimensions and positions vary with particle inertia and gravity effects.

## Contribution

It introduces a systematic Lagrangian tracking method to identify and quantify particle clustering attractors under varying gravity and inertia conditions.

## Key findings

- Attractor dimensions vary from 3D to 1D depending on gravity and inertia.
- Gravity shifts attractors from horizontal to vertical positions.
- Clustering patterns depend on Stokes and Froude numbers.

## Abstract

In this paper, we study the clustering of inertial particles using a periodic kinematic simulation. The systematic Lagrangian tracking of particles makes it possible to identify the particles' clustering patterns for different values of particle inertia and drift velocity. The different cases are characterised by different pairs of Stokes number $St$ and Froude number $Fr$. For the present study $0\leq St \leq 1$ and {$0.4 \leq Fr \leq 1.4$}. The main focus is to identify and then quantify the clustering attractor - when it exists - that is the set of points in the physical space where the particles settle when time goes to infinity. Depending on gravity effect and inertia values, the Lagrangian attractor can have different dimensions varying from the initial three-dimensional space to two-dimensional layers and one-dimensional attractors that can be shifted from a horizontal to a vertical position.