Discrete element simulations of self-gravitating rubble pile collisions: the effects of non-uniform particle size and rotation

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Guidos, Job, Kolanz, Lucas, Lazzati, Davide
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909745697259520
author Guidos, Job
Kolanz, Lucas
Lazzati, Davide
author_facet Guidos, Job
Kolanz, Lucas
Lazzati, Davide
contents We present a novel implementation of a soft sphere, discrete elements code to simulate the dynamics of self-gravitating granular materials. The code is used to study the outcome of sub-sonic collisions between self-gravitating rubble piles with masses ranging from $\sim6\times10^{21}$ to $\sim6\times10^{22}$ g. These masses are representative of asteroids and planetesimals in the $\sim100$~km range. We simulate rubble piles composed of a range of particle sizes and analyze the collisions outcome focusing on the properties of the largest surviving fragment. We successfully test and validate the code against previous results. The results of our study show that rubble piles formed by collision of two parent rubble piles do not maintain the same particle size distribution as their parents. Rubble piles formed in low velocity collisions are characterized by a larger fraction of large particles, while the largest fragments of high-velocity collisions show a significant decrease in their mean particle size. We ascribe this effect to the fact that large particles transmit most of the forces during the collisions. In addition, we find that the mass of the largest post-collision fragment does depend on the rotation of the colliding rubble piles. This effect is especially noticeable when the pre-collision spin axes are parallel with each other and perpendicular to the relative velocity. This finding can be particularly relevant for meter to kilometer sized bodies embedded in protostellar accretion disks, where viscous stresses can efficiently align the target and projectile spin axes.
format Preprint
id arxiv_https___arxiv_org_abs_2410_22189
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Discrete element simulations of self-gravitating rubble pile collisions: the effects of non-uniform particle size and rotation
Guidos, Job
Kolanz, Lucas
Lazzati, Davide
Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
We present a novel implementation of a soft sphere, discrete elements code to simulate the dynamics of self-gravitating granular materials. The code is used to study the outcome of sub-sonic collisions between self-gravitating rubble piles with masses ranging from $\sim6\times10^{21}$ to $\sim6\times10^{22}$ g. These masses are representative of asteroids and planetesimals in the $\sim100$~km range. We simulate rubble piles composed of a range of particle sizes and analyze the collisions outcome focusing on the properties of the largest surviving fragment. We successfully test and validate the code against previous results. The results of our study show that rubble piles formed by collision of two parent rubble piles do not maintain the same particle size distribution as their parents. Rubble piles formed in low velocity collisions are characterized by a larger fraction of large particles, while the largest fragments of high-velocity collisions show a significant decrease in their mean particle size. We ascribe this effect to the fact that large particles transmit most of the forces during the collisions. In addition, we find that the mass of the largest post-collision fragment does depend on the rotation of the colliding rubble piles. This effect is especially noticeable when the pre-collision spin axes are parallel with each other and perpendicular to the relative velocity. This finding can be particularly relevant for meter to kilometer sized bodies embedded in protostellar accretion disks, where viscous stresses can efficiently align the target and projectile spin axes.
title Discrete element simulations of self-gravitating rubble pile collisions: the effects of non-uniform particle size and rotation
topic Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2410.22189