Isale tillotson eos code#
Isale tillotson eos free#

We illustrate the paucity of disruptive collisions between major bodies, as compared to collisions between less massive planetesimals in late-stage planet formation, and thus focus on more probable, low-velocity collisions, though our relations remain relevant to disruptive collisions as well.

The accuracy of these relations is also comparable to the deviations of results between different SPH codes and initial thermal/rotational conditions. These are fast, easily coded relationships based on a large database of smoothed particle hydrodynamics (SPH) simulations of collisions between bodies of different compositions, including those that are water rich. We develop empirical relationships for the accretion and erosion of colliding gravity-dominated bodies of various compositions under conditions expected in late-stage solar system formation.

Isale tillotson eos free#

We attribute this difference to a fundamental difference in thermodynamic behavior of silicate melts captured by the hard‐sphere EoS and by newly proposed EoSs in the hard‐sphere model of silicate melts, configurational entropy dominates in free energy, whereas in the newly proposed model, entropy is dominated by vibrational entropy similar to entropy of solids. Similarly, two recently proposed EoSs have small effects on the composition of the disk in comparison to the model where the hard‐sphere EoS is used for preexisting magma ocean. We found that changing the EoS for solids from Tillotson to M‐ANEOS EoS resolves the issues of latent heat, but its effect on the composition of the disk is small compared to the influence of the hard‐sphere EoS of magma ocean in controlling the composition of the disk. The goal is to investigate to what extent we can explain the observed composition of the Moon including the similarity in the isotopic composition and the dissimilarity in the FeO/(FeO + MgO) ratio as compared to that of Earth by the different types of EoS assuming the conventional collision conditions. (2019), is improved by replacing the EoS of the solid from Tillotson EoS to M‐ANEOS, and we also explored two recently proposed EoSs by Stewart et al. A limitation in our previous model Hosono et al. These results will inform the LICIACube ejecta cone analysis.We explore the role of various equations of state (EoS) in controlling the composition of the Moon formed by a giant impact (GI) using a density‐independent SPH code. The most prominent effects of projectile geometry are seen in the ejection velocity as a function of launch position and ejection angle of the fast ejecta that resides in the so-called ‘coupling zone’. The momentum enhancement factor in these test cases, commonly referred to as β, was within 7% for the 2D simulations and within 10% for the 3D simulations, of the value obtained for a uniform spherical projectile. In the case of a more extreme projectile geometry (i.e., a rod, modelled in three-dimensions), the crater was elliptical and 50% shallower compared to the crater produced by a spherical projectile of the same momentum. Projectile geometries modelled in two-dimensions that have similar surface areas at the point of impact, affect the crater radius and the crater volume by less than 5%. We found that the simple projectile geometries investigated here have minimal effects on the crater morphology and momentum enhancement.

Isale tillotson eos code#

To investigate the effects of alternative, simple projectile geometries on the DART impact outcome we used the iSALE shock physics code in two and thee-dimensions to model vertical impacts of projectiles with a mass and speed equivalent to the nominal DART impact, into porous basalt targets. For simplicity, most previous numerical simulations of the impact used a spherical projectile geometry to model the DART spacecraft. The DART spacecraft will impact Didymos’s secondary, Dimorphos, at the end of 2022 and cause a change in the orbital period of the secondary.