Key Issues Review: Numerical studies of turbulence in stars

TL;DR

This review discusses the advances and challenges in numerical 3D simulations of stellar turbulence, highlighting their implications for stellar evolution, supernovae, and nucleosynthesis, and emphasizing the need for improved resolution and physical modeling.

Contribution

It provides a comprehensive overview of recent developments in 3D stellar turbulence simulations, identifying unresolved issues and suggesting directions for future research.

Findings

Core collapse simulations may be under-resolved.

3D effects significantly influence supernova explosion mechanisms.

Current boundary treatments during He-burning need revision.

Abstract

The numerical simulation of turbulence in stars has led to a rich set of possibilities regarding stellar pulsations, asteroseismology, thermonuclear yields, and formation of neutron stars and black holes. The breaking of symmetry by turbulent flow grows in amplitude as collapse is approached, which insures that the conditions at the onset of collapse are not spherical. This lack of spherical symmetry has important implications for the mechanism of explosion and ejected nucleosynthesis products. Numerical resolution of several different types of three--dimensional (3D) stellar simulations are compared; it is suggested that core collapse simulations may be under-resolved. New physical effects which appear in 3D are summarized. Connections between simulations of progenitor explosion and observations of supernova remnants (SNR) are discussed. Present treatment of boundaries, for mixing regions during He--burning, requires revision.