Comparing the Effect of Radiative Transfer Schemes on Convection Simulations

TL;DR

This study compares two radiative transfer schemes in 3D stellar convection simulations, revealing how different methods influence the thermal structure of the superadiabatic layer and atmosphere.

Contribution

It introduces a direct comparison of two fundamentally different radiative transfer schemes in stellar convection simulations, highlighting their impact on thermal properties.

Findings

Simulations agree broadly but differ in superadiabatic layer structure.

Radiative transfer method affects thermal stratification.

Differences are notable in the atmosphere's thermal profile.

Abstract

We examine the effect of different radiative transfer schemes on the properties of 3D simulations of near-surface stellar convection in the superadiabatic layer, where energy transport transitions from fully convective to fully radiative. We employ two radiative transfer schemes that fundamentally differ in the way they cover the 3D domain. The first solver approximates domain coverage with moments, while the second solver samples the 3D domain with ray integrations. By comparing simulations that differ only in their respective radiative transfer methods, we are able to isolate the effect that radiative efficiency has on the structure of the superadiabatic layer. We find the simulations to be in good general agreement, but they show distinct differences in the thermal structure in the superadiabatic layer and atmosphere.