Large-Eddy Simulation of Titan’s near-surface atmosphere: Convective turbulence and flow over dunes with application to Huygens and Dragonfly

Abstract

Abstract The planetary boundary layer (PBL) on Titan is modeled using large-eddy simulation (LES) to quantify the turbulence structures and statistics in the atmospheric surface layer. The results at three different stability states over a flat surface indicate similar velocity fluctuations to the limited observations taken by the Huygens probe during descent, and are much weaker than those characteristic of the convective PBL on Earth and Mars. Additionally, turbulence statistics are calculated using topographical configurations representative of Titan’s dunes, thereby quantifying the acceleration of the mean flow over the dune crest. The resolution available with the LES are relevant for future science missions to Titan, including the Dragonfly rotorcraft lander recently selected for the NASA New Frontiers program.