Modeling the Two-Phase Flow Field beneath a Hovering Rotor on Graphics Processing Units Using a Hybrid Vortex/CFD Methodology

Abstract

The particle-laden flow field beneath a hovering microrotor is simulated using a hybrid free-vortex method/unsteady Reynolds-averaged Navier-Stokes (FVM-URANS) solver coupled with a Lagrangian sediment-tracking algorithm. The present work attempts to examine the capabilities of a high-fidelity computational fluid dynamics analysis together with a sediment-tracking algorithm to analyze the evolution of brownout clouds. Both the single-phase and dual-phase flow fields are simulated and compared to available experimental data. The variation of the phenomenological attributes of the cloud evolution as a function of particle size was analyzed and found to agree with experimental evidence. To enable single-desktop simulations, all components of this methodology are designed to run on double-precision, programmable graphics processing units. This hybrid implementation uses a multigranular, parallel approach to demonstrate significant performance gains over equivalent single-core central processing unit simulations.