Aerodynamic Characteristics of Transonic Airfoils in Martian Dust-Laden Environments

The Martian rotorcraft represents a key technology for overcoming the exploration limitations of Mars rovers. However, its aerodynamic performance optimization faces formidable challenges in low-Reynolds-number, transonic-speed, and sand-laden two-phase flow coupling environments. Addressing engineering bottlenecks such as low payload capacity and high energy consumption revealed by NASÁs Ingenuity helicopter, this study employs high-fidelity coupled Discrete Phase Model (DPM) and Reynolds-averaged Navier-Stokes (RANS) simulations to investigate the effects of sand particles on the transonic aerodynamic performance of an RAE 2822 airfoil in low-density CO₂ conditions. Utilizing the DDES transition model for turbulence closure and a two-way coupled DPM to resolve momentum exchange, particle injection is controlled via a group-injection scheme. Across Mach numbers from 0.7 to 0.9, comparisons between clean and sand-laden flows of density gradients, velocity fields, boundary-layer thickness, and lift signals reveal shock blunting, boundary-layer thickening, enhanced wake turbulence diffusion, and a marked reduction in lift-to-drag ratio. Findings indicate that increasing particle loading attenuates shock strength and shifts spectral peaks to lower frequencies, with drag increases most pronounced, underscoring the necessity of accounting for gas-particle coupling in the design and flow-control strategies of vehicles operating in sandy planetary atmospheres.