*Result*: Mechanisms Controlling Dust Aerosol Collection by Isolated Obstacles Near the Ground.

*The collection of dust aerosols (0.1–10 μ ${\upmu }$m) by near‐surface obstacles is one of the important processes in atmospheric aerosol dry deposition. However, existing understanding of this process remains limited. For example, most current deposition models assume complete deposition or describe the collection process through empirical models, making it difficult to accurately predict the concentration distribution of dust particles within the near‐surface collection layer. In this study, the effects of turbulence around obstacles are considered to improve an existing numerical model for simulating aerosol particle deposition in rough surface environments. The modified numerical model is validated through wind tunnel experiments. Subsequently, the particle collection process on an isolated cylindrical obstacle placed on the ground is investigated using numerical simulations. The effects of different wind conditions, particle properties, and obstacle sizes on the collection process are analyzed. Finally, a fitted relationship between the Stokes number and collection efficiency is proposed. The results show that inertial impaction and interception jointly dominate particle deposition on the windward side of the isolated obstacle, while turbulence‐induced impaction governs deposition on the leeward side. Therefore, parameters that affect particle inertia and the turbulent flow around the obstacle have a more significant impact on the particle deposition process. The simulation results agree well with existing experimental data and exhibit lower data dispersion, demonstrating that the numerical model developed in this study can effectively describe the collection of particles by near‐surface obstacles. This provides a solid basis for improving atmospheric particle deposition models. Plain Language Summary: When dust aerosols (0.1–10 μ ${\upmu }$m) approach the ground, they can be retained by various ground objects. This process is of pivotal importance in the removal of dust aerosols from the atmosphere. However, the scientific community's understanding of the interactions between these particles and ground surfaces remains limited. Consequently, it is challenging to predict the concentration distribution of particles that will settle in close proximity to the ground. To address this issue, this study improved a numerical model to simulate the process of particle deposition on the surface of a single cylindrical object placed on the ground. Our research results indicate that the ease of particle deposition is closely related to the particles' capacity to resist changes in motion (inertia) and the flow characteristics of the air around the object. The model shows high consistency with experimental data from other studies and provides higher data quality. This makes it a useful tool for improving predictions of how particles settle near the ground, which can support environmental research and air quality modeling. Key Points: Turbulence around near‐ground obstacles significantly affects the deposition of airborne dust aerosol particlesParticle size, wind speed, and obstacle dimensions jointly influence particle collection efficiencyThe improved model predicts particle deposition on near‐ground obstacle surfaces with higher accuracy [ABSTRACT FROM AUTHOR]

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