A wall-modelled large-eddy simulation framework for electrified dust storm turbulence

Abstract

Dust storms are high-Reynolds-number particle-laden turbulent flows in which the turbulent airflow, suspended dust particles and electric fields are strongly coupled. Their multiscale dynamics remains difficult to resolve from field observations alone, which are typically limited to time series at a few wall-normal locations and obtained under uncontrolled environmental conditions. Numerical simulation provides a route to overcome these limitations, but existing models of wind–dust–electric coupling in the atmospheric surface layer (ASL) have rarely been tested systematically against measurements. Here we develop and assess a wall-modelled large-eddy simulation framework for electrified dust storm turbulence. The model represents suspended PM10 dust particles using an advection–diffusion–settling transport equation and includes electric-force-induced drift of charged dust particles. The framework is validated using simultaneous measurements of wind velocity, PM10 dust concentration and vertical electric field at 11 heights from the Qingtu Lake Observation Array. The simulations closely reproduce the observed distributions of wind velocity, dust concentration and electric field, demonstrating the ability of the model to capture coupled wind–dust–electric processes in the ASL. This framework provides a validated numerical tool for investigating multiscale interactions among turbulent structures, dust transport and the electric field in natural high-Reynolds-number dust storms.