Airborne dust effect on soiling dynamics of inclined photovoltaic panels for low wind speed and no particle resuspension conditions

The performance of photovoltaic (PV) panels is strongly affected by dust accumulation, requiring a clear understanding of deposition mechanisms. Recent advances in nanotechnology and surface science are increasingly supporting mitigation strategies for this challenge. Under no particle bouncing conditions, and fixed simulation time, 10 sec., this study investigates the effects of panel inclination angle, low wind speeds (≤ 2 m/s), and particle diameter on dust deposition behavior on PV surfaces. Results show that increasing the inclination angle raises the critical sliding velocity while reducing resistance to lift-off due to decreased normal loading. Particle size plays a dominant role in deposition dynamics, where larger particles ≥ 25 μm consistently deposit due to stronger gravitational and aerodynamic forces, while smaller particles exhibit a gradual size-dependent increase in deposition probability. Deposition distance and surface coverage increase with particle diameter, indicating stronger fouling by coarse particles. Mean deposition time decreases with increasing particle size and wind speed. Increasing wind speed enhances deposition rate and surface coverage, while having limited effect on the fraction of deposited particles under the no-bouncing assumption. The influence of inclination angle on deposition metrics is relatively weak under fixed particle size and wind conditions. Overall, deposition rate increases with particle size but decreases with increasing inclination angle, highlighting the importance of optimizing panel tilt to mitigate dust accumulation and improve PV performance.