Dust deposition over PhotovOltaic (PV) module's surface highly influences the PV module performance and decreases the module output power. This paper studied the particle dust deposition over a tilted PV module under different operating conditions. A combined Eulerian-Lagranigian model was used to model the flow and particle phases. The flow was considered turbulent and the v(2)-f turbulent model was used to predict the air flow characteristics. This study first investigated the air flow characteristics and found the imposed forces on the PV module due to the air flow passed over the module when the module was fixed at different tilt angle as well as different wind directions. Then the particle concentration and deposition over the PV module in the above cited conditions were obtained. Results showed that the maximum particle deposition when the module is faced toward the south occurs at 45 tilt angle for particle larger than 10 gm. This fact does not sustain for smaller particle than 10 gm as in this size the maximum deposition happened in 90 tilt angle. The results also showed that increasing the wind velocity over the PV module increases the corresponding tilt angle for the maximum deposition. (C) 2017 Elsevier Ltd. All rights reserved.