Effect of dust on the performance of wind turbines

An experimental investigation on the effect of blade surface roughness, due to dust accumulation, on the performance of wind turbines was performed. The development of the energy generating costs of wind turbines directly depends on the wind turbine output, which depends upon the characteristics of the turbine blades and their surface roughness. An important operating requirement that relates to a wind turbines airfoils are its ability to perform when the smoothness of its surface has been degraded by the dust. The effect of surface roughness of rotor blades due to accumulated dust on the blade surface of stall-regulated, horizontal axis 300 kW wind turbine was investigated. The mechanism of dust built up and accumulation on the blade surface of wind turbine was investigated, and the effect of operation period of wind turbine on the blade surface roughness intensity was investigated experimentally. Also, the quantity of dust accumulated on the blade leading edge; and the effect of changing dust area on blade surface were studied. Standard roughness in Hurghada site was chosen and put in various leading edge areas. The roughness area on blades was changed from 5 to 20% from the chord line towards the leading edge. The effect of dust on the performance of pitch-regulated 100 kW horizontal axis wind turbine was investigated. These results from pitch-regulated wind turbine were compared with 100 kW stall-regulated wind turbine.