Analysis and zoning of wind energy based on sand drift potential in Qom-Tehran railway

Due to vast desert area in Iran, wind regime studies are important for the railway safe design as well as aeolian sediment transport. In this study wind regime and sand drift potential (DP) were calculated with Fryberger method in nine meteorological stations located near to the Qom –Tehran railway (178 km). For this reason, hourly wind speed and direction data were analyzed. Annual wind roses showed that West and Northwest winds were predominantly about 40%, 50%, 42% and 57% at the stations of Tehran, Shahriyar, Qom, and Imam Khomeini airport, respectively.  The highest amount of sand drift potential was at the Imam Airport station (DP= 574, UDI=0.8) in the west and its lowest value was at Qom station (DP= 109, UDI= 0.47) in the south of the region. The drift potential (DP) for aeolian deposits was generally high (DP >400) in the Garmsar (DP= 481), Salafchegan (DP= 485), Saveh (DP= 552) and Imam Khomini airport (DP=574) climatological stations. DP was relatively moderate (200>DP>400) at the Shariyar and Kahak stations in the northwest and south of study area, respectively; and weak (DP<200) in the Tehran and Qom climatological stations.  There was an increasing trend in the transport of sand when moving from Namakzar railway station to the Imam Khomeini railway station. Also field evaluations indicated the sensitivity of the Separ Rostam-Namakzar block to entry of sand, which was 21.3 kilometers long. Finally, it is suggested to railway directors of the Islamic Republic of Iran to proceed with the assessment of sand drift potential near railways station for control of sand deposition.