Comparison of Wind Speed-Up over Escarpments Derived from Numerical Modeling and Wind-Loading Codes

Document Type : Research Article

Authors

Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin, Iran

Abstract

The most common lateral load is a wind load. The wind speed profile considers as an effective parameter to find the wind load. Topographic features such as escarpments and hills in flat area can significantly amplify wind speeds near the ground. The main aim of this study is to investigate the effects of the escarpment characteristics on the velocity profile and speed-up using the numerical model. At the first, the numerical model validated with the experimental results obtained through the wind tunnel of Texas University. Then, three kinds of escarpments with different slopes simulated and speed-ups obtained from the numerical model, wind tunnel, ASCE and Iran codes compared. The results of numerical model at the smaller slope showed better accordance with wind tunnel results. The effect of inlet velocity profile on the speed-up was numerically studied. Comparison of the results showed that the maximum speed-up using the velocity profile of Iran code is greater than using ASCE code. Finally, the effect of the escarpment height and width with the same slope on speed-up was investigated. The results showed that speed-up grows as the width and height increase; however, the effect of increasing the height is less.

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