Document Type : Original Article

Authors

1 Department of Biosystem Engineering, University of Tehran, Tehran, Iran.

2 Department of Mechanical Engineering of Biosystems, Shahrood University of Technology, Shahrood, Iran.

3 Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran.

Abstract

The use of ducted wind turbines is developing and various scientists in their studies investigate the performance, economic analysis, and energy production by these types of turbines at a lower cost. In this paper, the ratio of wind speed increment related to free stream wind speed and turbulence rate in a pre-designed duct used for a horizontal three-blade wind turbine was evaluated using a hot-wire anemometer sensor and data analysis methods. The duct installed in the University of Tehran Aerospace Faculty wind tunnel and flow characterization was performed by using CTA apparatus to measure and evaluate the wind flow turbulence in the throat section of the duct, where the wind turbine was installed. Wind speed analysis was done at different speed of the wind tunnel test section and shown that in the throat section of the duct the wind speed increased with a constant slope and in more analysis, it was found the wind speed in the duct throat can be increased to 2.5 up to 3 times of free stream flow speed at a different wind speed of wind tunnel test section. From spectral analysis, it was found that only a few peaks are included in the extracted frequency that shown low turbulence inside the duct it can be concluded that the flow disturbances will not have a significant impact on the performance of the wind turbine placed inside the duct throat.

Keywords

[1] Allaei, D., Tarnowski, D., and Andreopoulos, Y. (2015). INVELOX with multiple wind turbine generator systems. Energy, 93, 1030–1040. https://doi.org/10.1016/j.energy.2015.09.076.
[2] Han, W., Yan, P., Han, W., and He, Y. (2015). Design of wind turbines with shroud and lobed ejectors for efficient utilization of low-grade wind energy. Energy, 89, 687–701. https://doi.org/10.1016/j.energy.2015.06.024.
[3] Chaudhari, C.D., Waghmare, S.A., and Kotwal, A. (2013). Numerical Analysis of Venturi Ducted Horizontal Axis Wind Turbine for Efficient Power Generation Numerical Analysis of Venturi Ducted Horizontal Axis Wind Turbine for Efficient Power Generation. International Journal of Mechanical Engineering and Computer Applications, 1(5), 90–93.
[4] Taghinezhad, J., Alimardani, R., Mosazadeh, H., and Masdari, M. (2019). Ducted Wind Turbines A Review. International Journal on Future Revolution in Computer Science and Communication Engineering, 5(4), 19–25. http://www.ijfrcsce.org.
[5] Morel, T. (1975). Comprehensive Design of Axisymmetric Wind Tunnel Contractions. Journal of Fluids Engineering, 75-FE-17, 225–233.
[6] Tabrizian, A. (2013). An Experimental Study of the Effects of Sweep Wing on the Boundary Layer of 2D Wing [Sharif University of Technology]. http://repository.sharif.edu/resource/389977/-/&from=search&&query=swept-wing&field=subjectkeyword&count=20&execute=true.
[7] Bardal, L.M. and Sætran, L.R. (2017). Influence of turbulence intensity on wind turbine power curves. Energy Procedia, 137, 553–558. https://doi.org/10.1016/j.egypro.2017.10.384.
[8] Unalmis, O.H. (2002). On the possible relationship between low frequency unsteadiness of shock-induced separated flow and Goertler vortices. Fluid Dynamics, June 1996. https://doi.org/10.2514/6.1996-2002.