Effect of Wind Tunnel Blockage on the Performance of a Horizontal Axis Wind Turbine with Different Blade Number

Energies

Massimiliano Burlando¹  Francesco Castellani²  Matteo Becchetti²  A.S. Huzayyin³  Abdelgalil Eltayesh³  HeshamM. El-Batsh³  MagdyBassily Hanna⁴ 

[1] Department of Civil, Chemical, and Environmental Engineering, University of Genoa, Via Montallegro 1, 16145 Genoa, Italy;Department of Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy;Mechanical Engineering Department, Benha Faculty of Engineering, Benha University, Benha 13512, Egypt;Mechanical Power and Energy Department, Faculty of Engineering, Minia University, Minia 61519, Egypt;

关键词: wind tunnel blockage;    small-size wind turbines;    wind tunnel tests;    CFD simulations;   

DOI  :  10.3390/en12101988

来源: DOAJ

【 摘 要 】

Blockage corrections for the experimental results obtained for a small-scale wind turbine in a wind tunnel are required in order to estimate how the same turbine would perform in real conditions. The tunnel blockage is defined as the ratio of the wind turbine swept area to the wind tunnel cross-section area. Experimental measurements of the power coefficient were performed on a horizontal-axis wind turbine with two rotors of diameter equal to 2 m and different numbers of blades, namely three and five. Measurements were carried out for different tip speed ratios in the closed circuit open test section wind tunnel of the University of Perugia (Italy). The obtained experimental results were compared with the numerical ones carried out in free conditions by using a CFD approach based on the steady-RANS method with the SST k-$\omega$ turbulence model, adopting the multiple reference frame (MRF) strategy to reduce the computational effort. The comparison showed that the maximum value of blockage, which is reached in the asymptotic limit at very large tip speed ratio (TSR) values, does not depend appreciably on the number of blades. A higher number of blades, however, makes the occurrence of the maximum blockage come earlier at lower TSRs.

【 授权许可】

Unknown