Abstract

Siting wind turbines in urban areas is a good idea for on-site energy generation. However, the efficiency of the wind turbine in the urban areas is the main concern due to the uncertainty and the turbulent wind in the urban area. As one of the solutions for this problem vertical axis wind turbines are considered suitable to be installed in the urban environment due to their ability to withstand the turbulent wind condition of the urban area. However VAWTs are faced with a challenge of poor self-starting capability. These challenges can be overcome through an improved design of VAWTs. This paper presents the design and performance investigation of a straight-bladed vertical axis wind turbine with augment radial arm (AR-VAWT). The AR-VAWT consists of three main vertical blades and six airfoil radial arms. The performance of the AR-VAWT was evaluated and compared with a conventional VAWT under similar experimental conditions. The experiment was conducted for different averaged wind speed conditions; 4.57 m/s, 4.38 m/s, 4.00 m/s and 3.89 m/s respectively. The results showed that at 4.57 m/s the maximum coefficient of power (Cpmax) and the rotational speed (RPM) of the AR-VAWT is 113%and 20% higher than the Cpmax and the RPM of the conventional VAWT under similar experimental conditions. Further results shows that an improvement in the performance of the AR-VAWT is also observed in all the conditions of wind speed where the AR-VAWT outperformed the conventional VAWTs.

Key words: Wind energy, wind turbine, VAWT, Radial arms, urban area