Wind tunnel and numerical study of a small vertical axis wind turbine

Howell, Robert J.; Qin, Ning; Edwards, Jonathan; Durrani, Naveed

doi:10.1016/j.renene.2009.07.025

Cited by 634 publications

(336 citation statements)

References 3 publications

Supporting

Mentioning

312

Contrasting

Unclassified

Order By: Relevance

“…In terms of the manufacturing process and fabrication costs, the Darrieus rotor-straight blade or giromill showed a reliable configuration. The two blades of the giromill are generally named the H-rotor (Mertens et al, 2003, Howell et al, 2010. Hence, a deep consideration and review will be conducted on the Darrieus rotor-straight blade.…”

Section: Vertical Axis Wind Turbine (Vawt)mentioning

confidence: 99%

Synergy of Savonius and Darrieus types for vertical axis wind turbine

Almotairi¹,

Mustapha

Ariffin

et al. 2016

Int. j. adv. appl. sci

View full text Add to dashboard Cite

Wind energy is one of the renewable energy sources or technology which is the cheapest the and cleanest compared to other types of energy. A new market in wind technology has emerged that has the means of efficiently convert the wind energy to a usable form of energy which is electricity. The foundation of this new technology is the wind turbine. Wind turbine is a machine that transfers fluid energy that passed through the blades and shaft to mechanical energy and transforms the mechanical energy to electricity through the use of a generator. Vertical Axis Wind Turbine (VAWT) has been popular due to its small, quiet and simple design. Darrieus, Savonius, and Vane are the example of VAWT. This vertical axis wind turbine represents a suitable alternative for wind power extraction in many developing countries. The reason for this is mainly because of the advantage over the horizontal axis type such as Simple construction, extremely cost effective and acceptance of wind flow from any direction without orientation. In spite of these advantages, vertical axis wind turbine is not gaining popularity because of low efficiency of the Savonius type rotor and low starting torque of the Darrieus type wind machines. Hence, the objective of this paper is to design a VAWT by combining the Savonius type and Darrieus type so that the combination of these both designs is met the expectation to have a good performance of wind turbine.

show abstract

Section: Vertical Axis Wind Turbine (Vawt)mentioning

confidence: 99%

Synergy of Savonius and Darrieus types for vertical axis wind turbine

Almotairi¹,

Mustapha

Ariffin

et al. 2016

Int. j. adv. appl. sci

View full text Add to dashboard Cite

show abstract

“…The external dimensions are 14D x 30D x 12D and the wall distance is 1*10-4c, necessary for an averaged y+ < 5, following a mesh sensitivity analysis performed in order to verify if the grids adopted were sufficiently fine to resolve the primary flow features. Figure 1 shows the analysis for the 2D model for the 17m Darrieus VAWT and the 3D model for the small H-Darrieus VAWT; the 3D model of the SANDIA turbine has been excluded from this analysis due to the high number of cells of the domain, but the mesh adopted is similar to that used by Howell [16] and Zhang [17].…”

Section: Numerical Approachmentioning

confidence: 99%

“…One advantage of the 3D approach could be a better estimation of dynamic stall and also lag effects due to the unsteady flow. The 2D CFD models cannot fully describe the complex dynamics of the flow whilst the 3D CFD model can take into account the near and far field flow developments surrounding the real geometry of the wind turbine, as also shown by Howell [16]. Figure 3 compares the predicted and measured coefficient of power (c p ) and power production curves for the SANDIA 17m Darrieus turbine.…”

Section: Verification Of the Cfd Modelmentioning

confidence: 99%

3D URANS analysis of a vertical axis wind turbine in skewed flows

Orlandi

Collu

Zanforlin

et al. 2015

Journal of Wind Engineering and Industrial Aerodynamics

View full text Add to dashboard Cite

The article demonstrates the potential of an unsteady RANS 3D approach to predict the effects of skewed winds on the performance of an H-type vertical-axis wind turbine (VAWT). The approach is validated through a comparison between numerical and experimental results for a full-scale Darrieus turbine, demonstrating an improved prediction ability of 3D CFD with respect to both 2D CFD and semi-empirical models based on the double multiple stream tubes method. A 3D URANS approach is then adopted to investigate the power increase observed for a straight-bladed small-scale turbine in a wind tunnel when the rotational axis is inclined from 0 • to 15 • from the vertical. The main advantage of this approach is a more realistic description of complex three-dimensional flow characteristics, such as dynamic stall, and the opportunity to derive local blade flow conditions on any blade portion during upwind and downwind paths. Consequently, in addition to deriving the turbine overall performance in terms of power coefficient, a better insight into the temporal and spatial evolution of the physical mechanisms is obtained. Our principal finding is that the power gain in skewed flows is obtained during the downwind phase of the revolution as the end part of the blade is less disturbed by the wake generated during the upwind phase.

show abstract

“…The straight turbine rotor blade, with an aspect ratio of 4:1, operates at relatively low tip speeds and its performance shows a clear dependence on the rotor blade surface finish. Performance is enhanced by having the surface of the turbine roughened at a critical Reynolds number 30,000 [13]. Fang Feng combined Savonius rotor with H-rotor and reported that, H-rotor is self-started at low tip speed ratio [14].…”

Section: Introductionmentioning

confidence: 99%