Wind energy is the fastest growing alternate source of energy in the world since its purely economic potential is complemented by its great positive environmental impact. The wind turbine, whether it may be a Horizontal-Axis Wind Turbine (HAWT) or a Vertical-Axis Wind Turbine (VAWT), offers a practical way to convert the wind energy into electrical or mechanical energy. Although this book focuses on the aerodynamic design and performance of VAWTs based on the Darrieus concept, it also discusses the comparison between HAWTs and VAWTs, future trends in design and the inherent socio-economic and environmental friendly aspects of wind energy as an alternate source of energy.

Wind turbine design with emphasis on Darrieus concept Ion Paraschivoiu

Meeting future world energy needs while addressing climatic changes has led to greater strain on conventional power sources. One of the viable sustainable energy sources is wind. But the installation large scale wind farms has a potential impact on the climatic conditions, hence a decentralized small scale wind turbines is a sustainable option. This paper presents review of on different types of small scale wind turbines i.e., horizontal axis and vertical axis wind turbines. The performance, blade design, control and manufacturing of horizontal axis wind turbines were reviewed. Vertical axis wind turbines were categorized based on experimental and numerical studies. Also, the positioning of wind turbines and aero-acoustic aspects were presented. Additionally, lessons learnt from various studies/countries on actual installation of small wind turbines were presented.

A review on small scale wind turbines

Wind energy is one of the most promising renewable energy resources for power generation, and rapid growth has been seen in its acceptance since 2000. The most acceptable classification for wind turbines is by its axis of orientation: Horizontal Axis Wind Turbines (HAWT) and Vertical Axis Wind Turbines (VAWT). HAWTs are used in many countries for medium-to-large scale power projects, and most commercial installations around the globe are solely based on these turbines. On the other hand, HAWTs are not recognized as a viable option to harness the energy of the wind in urban areas, where the wind is less intense, much more chaotic and turbulent. VAWTs are suggested as a better choice for cities and isolated semi-urban areas. Several attributes have been suggested for the large-scale deployment of VAWTs, e.g., good performance under the weak and unstable wind, no noise and safety concerns, and aesthetically sound for integration in urban areas. Significant research has been published on wind turbine technology and resources assessment methodologies, and this review paper is a modest attempt to highlight some of the major developments of VAWTs, with a focus on the integration with urban infrastructure. Several recommendations have been drawn based on the state-of-the-art information on the subject for future studies and acceptance of wind turbines in the urban areas. It was concluded that further research is critical in making VAWTs a viable, dependable, and affordable power generation technology for many low and decentralized power applications.

A critical review of vertical axis wind turbines for urban applications

A review on computational fluid dynamic simulation techniques for Darrieus vertical axis wind turbines

CFD study of Savonius wind turbine: 3D model validation and parametric analysis

Hot corrosion behavior of TC11 titanium alloy treated by laser shock processing

Laser shock processing effects on isothermal oxidation resistance of GH586 superalloy

The Savonius wind turbine bears unique features in both aspects of rotor structure and torque production. Continual improvement of the Savonius wind turbine motivates the authors of this review to gather, classify and discuss the quintessential parts of the relevant studies. Unambiguous priority is granted to the turbulent flow surrounding the Savonius wind rotor. Flow patterns near the Savonius wind rotor are represented with distributions of static pressure near conventional and spiral Savonius wind rotors. Assorted geometric shapes of Savonius wind rotors are demonstrated to illuminate a panorama of the development of the Savonius wind rotor, as well as to highlight the connection between rotor-based solid boundary and flow structures near Savonius wind rotor blades. Limitations of existing analytical methods used to predict the performance of the Savonius wind rotor are interpreted. Advantages of both numerical and experimental techniques in acquiring aerodynamics forces, shaft torque and internal stress distribution for the Savonius wind rotor blade are enumerated, and the difficulties incurred by curved blades and the rotation of the rotor are analyzed as well. Optimal values of tip-speed ratio corresponding to maximum power coefficient or maximum torque coefficient are different for various geometric shapes of Savonius wind rotors, which sheds new light upon the relationship between flow characteristics and performance parameters associated with the Savonius wind rotor.

Haixia Liu

Papers

Hot corrosion behavior of TC11 titanium alloy treated by laser shock processing

Laser shock processing effects on isothermal oxidation resistance of GH586 superalloy

Review of fluid dynamics aspects of Savonius-rotor-based vertical-axis wind rotors

Flow structures and cavitation in submerged waterjet at high jet pressure

Resistance of curved surfaces to the cavitation erosion produced through high-pressure submerged waterjet