In recent era, research and development activities in the field of renewable energy, especially wind and solar, have been considerably increased, due to the worldwide energy crisis and high global emission However, the available technical designs are not yet adequate to develop a reliable distributed wind energy converter for low wind speed conditions The Savonius rotor appears to be particularly promising for such conditions, but suffers from a low efficiency Till now, a number of experimentations have been carried out in the area of Savonius rotor to increase its efficiency These large-scale experimentations involve massive costs and hazards In this context, computational studies have shown a significant importance to carry out the research with large number of physical designs and parameters Over the past four decades, investigations have been carried out with various computational methodologies and turbulence models to optimize the different parameters and hence the efficiency of these rotors In the present paper, a detailed review of various computational methods addressing the influence of various operating parameters and augmentation techniques has been reported From this review study, it is observed that with the selection of a proper computational methodology, the design, performance, and efficiency of a Savonius rotor can be enhanced significantly

Review on the numerical investigations into the design and development of Savonius wind rotors

Small scale wind turbines installed within the built environment is classified as micro generation technology This paper reports the investigation results of wind power application in buildings First, general information is given for common type of wind turbines are used on buildings Second, the wind aerodynamics and wind flows over the buildings are investigated based on local meteorological data and local building characteristics However, to receive the highest potential wind energy resource and avoid turbulent areas, the tool of Computational Fluid Dynamics (CFD) has to be used to model the annual wind flows over buildings to help analyze, locate, and design wind turbines on and around buildings Three different sample models for buildings and rural residential areas are explained with CFD models

A technical review of building-mounted wind power systems and a sample simulation model

Numerical study of detailed flow field and performance of Savonius wind turbines

Experimental investigation of helical Savonius rotor with a twist of 180

Performance improvement of Savonius rotor using multiple quarter blades – A CFD investigation

The unsteady pressure field and the aerodynamic performances of a Savonius rotor based on the discrete vortex method

Vortical structures in the wake of the savonius wind turbine by the discrete vortex method

Presently, there exist few numerical methods which treat the inverse problem for the determination of the geometry of wind turbine blades. In this work, authors intend to solve the inverse optimum project for horizontal axis wind turbine in which the selection of the circulation distribution is obtained by resolving two variational problems: the first consists in sorting the circulation distribution on the lifting line, which, for a given power extracted by the wind turbine, minimizes the loses due to the induced velocity. In the second, the optimal circulation distribution is selected such that the kinetic energy of the wind downstream of the rotor disc is minimum, when the energy extracted by the wind turbine for one rotating period is imposed. A code has been developed which incorporates the real pitch of the helicoidal vortex wake. Very promising results have been obtained: the circulation distribution for a given extracted power and the chord lengths distribution law along the blade span.

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The Circulation Distribution on the Lifting Line for a Given Extracted Power

Despite the potentially harmful effects on health and environmental impacts correlated with non-exhaust emissions (e.g., brake, tire and road wear and resuspension), but very limited environmental research studies have measured the contribution of vehicle non-exhaust emissions in real-world measurements and at different road segment types. Therefore, to fill this gap in academic literature, the main purpose of this study is to collect the knowledge base required to orient towards more sustainable mobility. During July 2019, continuous real-world measurements of non-exhaust particles (NEPs) were recorded over three different road segment types (urban, rural and motorway) in the city of Bron, near Lyon (France). Data were obtained using a native algorithm based on the GRIMM analyzer, series 1.108 Portable Aerosol Spectrometer. Results have confirmed abundant fine/coarse non-exhaust particle emissions which increase with the average vehicle speed and during sharp acceleration/deceleration manoeuvers. Motorway area has recorded the highest particle number concentrations as compared to urban and rural areas, which reaches 1.85 × 107 cm−3 due to increased vehicle speed, pavement materials and abrupt vehicle acceleration and deceleration maneuvers. In addition, the highest PM ratio was registered on motorway area and the lowest PM ratio appeared on urban road due to vehicle speed. It has been concluded that NEPs depended on the changes in driving conditions and road pavement type. 

Ali Helali

Papers

The unsteady pressure field and the aerodynamic performances of a Savonius rotor based on the discrete vortex method

Vortical structures in the wake of the savonius wind turbine by the discrete vortex method

The Circulation Distribution on the Lifting Line for a Given Extracted Power

Investigations on vehicle non-exhaust particle emissions: real-time measurements

Statistical Model for Estimating Exhaust CO2 Emissions from Heavy-Duty Trucks