Numerical Evaluation of the Flow around a New Vertical Axis Wind Turbine Concept

Abstract

In order to develop a sustainable economy based on the efficient use of green energy resources, it is necessary to research and innovate systems such as wind turbines. In this paper, a new configuration for vertical axis wind turbines was proposed and numerically analyzed using CFD methods. The concept is based on solving the starting problem of lift-based vertical axis wind turbines. The new concept consists of three blades with different chords, arranged at different radii so that the interaction between the blades is reduced and the operation in the vortex wake is minimal, thus reducing the losses. Through comparing a classic case of an H-Darrieus wind turbine with the new concept, not only were satisfying results regarding the blade-to-blade interaction presented, but an increased efficiency of up to 10% was also observed. Among the presented results is the variation of the vorticity magnitude at different positions of the blades, thus, the concept’s blade-to-blade interaction is reduced. Conclusions drawn after the investigation are in favor of the proposed geometry and the concept should be pursued further.

Simulation Study of the Effect of Atmospheric Stratification on Aircraft Wake Vortex Encounter

“…Pan et al [18] identified the hazard zone of a wake vortex encounter during approach landing using RMC and overload increments. The wake vortex evolution is closely related to the atmospheric environment, and the environmental changes in the near-surface layer are complex and diverse, with wind speed, atmospheric turbulence, and buoyancy effects affecting the wake vortex evolution [19,20]. Research needs to be conducted in order to solve the problem that the existing wake prediction models cannot consider the influence of all meteorological conditions on the wake vortex evolution [21,22].…”

High-precision numerical investigation of a VAWT starting process

“…In this case, a combined solution of installing plants and of developing more energy efficient harnessing [27] and distribution systems should lower the growth rate of power requirements [2]. Many studies have been done regarding improving the efficiency of wind turbines in which the performance of various blade shapes is analysed [29][30][31], the impact on the power coefficient of the disposition of the blades [32] and the number of rotors studied [33] and even the power output of multiple cluster dispositions of identical turbines numerically simulated [34,35]. The authors in [36] have reviewed the current studies in performance improvement with geometry variations regarding the Savonius VAWTs.…”