The blade performance is simulated with and without the add-ons by means of two case studies. Next, the experimental lift and drag polar data are imported into the software QBlade in order to design a generic rotor blade. The preferred configurations are the smallest MGF on the NACA63(3)618 and the medium-sized MGF combined with VGs on the DU97W300. In the latter, leading-edge transition is forced with Zig Zag (ZZ) turbulator tape. Furthermore, the clean and the tripped baseline cases are considered. The impact of different MGF heights including 0.25 %, 0.5 % and 1.0 % and a VG height of 1.1 % of the chord length is tested and evaluated. Static angles of attack between −5 and 17∘ at a Reynolds number of 1.5 million. Lift and dragĪre determined using a force balance and a wake rake, respectively, for The Technische Universität Berlin based on two airfoils that areĬharacteristic of different sections of large rotor blades. Wind tunnel tests are conducted at the Hermann-Föttinger Institut of Passive flow control devices is accompanied by a certain drag penalty. Thin angle profiles that are attached at the trailing edge in order to The suction side aiming at stall delay and increased maximum lift. Performance of airfoils and wind turbine rotor blades. This wind tunnel study investigates the aerodynamic effects of mini Gurneyįlaps (MGFs) and their combination with vortex generators (VGs) on the Similarly, the proposed active control solution can reduce the wind turbine noise level by up to 6.56 dB by modifying the sound pressure spectra at frequencies between 1 Hz. The aeroacoustic noise estimation shows that the active device can reduce the noise emission by moderating pressure fluctuation, stabilizing the flow field and influencing the vortex shedding. It is found that appropriate application of the active control solution can eliminate the wind turbine’s negative torque, avoid excessive alternating load on the rotor and improve the energy extraction efficiency. Furthermore, the impact of optimal combination of these factors was analyzed based on three different control strategies. The results indicate that Cμ plays crucial role in determining the airfoil performance, while the role of Lb is almost negligible. The factors include suction position relative to leading-edge (Ls), blowing position relative to trailing-edge (Lb) and jet coefficient (Cμ). Following validation of the numerical approach using wind tunnel experimental data on a static airfoil, an orthogonal experimental design method was used to analyze and optimize the operating factors. The Improved Delayed Detached Eddy Simulation turbulence model and the Ffowcs Williams-Hawkings acoustic analogy method are adopted to simulate the instantaneous flow field and predict the far field noise. The aeroacoustic noise emissions accomplished with this enhancement are evaluated. This paper aims to improve the aerodynamic performance of an H-type Darrieus wind turbine using an innovative fluidic flow control technique based on the synergistic effect of blowing and suction. This leads to a strong fluctuation in torque and a reduction in energy acquisition. The power efficiency of Darrieus wind turbines significantly deteriorates during rotation caused by periodic dynamic stall at low tip speed ratios. A look at the flow field pattern for the optimal design in comparison with the clean blade shows that the modified blade is able to generate more lift in the pre-stall region, while for the post-stall region, early separation and increased wake dominate the flow. Additionally, all configurations show similar trends for the instantaneous torque, where an increase is observed in pre-rated speed, whereas a decrease is noticed in the post-rated speed region. The rated speed is also shifted from 10 m/s to 8 m/s for most configurations. Results show that the presence of serration is capable of improving the annual power generation in all the investigated cities by up to 12%. The viability of the solution on an application is assessed using the Weibull distribution of wind in three selected regions. The optimal combination is found using the Taguchi method with three factors: Amplitude, wavelength, and serration thickness. The present work employs a statistical-numerical method to predict and optimize the shape of the serrations for maximum aerodynamic improvement. The result is supported by subsequent validation with three-dimensional numerical tools. Fluid flow interaction with the proposed serrations is explored for different wind conditions. Inspired by the remarkable flight characteristics of owls, an optimal trailing edge serration design is investigated and proposed for a wind turbine rotor blade. Abstract: For the rotor, achieving relatively high aerodynamic performance in specific wind conditions is a long-term goal. Aerodynamic Optimization of Trailing-Edge-Serrations for a Wind Turbine Blade Using Taguchi Modified Additive Model.
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