Performance Improvement for Wind Turbines

As a platform independent provider of aerodynamic retro-fit solutions, over 360.000 SMART BLADE vortex generators are already installed on more than 2000 turbines across 17 different platforms.

We are confident to offer the best turn key solution on the market. The key values of our product are:

Material Selection: We use superior thermoplastics and 3M adhesives with excellent durability and weather resistance. There are NO major VG failures so far.

Optimal Performance: Every new platform is profiled with a novel in-field flow visualization (SMARTViz), in order to determine the optimal VG position for each specific blade type.

Certified Performance Assessment: We offer full and transparent support with performance assessment. Our method has been successfully approved by DNV-GL several times.

Proven AEP increase: With a total number of 102 test turbines of different types across 28 different sites worldwide, an average gain in annual energy production (AEP) of 2.1% is proven.

Proper Installation: Once the VG pattern is developed, a precise installation process is formulated to assure accurate and repeatable VG placement during installation.

Speed: Utilizing custom templates, processes, self-adhesive and skilled rope access technicians an average of one working day of downtime per turbine is achieved.

The Technology

The blades of large, pitch regulated wind turbines often suffer from poor aerodynamic properties at the root region due to blade production and operation limitations. The required structural twist of the blades is very expensive to realize and therefore, there is always a potential for aerodynamic improvement of their performance.

Vortex Generators (VGs) improve the performance of the blades by energizing the flow around its surface and reducing flow separation. The performance of the entire turbine in terms of power, loads and service life are therefore being improved.

VGs delay flow seperation, increase the AEP of the turbine and reduce dynamic stall loads

The Benefits

Performance improvement of a VG turbine
FEA simulation of blade equipped with VGs
Sound pressure level of VGs
Flow separation with and without VGs

Impact on power curve: The VGs increase the turbine power in partial load. The nominal rated power of the turbine is not affected. The VG effect on the power curve is wind speed dependent. Therefore the overall AEP improvement is depending on a site's local wind speed distribution. Extensive field testing and a detailed performance evaluation is used to determine the turbine type specific VG effect.

No impact on loads: Following IEC 61400-1, load simulations and a numerical study on a generic wind turbine were conducted. It was investigated which effect the VGs have on the blades' structural integrity. No impact on the failure index of the turbine was found. Additional to that generic investigation, already three turbine manufactures have directly involved their load department to analyze a potential load increase due to VGs on their specific turbine. The clear statement is: The VGs have no influence on the design loads of the turbine.

Noise emissions: We conducted aeroacoustic wind tunnel tests, to clarify the effect of the Vortex Generators on the noise emissions. The results of the tests show that the sound pressure level at high angles of attack is considerably lower when VGs are used. Separated flow is always a source of noise. Delaying stall using VGs, subsequently reduces the noise emissions of the turbine. There has been no reported issue of increased noise emissions on turbines with SMART BLADE VGs so far.

 

Optimized VG line: Every wind turbine blade is different. The in-filed flow visualization process we developed is highly customized to the blade type. This allows for the recapturing of the maximum amount of power production otherwise lost to aerodynamic stall in the root region of the blade.

 

Performance Evaluation

In order to verify the specific performance increase of VGs to an asset, SMART BLADE® on request offers a full performance evaluation after the installation of VGs. We have years of experience in the analysis of performance data and developed a sophisticated evaluation process, validated by DNV GL using high frequency SCADA data.

Performance improvement of a VG turbine.