S809 Kanat Profili Etrafındaki Sınır Tabaka Akışının Emme Tekniği ile Aktif Kontrolünün Sayısal İncelenmesi

Abstract

Bu çalışmada, sınır tabaka akışı aktif kontrol yöntemlerinden biri olan, sınır tabakadan kanat içerisine hava emilmesi prensibine dayanan emme tekniği kullanılarak bir rüzgar türbini kanadının aerodinamik performansının arttırılması hedeflenmiştir. Emme işlemi daimi bir jet vasıtasıyla gerçekleştirilmiş, kanat modeli olarak rüzgar türbini uygulamalarında yaygın olarak kullanılan S809 kanat profili tercih edilmiştir. Çalışma parametreleri olarak, üç ayrı jet konumu (Ljet = 0.1c, 0.26c, 0.36c) ve üç ayrı jet oranı (Rjet = 0.1, 0.3, 0.5) seçilmiştir. Emme jeti genişliği sabit olup veter uzunluğunun %2.5’i kadar ve emme jeti açısı (θjet) bölgesel jet yüzeyine 90° olacak şekilde ayarlanmıştır. İki boyutlu türbülanslı akış için sayısal analiz; α = 15° hücum açısında ve Re = 106’da SST k-ω türbülans modeli kullanılarak gerçekleştirilmiştir. İlk olarak emme jeti konumunun etkisi, ardından en iyi sonucu veren emme jeti konumu seçilerek emme jeti oranının etkisi araştırılmıştır. Kanat profili etrafındaki akışa ait simülasyon sonuçları incelendiğinde, en iyi sonuç emme jeti konumu 0.36c (Jet-3) ve emme jeti oranı 0.5 olduğunda alınmıştır. Jet kullanılmadığı duruma göre CL/CD oranı 17.92’den 273.03’e yükselmiştir. Emme jeti ile kontrol yönteminin uygulanması ile kontrolsüz duruma göre Cl değeri yaklaşık olarak 1.211’den 1.8’e yükselmiş, Cd değeri ise 0.068’den 0.0066’ya düşmüştür.

Keywords

• Aktif kontrol yöntemi,Emme jeti,S809 kanat profili,Sınır tabaka akışı

Numerical Investigation of Active Control of Boundary Layer Flow Around S809 Airfoil with Suction Method

Abstract

In this study, it is aimed to increase the aerodynamic performance of a wind turbine blade by using the suction technique which is one of the active control methods of boundary layer flows based on the principle of air intake from the boundary layer into the blade. Suction is defined as a continuous jet and the S809 airfoil is preferred which is widely used in wind turbine applications as a blade model. Three different jet positions (Ljet = 0.1c, 0.26c, 0.36c) and three different jet ratios (Rjet = 0.1, 0.3, 0.5) are selected as study parameters. The suction jet width is fixed and is 2.5% of chord length and the suction jet angle (θjet) is 90° to the local jet surface. Numerical analysis for a two-dimensional turbulent flow is performed using SST k-ω turbulence model with an angle of attack of α =15° and Re=106. Firstly, the effect of the suction jet position is investigated and then the effect of the suction jet ratio is examined with an optimum suction jet position that showed the best result. When the simulation results of the flow around the airfoil are examined, the best result is obtained when the suction jet position is jet-3 (0.36c) and the suction jet ratio is 0.5. CL/CD ratio is increased from 17.92 to 273.03 compared to the no-jet situation. By the application of the suction jet control method, the CL is increased approximately from 1.211 to 1.8 and the CD is decreased from 0.068 to 0.0066 in comparison to the uncontrolled case.

Keywords

• Active control method,Suction jet,S809 airfoil,Boundary layer flow

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