Rüzgâr Türbinlerinde Kiriş Yapısının Performansa Etkisinin Sayısal Olarak İncelenmesi

Öz

Rüzgâr türbinlerinde kanat modelleri yüksek performans için büyük öneme haizdir. Bu çalışmada, rüzgâr türbini kanat profili yaygın olarak kullanılan NACA 2412 modelinde kiriş yapısının aerodinamik performansa etkisi sayısal olarak incelenmiştir. RHİNOCEROS programı ile modellenen kanat profilleri ANSYS FLUENT programı ile akış analizleri yapılmıştır. Sayısal analizler, 3,24x105 Reynolds sayısında (Re) ve k-ε realizable türbülans modeli kullanılarak gerçekleştirilmiştir. 0,25 m veter uzunluğuna bağlı olarak kanat profillerinin açıklık oranı 5’tir. Serbest hava akım hızının 20 m/s olduğu çalışmada kanat profilleri kaldırma (CL), sürüklenme (CD) katsayıları ve aerodinamik performansı (CL / CD) incelenmiştir. Düz kanat profili (K0), maksimum kaldırma katsayısına 22,5° hücum açısında ulaşırken, kiriş yapısı ile modifiye edilmiş kanat (K1) profili 25° hücum açısında ulaşmıştır. K1 kanadının maksimum CL değeri 1,1462 olup K0 kanadının maksimum değerinden %1 fazladır. İrtifa kaybı sonrası, K1 kanat profilinin ortalama CL / CD değeri K0 kanadının ortalama değerinden %5 fazla olarak gerçekleşmiştir. Kiriş yapısı yüksek hücum açılarında, aerodinamik performansa olumlu yönde etkisi bulunmaktadır.

Anahtar Kelimeler

• NACA-0012
• üçgen kiriş yapısı
• aerodinamik performans
• HAD

Numerical Investigation of Rib Structure Effects On Performance of Wind Turbines

Öz

In order to achieve high aerodynamic performance in wind, airfoil profile geometries have significant effect. In this study, NACA 2412 airfoil which is widely used for wind turbines was investigated numerically. Technical drawings were drawn by sing CAD program RHINOCEROS and flow analysis was performed by using ANSYS FLUENT. In our study, Reynolds number was 3,24x105 and k-ε realizable was chosen as turbulence model solver. Chord length is 0,25 m and spanwise is 5. Airfoil models were investigated in terms of lift (CL) and drag (CD) coefficient while free stream air velocity is 20 m/s. Smooth blade profile reached its maximum lift coefficient at 22,5° on the other hand modified profile reached its maximum value of lift coefficient at 25° angle of attack. K1 airfoil profile has reached its maximum value as 1,1462 and this value is %1 more than K0’s value. It was observed that K1 profile’s average CL / CD is %5 more than K0’s average value after stall. Triangular rib structure contributes positively on aerodynamic performance during high angle of attack.

Anahtar Kelimeler

• NACA-0012
• triangular rib structure
• aerodynamic performance
• CFD

Kaynakça

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