The Effect of Riblets on the Aerodynamic Performance of NACA 0018 Airfoil

Year 2024, Volume: 39 Issue: 1, 119 - 132, 28.03.2024

Emre Güler , Engin Pınar , Tahir Durhasan

https://doi.org/10.21605/cukurovaumfd.1459405

Abstract

In this numerical study, riblets on the airfoil were utilized to enhance the aerodynamic performance of NACA0018 airfoil. Riblets of identical height and base length are strategically placed on the suction surface of the airfoil with varying spacing ratios along the flow direction (x) and chord length (c), specifically x/c = 0.3 and 0.7. Four distinct riblet airfoil models are subjected to computational fluid dynamics (CFD) analysis within an angle of attack range from 0° to 21° at a Reynolds number of Re=1×105. The obtained results are systematically compared with the performance of the plain airfoil. Numerical analyses reveal the significant influence of the spacing ratio on flow control and the overall aerodynamic performance of the airfoil, establishing a direct relationship with riblet spacing. The presence of riblet structures is observed to increase the lift coefficient, concurrently delaying the stall angle up to 19°. Notably, the ribbed structures effectively mitigate the interaction between the laminar separation bubble and trailing edge separation, leading to a reduction in turbulent kinetic energy values.

Keywords

Riblet, Computational fluid dynamics, Flow control, Aerodynamic performance of airfoil

Yivlerin NACA 0018 Kanat Profilinin Aerodinamik Performansı Üzerine Etkisi

Abstract

Bu sayısal çalışmada NACA 0018 kanat profilinin aerodinamik performansını arttırmak için yivli yapılar kullanılmıştır. Aynı yüksekliğe ve taban uzunluğuna sahip olan yivler, akış yönü doğrultusunun (x) veter uzunluğuna (c) oranı, x/c = 0,3 ve 0,7 arası boyunca kanat emme yüzeyine farklı boşluk oranları ile yerleştirilmişlerdir. Dört farklı yivli kanat modeli hücum açısının 0o ile 21o arasında ve Reynolds sayısının Re=1×105 değerinde hesaplamalı akışkanlar dinamiği (HAD) ile analiz edilmiştir. Yivli yapıların etkisini göstermek için elde edilen sonuçlar yalın kanat modeli ile kıyaslamalı olarak sunulmuştur. Sayısal çözümlemelerden elde edilen veriler yiv boşluk oranının akış kontrolü üzerinde etkili olduğunu ve kanat aerodinamik performansının yiv boşluk oranı ilişkili olduğunu ortaya koymuştur. Yivli kanat modelinin taşıma katsayısını artırdığını ve tutunma kaybı açısını 19o’e kadar ötelediği gözlemlenmiştir. Ayrıca yivli yapıların laminer ayrılma kabarcığının ve firar kenarı yarılması etkileşimini bastırdığını böylelikle türbülans kinetik enerji değerlerini azalttığı gözlemlenmiştir.

Keywords

Yivli yüzey, Hesaplamalı akışkanlar dinamiği, Akış kontrolü, Kanat aerodinamik performans

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