Experimental Investigation of the Effect of Hydrophobic Coating on Aerodynamic Parameters of Airfoils

Year 2023, Volume: 15 Issue: 1, 186 - 194, 31.01.2023

Fevzi Şahin , İsmayil İsmailov , Hakan Özcan

https://doi.org/10.29137/umagd.1191778

Abstract

In this study, an experimental study was carried out on NACA 4418 wing profile. The airfoil was covered with two different materials by spray coating method, the degrees of wetting (water droplet contact angle with the surface, θ) were determined. The three different surfaces that are as normal (θ = 59o <90o: hydrophilic), hydrophobic (θ = 93o> 90o) and superhydrophobic (θ = 154o> 150o) were obtained. For these three different situations, the lift and drag coefficients were determined experimentally in the wind tunnel at a free flow velocity of 15 m / s (Re = 253.196) and 6 different angle of attack (-10 °, -5 °, 0 °, 5 °, 10 °, 15 °) and compared with each other. The results showed that when the hydrophobic and superhydrophobic properties to the normal (hydrophilic) airfoil were introduced, the lift coefficients of airfoil increased by an average of 15% and 23%, respectively for all the studied attack angles. In addition, adding hydrophobic and super hydrophobic properties to the normal (hydrophilic) airfoil decreased the drag coefficients of the airfoil by 12% and 20%, respectively for all the studied attack angles.

Keywords

Spray coating, hydrophobic, Superhydrophobic, Lift coefficient, Drift coefficient

Hidrofobik Kaplamanın Kanat Profillerinin Aerodinamik Parametrelerine Etkisinin Deneysel İncelenmesi

Abstract

Bu çalışmada NACA 4418 kanat profile üzerinde deneysel bir çalışma yürütülmüştür. Kanat profili spray kaplama yöntemi ile iki farklı malzeme ile kaplanmış, ıslanırlık derecesi (su damlasının yüzey ile temas açısı, θ) belirlenmiştir. Normal (θ=59o<90o: hidrofilik), hidrofobik (θ=93o>90o) ve süperhidrofobik (θ=154o>150o) olmak üzere üç farklı kanat profile yüzeyi elde edilmiştir. Bu üç farklı durum için, kaldırma ve sürüklenme katsayıları, 15 m/s (Re=253.196) serbest akım hızında ve 6 farklı hücum açısında (-10°, -5°, 0°, 5°, 10°, 15°) rüzgar tünelinde deneysel olarak belirlenerek birbiriyle karşılaştırılmıştır. Sonuçlar, normal (hidrofilik) kanat profiline, hidrofobik ve süperhidrofobik özellik kazandırılmasının kanat profilinin kaldırma katsayılarını tüm hücum açıları dikkate alındığında sırasıyla ortalama %15 ve %23 oranında iyileştirdiğini göstermiştir. Ayrıca normal (hidrofilik) kanat profiline, hidrofobik ve süperhidrofobik özellik kazandırılması kanat profilinin sürüklenme katsayılarını tüm hücum açıları dikkate alındığında sırasıyla ortalama %12 ve %20 oranında düşürmüştür.

Keywords

Kanat profili, Sprey kaplama, Hidrofobik, Süperhidrofobik, Kaldırma katsayısı, Sürüklenme katsayısı

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