Farklı Profillerden Meydana Gelen Kanat Modelinde Yüzey Akış Davranışlarının İncelenmesi

Öz

Bu makalede, yüzey yağ görselleştirme yöntemi kullanılarak dört farklı profilden oluşan bir kanat modeli üzerinde akış davranışları incelenmiştir. Kanadın ve kanadı oluşturan profillerin yüzeyindeki akış davranışları üç farklı Reynolds sayısında (2x105, 3x105 ve 4x105) ve 0 ile 40 derece arasında değişen farklı hücum açılarında sunulmaktadır. Deneyler düşük hızlı bir rüzgâr tünelinde gerçekleştirilmiştir. Yüzey görüntüleme deneylerinden elde edilen ve akış davranışını yansıtan ayrılma noktası, yeniden bağlanma noktası ve kabarcık uzunluğu değerleri sunulmuştur. 0-16 derece arasındaki hücum açılarında yüzeydeki akış laminerden türbülansa dönüşmeye çalışırken, türbülanslı akış ise 24-40 derece arasındaki hücum açılarında tüm yüzeye yayılmaya ya da yeniden tutunmaya çalışmaktadır. Hücum açısının veya Reynolds sayısının artması x/c değerlerinde sayısal olarak azalmaya neden olmuş, yüzey ayrılma balonunu zayıflatmış ve hücum kenarına doğru kaymasına neden olmuştur. X/c değeri açısından kanat modeli genel olarak 0 ve 8 derecede B profiline, 16 derecede ise A profiline yakın bir trend izlemektedir. Ayrıca kanat modelindeki akış davranışları, akış fenomenleri açısından A ve B profillerine benzediği görülmüştür.

Anahtar Kelimeler

• Kanat modeli
• Farklı profiller
• Akış davranışları
• Yağ görselleştirmesi

Investigation of Surface Flow Behaviors on Wing Model Made of Different Airfoils

Öz

This article is focused on the flow behavior observed using the surface oil visualization method on a wing model consisting of four airfoils. In this way, it is aimed to contribute to the insufficient number of literature studies in which flow behaviors are examined by visualization in the wing model consisting of different profiles. The flow behaviors on the surface of the wing and the surface of airfoils forming the wing are presented at three different Reynolds numbers (2x105, 3x105 and 4x105) and a range of distinct attack angles ranging from 0 to 40 degrees. The tests were applied in a low-speed wind tunnel. After the surface imaging experiments, separation point, reattachment point, and bubble length values reflecting flow behavior were measured for the wing and each airfoils. The flow on surface was trying to transition from laminar to turbulent at angles of attack between 0-16 degrees and the turbulent flow attempted to spread or reattach over the entire surface at between 24-40 degrees. Increasing of the angle of attack and Reynolds number led to reducing the x/c values numerically, weakening the surface separation bubble, and inducing it to shift towards the leading edge. In terms of x/c value, the wing model generally follows a trend close to airfoil B at 0 and 8 degrees and close to airfoil A at 16 degrees. Additionally, the flow behaviors on the wing model are similar to airfoils A and B in terms of the flow phenomena.

Anahtar Kelimeler

• Different airfoils
• Flow behaviors
• Oil visualization
• Wing model

Kaynakça

1. 1. White, F.M., 1991. Viscous fluid flow. Second Edition, McGraw-Hill Inc., New York, 376.
2. 2. LaGraff, J.E., Ashpis, D.E., 1998. Minnowbrook II 1997 workshop on boundary layer transition in turbomachines. National Aeronautics and Space Administration, NASA/CP-1998-206958, 345.
3. 3. Versteeg, H.K., Malalasekera, W., 1995. An introduction to computational fluid dynamics the finite volume method. Longman Scientific and Technical, 47.
4. 4. Cherubini, S., Picella, F., Robinet, J.C., 2021. Variational nonlinear optimization in fluid dynamics: the case of a channel flow with superhydrophobic walls. Mathematics, 9(53), 1-25.
5. 5. Schlichting, H., Gersten, K., 2017. Boundary-layer theory. Ninth Edition, Springer-Verlag Berlin Heidelberg, 419-420.
6. 6. Bowles, R.I., 2000. Transition to turbulent flow in aerodynamics. Philosophical Transactions: Mathematical, Physical and Engineering Sciences, 358(1765), 245-260.
7. 7. Horton, H.P., 1968. Laminar separation bubbles in two and three-dimensional incompressible flow. PhD Thesis, University of London, 28-30.
8. 8. Sandham, N.D., 2008. Transitional separation bubbles and unsteady aspects of airfoil stall. The Aeronautical Journal, 112(1133), 395-404.

9. 9. Genç, M.S., Karasu, İ., Açıkel, H.H., 2012. An experimental study on aerodynamics of NACA2415 airfoil at low Re numbers. Experimental Thermal and Fluid Science, 39, 252-264.
10. 10. Karthikeyan, N., Sudhakar, S., Suriyanarayanan, P., 2014. Experimental studies on the effect of leading-edge tubercles on laminar separation bubble. AIAA 2014-1279. 52nd Aerospace Sciences Meeting, 1-9.
11. 11. McGranahan, B.D., Selig, M.S., 2003. Surface oil flow measurements on several airfoils at low Reynolds numbers. 21st AIAA Applied Aerodynamics Conference, AIAA 2003-4067, 1-18.
12. 12. Liu, Y.C., Hsiao, F.B., 2014. Experimental investigation on critical Reynolds numbers aerodynamic properties of low aspect ratios wings. Procedia Engineering, 79, 76-85.
13. 13. Chen, J.H., Li, S.S., Nguyen, V.T., 2012. The effect of leading-edge protuberances on the performance of small aspect ratio foils. 15th International Symposium on Flow Visualization.
14. 14. Wang, L., Alam, M.M., Rehman, S., Zhou, Y., 2022. Effects of blowing and suction jets on the aerodynamic performance of wind turbine airfoil. Renewable Energy, 196, 52-64.
15. 15. Trie, D.Z., Hariyadi, S., Rifdian, I.S., 2023. Experimental study of fluid flow characteristics in wing airfoil NACA 43018 with parabolic vortex generator using oil flow visualization. Proceedings of the International Conference on Advance Transportation, Engineering, and Applied-Science (ICATEAS 2022), 52-69.
16. 16. Kumar, V., Mandal, A.C., Podda, K., 2024. An experimental investigation on the aerodynamic characteristics and vortex dynamics of a flying wing. The Aeronautical Journal, First view, 1-25.
17. 17. Mizoguchi, M., Kajikawa, Y., Itoh, H., 2016. Aerodynamic characteristics of low-aspect-ratio wings with various aspect ratios in low Reynolds number flows. Transactions of The Japan Society for Aeronautical and Space Sciences, 59, 2, 56-63.
18. 18. Ananda, G.K., Sukumar, Selig, M.S., 2015. Measured aerodynamic characteristics of wings at low Reynolds numbers, Aerospace Science and Technology, 42, 392-406.
19. 19. Li, Q., Kamada, Y., Maeda, T., Murata, J., Nishida, Y., 2016. Visualization of the flow field and aerodynamic force on a horizontal axis wind turbine in turbulent inflows. Energy, 111, 57-67.
20. 20. Seyhan, M., Akbıyık, H., Sarıoğlu, M., Keçecioğlu, S.C., 2022. The effect of leading-edge tubercle on a tapered swept-back sd7032 airfoil at a low Reynolds number. Ocean Engineering, 266(2), 112794, 1-13.
21. 21. Ghorbanishohrat, F., Johnson, D.A., 2018. Evaluating airfoil behavior such as laminar separation bubbles with visualization and IR thermography methods. Journal of Physics: Conference Series 1037, 052037, 1-10.
22. 22. Wei, Z.J., Qiao, W.Y., Liu, J., Duan, W., 2016. Reduction of endwall secondary flow losses with leading-edge fillet in a highly loaded low-pressure turbine. Proceedings of the Institution of Mechanical Engineers Part a Journal of Power and Energy, 230(2), 184-195.
23. 23. Genç, M.S., Özhan, G., Özden, M., Kiriş, M.S., Yıldız, R., 2018. Interaction of tip vortex and laminar separation bubble over wings with different aspect ratios under low Reynolds numbers. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 232(22), 4019-4037.
24. 24. Aşkan, A., Tangöz, S., Konar, M., 2023. An investigation of aerodynamic behaviors and aerodynamic performance of a model wing formed from different profiles. The Aeronautical Journal, 127(1310), 676-697.
25. 25. Aşkan, A., Tangöz, S., 2018. The impact of aspect ratio on aerodynamic performance and flow separation behavior of a model wing composed from different profiles. Journal of Energy Systems, 4(2), 224-237.
26. 26. Duan, W., Qiao, W., Wei, Z., Liu, J., Cheng, H., 2018. The influence of different endwall contouring locations on the secondary flow losses in a highly loaded low-pressure turbine. Proceedings of the ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, Volume 2B: Turbomachinery, V02BT41A018 ASME, 1-11.
27. 27. Sudhakar, S., Karthikeyan, N., Suriyanarayanan, P., 2019. Experimental studies on the effect of leading-edge tubercles on laminar separation bubble. AIAA Journal, 57(12), 5197-5207.
28. 28. Torres, G.E., Mueller, T.J., 2004. Aerodynamic impact of aspect ratio at low Reynolds number. AIAA Journal, 42(5), 865-873.
29. 29. Marchman, J.F., 1987. Aerodynamic testing at low Reynolds numbers. Journal Aircraft, 24(2),107-114.
30. 30. Elgammi, M., Sant, T., Ateeah, A.A., 2022. The influence of the flow separation bubble and transition location on the profile drag of three 4-digit NACA airfoil profiles. Wind Engineering, 46(3), 796-817.
31. 31. Traub, L.W., Cooper, E., 2008. Experimental investigation of pressure measurement and airfoil characteristics at low Reynolds numbers. Journal of Aircraft, 45(4), 1322-1333.
32. 32. Karasu, İ., Açıkel, H.H., Koca, K., Genç, M.S., 2020. Effects of thickness and camber ratio on flow characteristics over airfoils. Journal of Thermal Engineering, 6(3), 242-252.
33. 33. Dongli, M., Yanping, Z., Yuhang, Q., Guanxiong, L., 2015. Effects of relative thickness on aerodynamic characteristics of airfoil at a low Reynolds number. Chinese Journal of Aeronautics, 28(4), 1003-1015.