Effect of Attack Angle on Flow around A Square Prism with A Splitter Plate

Öz

Lift and drag forces on a square prism with a (splitter) plate are experimentally investigated by force measurements with a load cell. Results showed that drag and lift coefficients are independent of Reynolds number for Re = 9700 – 36500 at 0°, 45°, 90°, 135° and 180°. Drag coefficient at 0° is obtained as 2.02 for the square prism alone, and 1.04 for the square cylinder with splitter plate. Maximum drag reduction for the square cylinder with the plate is 50% as compared to the square cylinder at 0° and 15°. For α < 30° and α > 114°, drag coefficient of a square prism with splitter plate is smaller than that of the square prism alone. At Re = 20000, lift and drag coefficients significantly change with increasing attack angle.

Anahtar Kelimeler

• Square prism,Splitter plate,Drag coefficient,Lift coefficient

AYIRICI PLAKALI BİR KARE PRİZMA ETRAFINDAKİ AKIŞTA HÜCUM AÇISININ ETKİSİ

Öz

Farklı hücum açılarında akış ayırıcı plakalı bir kare prizmaya etki eden kaldırma ve sürükleme kuvvetleri yük hücresiyle ölçülerek deneysel olarak incelenmiştir. Sonuçlar, kaldırma ve sürükleme katsayılarının Re = 9700 – 36500 aralığında 0°, 45°, 90°, 135° ve 180° hücum açıları için Reynolds sayısından bağımsız olduğunu göstermiştir. Sürükleme katsayısı 0° hücum açısında tek kare prizma için 2.02 ve ayırıcı plakalı kare durumunda ise 1.04 olarak elde edilmiştir. Plakalı kare için maksimum sürükleme katsayısındaki azalma 50% olarak 0° ve 15°’de elde edilmiştir.  α <30° ve α >114° aralıkları için, plakalı karenin sürükleme katsayısı sade karenin sürükleme katsayısından küçüktür. Re = 20000’de, kaldırma ve sürükleme katsayılarının önemli derecede hücum açısına bağlı olarak değiştiği görülmüştür. 

Anahtar Kelimeler

• Kare prizma,Ayırıcı plaka,Sürükleme katsayısı,Kaldırma katsayısı

Kaynakça

1. Akansu, Y. E., Karakaya, F. and Şanlısoy, A. (2013) Active Control of Flow around NACA 0015 Airfoil by Using DBD Plasma Actuator, EPJ Web of Conferences, 45, 1008. doi:10.1051/epjconf/20134501008
2. Akansu, Y. E., Bayindirli, C. and Seyhan, M. (2016) The Improvement of Drag Force on a Truck Trailer Vehicle by Passıve Flow Control Methods. Isı Bilimi ve Teknigi Dergisi-Journal of Thermal Science and Technology 36(1):133–41.
3. Akansu, Y. E., Ozmert, M. and Firat, E. (2011) The Effect of Attack Angle to Vortex Shedding Phenomenon of Flow around a Square Prism with a Flow Control Rod, Isı Bılımı Ve Teknıgı Dergısı-Journal Of Thermal Scıence And Technology, 31(1), 109–120.
4. Akansu, Y. E., Sarioglu, M. and Yavuz, T. (2004) Flow around a Rotatable Circular Cylinder-Plate Body at Subcritical Reynolds Numbers, AIAA Journal, 42(6):1073–80. doi: 10.2514/1.4265.
5. Akbıyık, H., Yahya E. A., Yavuz, H. and Bay, A. E. (2016) Effect of Plasma Actuator and Splitter Plate on Drag Coefficient of a Circular Cylinder, EPJ Web of Conferences, 114, 1051. doi: 10.1051/epjconf/201611402001.
6. Bayındırlı, C. (2017) The Experimental Investigation of the Effects of Spoiler Design on Aerodynamic Drag Coefficient on Truck Trailer Combinations, International Journal of Automotive Engineering and Technologies, 6(0),11–18.
7. Bearman, P. W. and Harvey, J. K. (1993) Control of Circular Cylinder Flow by the Use of Dimples.” AIAA Journal 31(10):1753–56. doi:10.2514/3.11844.
8. Coleman, H. W. and Steele, W. G. (2009) Experimentation, Validation, and Uncertainty Analysis for Engineers, John Wiley & Sons, New Jersey.

9. Fırat, E., Akansu, Y. E. and Akilli, H. (2015) Flow Past a Square Prism with an Upstream Control Rod at Incidence to Uniform Stream, Ocean Engineering, 108, 504–18. doi: 10.1016/j.oceaneng.2015.08.041.
10. Gilarranz, J. L., Traub, L. W. and Rediniotis, O. K. (2005) A New Class of Synthetic Jet Actuators—Part I: Design, Fabrication and Bench Top Characterization, Journal of Fluids Engineering, 127(2), 367-376. doi: 10.1115/1.1839931.
11. Godard, G. and Stanislas, M. (2006) Control of a Decelerating Boundary Layer. Part 1: Optimization of Passive Vortex Generators, Aerospace Science and Technology 10(3), 181–91. doi: 10.1016/j.ast.2005.11.007.
12. Lee, B. E. (1975) The Effect of Turbulence on the Surface Pressure Field of a Square Prism, Journal of Fluid Mechanics, 69(2), 263–82. doi:10.1017/S0022112075001437
13. Li, Z., Navon, I. M., Hussaini, M. Y. and Dimet, F. X. L. (2003) Optimal Control of Cylinder Wakes via Suction and Blowing, Computers and Fluids, 32(2), 149–171. doi: 10.1016/S0045-7930(02)00007-5
14. Vivek, M.and Oosthuizen. P. H. (1990) Effects of Splitter Plates on the Wake Flow behind a Bluff Body, AIAA Journal, 28(5), 778–83. doi:10.1016/S0045-7930(02)00007-5.
15. Rathakrishnan, E. (1999) Effect of Splitter Plate on Bluff Body Drag, AIAA Journal, 37(9), 1125–26. doi:10.2514/2.823.
16. Sarioglu, M. (2017) Control of Flow around a Square Cylinder at Incidence by Using a Splitter Plate, Flow Measurement and Instrumentation, 53, 221–29. doi:10.1016/j.flowmeasinst.2016.06.024.
17. 17. Sarioglu, M., Akansu, Y. E. and Yavuz, T. (2006) Flow Around a Rotatable Square Cylinder-Plate Body, AIAA Journal, 44(5), 1065–72. doi:10.2514/1.18069.
18. Sarioglu, M., Akansu, Y. E. and Yavuz, T. (2005) Control of the Flow around Square Cylinders at Incidence by Using a Rod, AIAA Journal, 43(7), 1419–26. doi:10.2514/1.18069
19. Shimada, K. and Ishihara, T. (2002) Application of a Modified K–Ε Model to the Prediction of Aerodynamic Characteristics of Rectangular Cross-Section Cylinders, Journal of Fluids and Structures, 16(4), 465–85. doi:10.1006/jfls.2001.0433.
20. Tamura, T. and Miyagi, T. (1999) The Effect of Turbulence on Aerodynamic Forces on a Square Cylinder with Various Corner Shapes, Journal of Wind Engineering and Industrial Aerodynamics, 83(1), 135–45. doi:10.1016/S0167-6105(99)00067-7.
21. Volino, R. J. and Mounir B. I. (2012) Separation Control on High Lift Low-Pressure Turbine Airfoils Using Pulsed Vortex Generator Jets, Applied Thermal Engineering, 49, 31–40. doi:10.1016/j.applthermaleng.2011.08.028.
22. Zhang, Y. Y., Huang, D. G., Sun, X. J. and Wu, G. Q. (2010) Exploration in Optimal Design of an Airfoil with a Leading Edge Rotating Cylinder, Journal of Thermal Science, 19(4), 318–25. doi:10.1007/s11630-010-0389-6.