Evaluation of wing vortex behavior at high angles of attack by using laser visualization and numerical method

Document Type : Research Paper

Authors

Abstract

In this study, the vertical flow on a sharp edged, 70 degrees swept back delta wing was experimentally investigated in a smoke tunnel, using laser sheet technique. Previous studies show that changing Reynolds number has little effect on the vortex structure of sharp edged delta wings, although the angle of attack has the major effect. Furthermore, Spalart Almaras model is used for numerical investigation on the delta wing. The effect of angle of attack on size and break-down location of the vortices on the wing was studied. The results show that increasing of the angle of attack increases the size of the vortices and the height of the vortex core to the wing surface as well. The bigger vortex on a delta wing leads to increasing the lift of the wing and it increases the maneuverability of the aircraft. Abrupt changes occur in the structure of the vortices at very high angles of attack which is designated as vortex break-down. The vortex break-down cause’s intense oscillation of the surface pressure of the wing and it decreases the aircraft maneuverability.

Keywords

Main Subjects

References

[1] Nangia, R. K. “Semi-Empirical Prediction of Vortex Onset & Progression on 65 Delta Wings RTO-AVT-113.” AIAA, 2008, 384.
[2] Munro, C. D., P. Krus. “Implications of Scale Effect for the Prediction of High Angle of Attack Aerodynamics.” Progress in Aerospace Sciences 41, 2005, pp. 301-322.
[3] Luckring, J. “A Survey of Factors Affecting Blunt Leading-Edge Separation for Swept and Semi-Slender Wings.” AIAA, 2010, 4820.
[4] Dutta, S., K, Muralidhar, K. “Influence of the orientation of a square cylinder on the wake properties.” Experiments in Fluids 34, 2003, pp. 16-23.
[5] Pashilkar, A. “Surface Pressure Model for Simple Delta Wings at High Angles of Attack.” Sadhana Vol. 26, Part 6, 2001, pp. 495-515.
[6] سلطانی، محمدرضا، علیرضا داوری. "بررسی تجربی جریان روی یک بال با ضریب منظری پایین." استقلال، س. 20، ش. 2، 1380.
[7] سلطانی، محمدرضا، علیرضا داوری. "بررسی تجربی گردابه‌های به‌وجود آمده روی بال های مثلثی." شریف، ش. 19، س. 17، 1380.
[8] Lowson, M. V. “Visualization Measurements of Vortex Flows.” Journal of Aircraft, Vol. 28, No. 5, 1991, pp. 320-327.
[9] سلطانی، محمدرضا، احمد شرفی، مجتبی دهقان منشادی. "بررسی میدان سرعت حول یک ترکیب بال - کانارد با استفاده از روش­های تجربی و شبکة عصبی." شریف، ش. 46، س. 24، 1387.
[10] فیضیان، مهدی، مجتبی دهقان منشادی، مهرداد بزاززاده، مهدی ایل بیگی. "مطالعة جریان گردابه­ای و تأثیر زاویة تیزی لبة حملة بال مثلثی با آشکارسازی دود." دوازدهمین کنفرانس انجمن هوافضای ایران، تهران، 1391.
[11] Payne, F. M., K. D. Visser. “Leading edge vortex flow studies at the University of notre dame steady and unsteady investigations.”1983-2000.
[12] Verhaagen, N. G., B. C. Van Bossuyt. “Flow on a 65-Deg Blunt Apex.” AIAA, 2006-3005.
[13] Huang, X. Z. “Critical Assessment of Test Cases on Vortex Breakdown over Slender Delta Wings under Static Model Conditions.” RTO-TR-AVT-080, 2009.
Aerospace Knowledge and Technology Journal
Volume 4, Issue 2 - Serial Number 2
January 2016
Pages 21-33

Files

Share

How to cite

Statistics