{"title":"Dynamic Stall Vortex Formation of OA-209 Airfoil at Low Reynolds Number ","authors":"Aung Myo Thu, Sang Eon Jeon, Yung Hwan Byun, Soo Hyung Park","volume":86,"journal":"International Journal of Aerospace and Mechanical Engineering","pagesStart":267,"pagesEnd":271,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/9997364","abstract":"<p>The unsteady flow field around oscillating OA-209 airfoil at a Reynolds number of 3.5&times;105 were investigated. Three different reduced frequencies were tested in order to see how it affects the hysteresis loop of an airfoil. At a reduced frequency of 0.05 the deep dynamic stall phenomenon was observed. Lift overshooting was observed as a result of dynamic stall vortex (DSV) shedding. Further investigation was carried out to find out the cause of DSV formation and shedding over airfoil. Particle image velocimetry (PIV) and CFD tools were used and it was found out that dynamic stall separation (DSS), which is separated from leading edge separation (LES) and trailing edge separation (TES), triggered the dynamic stall vortex (DSV).<\/p>\r\n","references":"[1]\tSang Eon Jeon, Soo Hyung Park, Yung Hwan Byun, Kai Richter, Wolfgagn Geissler, \"Numerical investigation of boundary layer separation over an airfoil during dynamic stall,\u201d European Rotorcraft Forum 2012, 4-6 September 2012, Amsterdam, Netherland.\r\n[2]\tKobra Gharali, Mingyao Gu, David A. Johnson, \"A PIV Study of a low Reynolds number pitch oscillating SD7037 Airfoil in dynamic stall with CFD comparison\u201d, 16th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 9-12 July, 2012, Lisbon, Portugal.\r\n[3]\tShengyi Wang, Derek B. Ingham, Lin Ma, Mohamed Pourkashanian, Zhi Tao, \"Turbulence modeling of deep dynamic stall at relatively low Reynolds number\u201d. Journal of Fluids and Structures, 2012. B. Smith, \"An approach to graphs of linear forms (Unpublished work style),\u201d unpublished.\r\n[4]\tW. J. McCroskey, \"The phenomenon of dynamic stall\u201d, NASA TM81264, 1981.\r\n[5]\tW. Geissler, Dietz, G., Mai, H., Bosbach, J., and Richard, H., \"Dynamic stall and its passive control investigation on the OA209 airfoil section,\u201d 31st European Rotorcraft Forum, Florence, Italy, September, 2005.\r\n[6]\tW. Geissler, Haselmeyer, H., \"Investigation of dynamic stall onset,\u201d Aerospace Science and Technology, Volume 10, Issue 7, October, 2006.\r\n[7]\tR.Langtry, F.R.Menter, \"Correlation based transition modeling for unstructured parallelized computational fluid dynamics codes,\u201d AIAA Journal, Vol.47,No.12,pp.2894-2906,2009.\r\n[8]\tF.R.Menter, \"Two-equation eddy-viscosity turbulence models for engineering applications,\u201d AIAA Journal, Vol.32, No.8, pp.1598-1605,1994.\r\n","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 86, 2014"}