Abstract
The work investigates the effect of turbulent intensity (T u ) on the force and wake of a NACA0012 airfoil at chord Reynolds number Re c = 5.3 × 103 and 2 × 104. Lift and drag coefficients (C L and C D ) on and flow fields around the airfoil were measured with T u varied from 0.6 to 6.0 %. Four Re c regimes are identified based on the characteristics of the maximum lift coefficient (C L, max), i.e., ultra-low (Re c < 104), low (104 ~ 3 × 105), moderate (3 × 105 ~ 5 × 106), and high (> 5 × 106). It is noted that at Re c = 5.3 × 103 (ultra-low Re c regime) the stall is absent for T u = 0.6 % but occurs for T u = 2.6 and 6.0 %. As Re c increases to low Re c regimes, the T u influence decreases. So does the critical Re c , above which stall occurs. The effect of increasing T u on flow bears similarity to that of increasing Re c , albeit with a difference; the flow separation point shifts upstream with increasing Re c but downstream with increasing T u .
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Acknowledgments
YZ wishes to acknowledge support given to him from Research Grants Council of HKSAR through grant B-Q33J.
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Wang, S., Zhou, Y., Alam, M.M., Yang, H.X. (2014). Turbulent Intensity Effect on Low Reynolds Number Airfoil Wake. In: Zhou, Y., Liu, Y., Huang, L., Hodges, D. (eds) Fluid-Structure-Sound Interactions and Control. Lecture Notes in Mechanical Engineering. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40371-2_29
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DOI: https://doi.org/10.1007/978-3-642-40371-2_29
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