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Sādhanā

, 44:21 | Cite as

Negative lift characteristics of NACA 0012 aerofoil at low Reynolds numbers

  • C Pranesh
  • M SivapragasamEmail author
  • M D Deshpande
  • H K Narahari
Article
  • 13 Downloads

Abstract

Numerical investigations on the flow over NACA 0012 aerofoil are carried out to provide better understanding of the unusual lift characteristics exhibited by this aerofoil at low Reynolds numbers. Computations are carried out at Re = 10,000–100,000, for different values of angles of attack and freestream turbulence intensity. There exists a narrow range of these parameters where the net circulation around this symmetrical aerofoil is negative, leading to the generation of negative lift at positive angles of attack. Different flow regimes are identified and physical explanations are given for this unusual behaviour of negative lift, and the influence of different flow parameters is discussed.

Keywords

NACA 0012 aerofoil low-Reynolds-number flows flow separation transition laminar separation bubble negative lift 

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Copyright information

© Indian Academy of Sciences 2019

Authors and Affiliations

  1. 1.Department of Automotive and Aeronautical EngineeringM S Ramaiah University of Applied SciencesBengaluruIndia

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