Comparison of the aerodynamic performance of NACA 4415 and KFm based stepped airfoils

This article presents the aerodynamic characteristics of Kline-Fogleman modified (KFm) airfoil. KFm series airfoil family has better stability and low stalling effects which have made its use for low weight carrying flight. Aerodynamic characteristics have been investigated for KFm-1, KFm-2, and KFm-3 followed by a comparison with NACA 4412 airfoil. Spalart-Allmaras turbulence model is employed on the ANSYS Fluent environment due to the transonic flow condition. The numerical simulation was carried out with varying angle of attacks ranging from 0˚ to 15˚. For a variation of mach number extending from 0.3 to 0.6, the point of separation was resolved to employ CFD analysis. Computational examinations were directed to upgrade the aerodynamic performance of the airfoil. The analyzed results demonstrate the aerodynamic performances in terms of drag and lift coefficients, pressure coefficients, static temperature for the various angle of attacks and mach numbers. Moreover, the numerical result of lift coefficient is compared to the available experimental result in order to validate the carried out numerical simulation. Prevalently the objective of this examination was to numerically decide whether or not the aerodynamic performance of an airfoil can be improved by presenting a retrogressive confronting step on the upper surface of the airfoil.