Faculty Publications
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Item AERODYNAMIC ANALYSIS OF WING WITH LEADING EDGE PROTUBERANCES USING PRANDTL’S LIFTING LINE THEORY(Begell House Inc., 2022) Sathyabhama, A.; Marathe, A.; Rangapure, S.; Potadar, A.The establishment of active or passive flow control techniques over aircraft wings has been an area of continuous effort of experimental as well as theoretical investigations. The passive flow control method of leading edge modification has proven to be effective in improving the lift performance of a wing. Extensive performance analysis of sinusoidal tubercles and the wavy wing has been conducted in the literature. This work aims to determine whether other leading edge geometric modifications like square and triangular protrusions similar to sinusoidal tubercles can provide the same effects. The aerodynamic performance of the wings with sinusoidal, square, and triangular tubercles with amplitudes of 3 mm, 5 mm, 7 mm, and 9 mm and wavelengths of 8 mm, 16 mm, 32 mm, and 64 mm is investigated using Prandtl’s lifting line theory. The effect of wavelength and amplitude variation on lift coefficient (CL) and coefficient of induced drag (CDi) is studied within the prestall regime. The results have shown that CL and CDi reduce and the ratio of these coefficients (CL/CDi) improves for the tubercled wing when compared to the baseline wing. The effect of wavelength variation is found to be negligible. In contrast, amplitude variation showed a maximum increase of CL/CDi in the wing with square tubercles, where it reached 305.15 at 1° AoA, for an amplitude of 9 mm. © 2022 by Begell House, Inc.Item NUMERICAL AND EXPERIMENTAL INVESTIGATION INTO THE EFFECT OF LEADING-EDGE PROTUBERANCES ON THE AERODYNAMIC PERFORMANCE OF WIND TURBINE(Begell House Inc., 2025) Sathyabhama, A.; Sinha, R.K.; Reddy, C.J.In this paper, the numerical and experimental analysis of the effect of leading-edge protuberances on the performance of small horizontal axis wind turbines (SHAWT) at low Reynolds number was carried out. The wind turbine blades were designed using the blade element momentum theory (BEMT) with wake rotation. The E216 profile was chosen over other airfoils because, in low Reynolds number flow conditions, it gives a high lift-to-drag ratio. The tubercle shapes employed for the study are slot, triangular, and sinusoidal, and their effects on the performance of wind turbine were compared with baseline turbine as well as among themselves. The flow behavior and the influence of pitch angle on the performance of baseline wind turbine were investigated. The numerical simulations were conducted in ANSYS FLUENT R2021, and the experiments carried out in a low-speed wind tunnel were used to validate the results. The numerical equations were solved using a three-dimensional Reynolds-averaged Navier-Stokes equation with a shear stress turbulence (SST) k-? turbulence model. The output power, torque, and coefficient of power (CP) values for the baseline turbine increased up to 25° pitch angle and afterwards, a decline was seen. The optimum tip-speed ratio (TSR) was also investigated and found to be 2.67. The pitch angle 25° provides the greatest improvement among all pitch angles examined for the same blade profile. Hence, for the study of different-shaped tubercles (triangular, sinusoidal, and rectangular slot) pitch angle of 25° was considered. Sinusoidal tubercles show a greater lift-to-drag (CL /CD) ratio than baseline wind turbines, although there is no substantial difference in CP. Furthermore, the CL /CD for triangular and slotted tubercles is more significant than that of the baseline wind turbine, as is the CP. When all three tubercles are compared, the slot has the highest CP, while the sinusoidal wind turbine has the highest CL /CD. © 2025 by Begell House, Inc.