Comprehensive Studies on the Aerodynamic Characteristics of Subsonic Scarf Inlets

Authors: M. Jegannath, V. Akshaya, B. Arunkumar, G. Lakshmi Soundharya, V. Thenmozhi, S. Varun, V. R. S. Kumar

Abstract:

For scarf inlet design, the primary variable of interest is the circumferential extent over which the extended lower lip is formed. In this paper, an attempt has been made to optimize the aerodynamic shape of a subsonic scarf inlet with aerodynamically shaped center-body with a particular value of the circumferential extent. The parametric analytical studies have been carried out using a Spalart-Allmaras turbulence model. From our preliminary studies, we concluded that for a particular value of circumferential extent, there will be an exact shape of the center-body with certain geometric orientation for the existence of an aerodynamically efficient scarf inlet for modern aircraft engines. This numerical study is a pointer towards for the design optimization of scarf inlets for modern aircraft engines.

Keywords: Aerodynamics of scarf inlets, inlet design, modern aircraft inlets, subsonic scarf inlet.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.2643982

References:

[1] John M. Abbott, “Computational Study of the Aerodynamic Performance of Subsonic Scarf Inlets”. 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit 11 - 14 July 2004, Fort Lauderdale, Florida.
[2] Abbott, J. M., Dietrich, D. A., “Aerodynamic and Directional Acoustic Performance of a Scoop Inlet”, NASA TP-1028, September, 1977.
[3] Abbott, J. M., “Aerodynamic Performance of Scarf Inlets”, AIAA Paper 79-0380, January, 1979.
[4] Abbott, J. M., and Slater, John W., “Computational Study of the Aerodynamic Performance of Three-Dimensional Subsonic Inlets”, AIAA Paper 2001-3886, July 2001.
[5] T. S. Crum, D. E. Yates, T. L. Andrew and N. 0. Stockman., “Low Speed Test Results Of Subsonic, Turbofan Scarf Inlets”. AIAA/SAE/ASME/ASEE 29th Joint Propulsion Conference and Exhibit June 28-30, 1993 / Monterey, CA.
[6] Abbott, J. M., “Aero acoustic Performance of a Scoop Inlet”, AIAA Paper 77-1354, October, 1977.
[7] Brent. A, Miller and John M., “Aerodynamic and acoustic Performance of two choked-flow Inlets under static conditions” National Aeronautics and Space Administration. Washington, D.C. September 1972.
[8] Brent A, Miller, "Experimentally Determined Aero acoustic Performance and Control of Several Sonic Inlets," AIAA Paper 75-1184, Anaheim, Calif., 1975.
[9] James A. Albers, Norbert O. Stockman, and John J. Hirn, “Aerodynamic Analysis of Several High Throat Mach Number Inlets For The Quiet Clean Short-Haul Experimental Engine”. National Aeronautics and Space Administration. Washington, D. C. January 1975.
[10] Howard L, Wesoky, John M. Abbott, James A. Albers, and Donald A. Dietrich., “Low-Speed Wind Tunnel Tests of a 50.8-Centimeter (20-IN) 1.15-Pressure-Ratio Fan Engine Model”. National Aeronautics and Space Administration. Washington, D. C. June 1974.
[11] James A. Albers, “Theoretical and Experimental Characteristics of A 13.97- Centimeter-Diameter Inlet at STOL Takeoff and Approach Conditions”. National Aeronautics and Space Administration. Washington, D.C. June 1973.
[12] Karen A. Deere, Bobby L. Berrier, Jeffrey D. Flamm, Stuart K. Johnson, “Computational study of fluidic thrust vectoring using separation control in a nozzle,” 21st Applied Aerodynamics Conference 23-26 June 2003, Orlando, Florida, AIAA 2003-3803.
[13] Yonghwan Park, Sungtae Kim, Soogab Lee, Cheolung Cheong, “Numerical investigation on radiation characteristics of discrete-frequency noise from scarf and scoop aero-intakes”, Applied Acoustics 69 (2008) 1258–1269.