Flow Characteristics of an Ultracompact Serpentine Inlet with an Internal Bump
Publication: Journal of Aerospace Engineering
Volume 31, Issue 2
Abstract
An ultracompact serpentine inlet, which contains a compact diffuser as short as 2.3 times the exit diameter, is experimentally and numerically studied. An internal bump is introduced to redistribute the boundary layer flows and suppress the massive flow separation. It is found that two vortex pairs with the same rotating direction appear at the diffuser exit. The abnormal upper vortex pair helps to avoid massive flow separation at the aft part of the diffuser. According to the calculated flow patterns on the symmetry plane, it is found that a small reversed flow region appears near the lee side of the bump. The skin-friction line plots on the top and bottom surfaces indicate that three-dimensional flow separation occurs. Three vortex tubes are obtained in the diffuser by the Q-criterion. The first, which develops along the spanwise direction downstream of the bump, induces the reversed flow. The second and third vortex tubes, which originate from the sides of the top and bottom surfaces of the duct, collect the low-momentum fluids and transport them downstream spirally. At a test Mach number of 0.70, the total pressure recovery is 0.987 and 0.944 at exit Mach numbers of 0.253 and 0.491, respectively.
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Acknowledgments
This work is funded by the National Nature Science Foundation of People’s Republic of China through Grant Nos. 11532007, 11172136, and 11772156.
References
ANSYS version 13.0 [Computer software]. ANSYS, Canonsburg, PA.
Brear, M. J., Warfield, Z., Mangus, J. F., Braddom, S., Paduano, J. D., and Philhower, J. S. (2004). “Flow separation within the engine inlet of an uninhabited combat air vehicle (UCAV).” J. Fluids Eng., 126(2), 266–272.
Gridley, M. C., and Walker, S. H. (1996). “Inlet and nozzle technology for 21st century fighter aircraft.” 96-GT-244, ASME, New York.
Guo, W. R., and Seddon, J. (1983). “The swirl in an s-duct of typical air intake proportions.” Aeronaut. Q., 34(2), 99–129.
Hamstra, J. W., Miller, D. N., Truax, P. P., Anderson, B. A., and Wendt, B. J. (2016). “Active inlet flow control technology demonstration.” Aeronaut. J., 104(1040), 473–479.
Harper, D. K., Leitch, T. A., Ng, W. F., Guillot, S. A, and Burdisso, R. A. (2000). “Boundary layer control and wall-pressure fluctuations in a serpentine inlet.” AIAA Paper 2000–3597, American Institute of Aeronautics and Astronautics, Reston, VA.
Harrison, N. A., Anderson, J., Fleming, J. L., and Ng, W. F. (2013). “Active flow control of a boundary layer-ingesting serpentine inlet diffuser.” J. Aircraft, 50(1), 262–271.
Jirásek, A. (2006). “Design of vortex generator flow control in inlets.” J. Aircraft, 43(6), 1886–1892.
Kirk, A. M., Gargoloff, J. I., Rediniotis, O., and Cizmas, P. (2007). “Numerical and experimental investigation of a serpentine inlet duct.” Int. J. Comput. Fluid Dyn., 23(3), 245–258.
Kumar, V., and Alvi, F. S. (2006). “Use of supersonic high-speed micro jets for active separation control in diffusers.” AIAA J., 44(2), 273–281.
Lee, B. J., and Kim, C. (2007). “Automated design methodology of turbulent internal flow using discrete adjoint formulation.” Aerosp. Sci. Technol., 11(2–3), 163–173.
Menzies, R. D. D. (2002). “Investigation of S-shaped intake aerodynamics using computational fluid dynamics.” Ph.D. thesis, Univ. of Glasgow, Glasgow, Scotland.
Miller, D. N., and Addington, G. A. (2004). “Aerodynamic flowfield control technologies for highly integrated airframe propulsion flowpaths.” 2nd AIAA Flow Control Conf., American Institute of Aeronautics and Astronautics, Reston, VA.
Perry, A. E., and Chong, M. S. (1986). “A series expansion study of the Navier–Stokes equations with applications to three-dimensional separation patterns.” J. Fluid Mech., 173(-1), 207–223.
Rabe, A. C. (2003). “Effectiveness of a serpentine inlet duct flow control scheme at design and off-design simulated flight conditions.” Ph.D. thesis, Virginia Polytechnic Institute and State Univ., Blacksburg, VA.
Reichert, B. A., and Wendt, B. J. (1993). “An experimental investigation of S-duct flow control using arrays of low profile vortex generators.” 31st AIAA Aerospace Sciences Meeting and Exhibit, American Institute of Aeronautics and Astronautics, Reston, VA.
Seddon, J., and Goldsmith, E. L. (1985). Intake aerodynamics, 1st Ed., American Institute of Aeronautics and Astronautics, New York.
Sun, S., and Guo, R. W. (2006). “The serpentine inlet performance enhancement using vortex generator based flow control.” Chin. J. Aeronaut., 19(1), 10–17.
Sun, S., Guo, R. W., and Wu, Y. Z. (2007). “Characterization and performance enhancement of submerged inlet with flush-mounted planar side entrance.” J. Propul. Power, 23(5), 987–995.
Tindell, R. H. (1988). “Highly compact inlet diffuser technology.” J. Propul. Power, 4(6), 557–563.
Tormalm, M. (2014). “Flow control using vortex generators or micro-jets applied in an UCAV intake.” AIAA Science and Technology Forum and Exposition, American Institute of Aeronautics and Astronautics, Reston, VA.
Wallis, V. C., and Burgun, R. (2003). “Advanced propulsion system design and integration for a turbojet powered unmanned aerial vehicle.” AIAA Paper 2003–415, American Institute of Aeronautics and Astronautics, Reston, VA.
Zhou, H. C., Tan, H. J., and Li, X. P. (2009). “Unique design method of subsonic inlet with complex cross-sectional shape.” J. Aerosp. Power, 24(6), 1357–1363.
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Information
Published In
Journal of Aerospace Engineering
Volume 31 • Issue 2 • March 2018
Copyright
©2017 American Society of Civil Engineers.
History
Received: Sep 22, 2016
Accepted: Jul 3, 2017
Published online: Nov 22, 2017
Published in print: Mar 1, 2018
Discussion open until: Apr 22, 2018
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