Analysis of effects of shape and location of micro-turbulators on unsteady shockwave-boundary layer interactions in transonic flow

• Autorzy: Sznajder J. , Kwiatkowski T.

Identyfikatory

DOI

10.5604/12314005.1213755

• Języki publikacji: EN

Abstrakty

EN

Solutions for turbulisation of a part of laminar boundary layer upstream of shockwave on laminar airfoil in transonic flow were investigated by means of solution of Unsteady Reynolds-Averagd Navier-Stokes equations using as a closure the four-variable Transition SST turbulence model of ANSYS FLUENT solver. This turbulence model has the capability of resolving laminar-turbulent transition occurring in undisturbed flow as well as under the influence of flow-control devices. The aim of the work was to investigate possibilities of improvement of aerodynamic characteristics of laminar wing of a prospective transport aircraft in adverse conditions characterised by occurrence of a shockwave over a laminar-turbulent transition region with separation of laminar flow under the shockwave. The subject is important for application of laminar flow technology, offering economic and environmental advantages due to decreased friction drag, into civil transport aviation. Natural laminar-turbulent transition in the investigated conditions takes place with occurrence of “laminar separation bubble” under the foot of a shockwave and the resulting shockwave is intensive and prone to unsteady oscillations, the “buffet” phenomenon, limiting operational range of flight parameters. In order to counteract the harmful effects of natural laminar-turbulent transition in transonic flow two types of turbulators, placed upstream of the shockwave, were investigated. One of them consisted of delta-shaped vortex generators, producing chordwise-oriented vortices. The other consisted of rectangular micro-vanes, perpendicular to flow and to airfoil surface producing vortices of rotation axes oriented spanwise. Effectiveness of both types of turbulators was investigated for varying height and their location on airfoil chord. Both types of turbulators have proved their effectiveness in tripping laminar boundary layer. The specific effects of the tutbulators, different for each type occurred in the region where laminar separation takes place on clean airfoil. As a result, the changes of lift and drag were different for each type of turbulators.

Słowa kluczowe

EN

transonic flow control; laminar-turbulent transition; flow simulations; aircraft engineering; transport; vehicles

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2016
• Tom: Vol. 23, No. 2
• Strony: 373--380
• Opis fizyczny: Bibliogr. 4 poz., rys.

Twórcy

autor

Sznajder J.

• Institute of Aviation Department of Aerodynamics Krakowska Avenue 110/114, 02-256 Warsaw, Poland tel.: [phone] ext. 492, fax: [phone]

autor

Kwiatkowski T.

• Institute of Aviation Department of Aerodynamics Krakowska Avenue 110/114, 02-256 Warsaw, Poland tel.: [phone] ext. 492, fax: [phone]

Bibliografia

• [1] Langtry, R. B., Menter, F. R., Transition Modeling for General CFD Applications in Aeronautics, AIAA 2005-522, 2005.
• [2] ANSYS FLUENT Theory Guide, ANSYS, Inc., Southpointe October 2012, 275 Technology Drive, Canonsburg, PA 15317.
• [3] Sznajder, J, Kwiatkowski, T., Effects of Turbulence Induced by Micro Vortex Generators on Shockwave – Boundary Layer Interactions, Journal of KONES Powertrain and Transport, Vol. 22, No. 2, 2015.
• [4] Stalewski, W., Sznajder, J., Load Control of Natural-Laminar-Flow Wing Via Boundary Layer Control, Proceedings of VII European Congress on Computational Methods in Applied Sciences and Engineering, June 5-10, Crete, Greece 2016 (in print).

Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę.