Applying Passive Method of the Flow-Around Controlling of the Mechanized Wing by the Jet Blowing-Out on the Flap to Enhance Load-Bearing Capacity

Аuthors

Brutyan M. A., Htun Y. ^*

Moscow Institute of Physics and Technology (National Research University), 9, Institutskiy per., Dolgoprudny, Moscow region, 141701, Russia

*e-mail: yetun53@gmail.com

Abstract

As of today, the task of an aircraft load-bearing capacity increasing associated with possible runways stretch limitation seems rather up-to-date. Minimum allowable landing approach speed and, hence, the flight safety depends upon the maximum lift coefficient at the landing mode. It is common knowledge as well that the necessary condition for the flow separation is a presence of the positive pressure gradient. Thus, one of the trends in the research of the wing load bearing properties is the study on suppressing the flow-around separation-type character. In this regard, the development of various active and passive flow-around control methods has become widespread.
Application of active methods for the tearing-off flows controlling requires well-defined energy costs. Implementation of boundary layer control systems opens up wide possibilities for improving the wing aerodynamic characteristics of the modern aircraft. Wing load-bearing properties increasing stems due to the reduction or complete elimination of the flow separation on the deflected flap, which leads to the circulation increase on the wing.
Unlike active methods, the functioning of passive flow control methods does not require the use of additional energy and, as a rule, are easy to use. Passive methods of influencing flow include the use of mechanical and air vortex generators. There are also works on the use of passive methods, which show the effectiveness of using various jet blowing systems to increase the bearing properties of the wing.
In contrast to the active methods, functioning of the passive flow-around control methods does not require employing extra energy and, as a rule, differ by their ease of use. Application of both mechanical and air vortex generators relates to the impact on the flow-around. The works on passive methods application, which demonstrate the effectiveness of various systems of the jets blowing-out are known as well.
The presented article studies a new passive method for controlling the flow of a mechanized wing by the profiled flow channels located discretely along the flap nose. It is demonstrated that this control method is effective both in cruising flight mode and in takeoff and landing mode with a deflected flap. The article presents the results of numerical studies of the application of a passive method for controlling the flow-around of an adaptive wing employing the profiled flow channels located discretely along the nose of the flap. The numerical studies were conducted on a straight wing with a CLARC Y+ profile with a relative thickness of 12% and a chord of b = 0.64 m with ducts for the air blowing onto the upper surface of the flap, as well as without them. The shape of the holes was specially selected to minimize the losses during the passage of air inside the channel and increase the speed of blowing through the nozzle to the upper surface of the flap.
The article demonstrates that the presented passive control method is effective both in cruising flight mode and in takeoff mode with a deflected flap. It has also been found that blowing-out on a deflected flap reduced drag and increased the profile aerodynamic quality. Application of the above-described passive flow-around control method reduces the size (height) of the tear-off zone on the flap, and affects the flow pattern of the main profile as well. In the profiled channel, the airflow, which enters the boundary layer tangentially to the flap upper surface acceleration occurs, it gives it extra energy and contributes thereby to the tear-off zone shifting further downstream.

Keywords:

airfoil with flap profile, passive flow-around control method, jet blowing-out, aerodynamic characteristics of a wing with passive blowing-out onto the flap, CFD methods

References

1.  Standards of airworthiness of NLG 25 transport category aircraft. Moscow: Federal'noe Agentstvo vozdushnogo transporta; 2022. 355 p. (In Russ.).
2.  Brutyan MA, Potapchik AV, Razdobarin AM et al. Jet-type vortex generators impact on take-offand landing characteristics of a wing with slats. Aerospace MAI Journal. 2019;26(1):19-26.
3.  Gubsky VV. Application of adaptive high-lift devices by an light transport airplane. Trudy MAI. 2013(68). URL: https://trudymai.ru/eng/published.php?ID=41737
4.  Brunet V, Dandois J, Verbeke C. Recent onera flow control research on higher-lift configurations. Aerospace Lab. 2013(6):1-12. URL: https://hal.science/hal-01184627v1
5.  Brutyan MA. Problems of controlling the flow of liquid and gas. Moscow: Nauka; 2015. 271 p. (In Russ.).
6.  Petrov AV. Energy methods for increasing wing lift. Moscow: Fizmatlit; 2011. 402 p. (In Russ.).
7.  Motorin EV, Nazarov DV. Influence of the parameters of the blown flat jet on the aerodynamic characteristics of the profile. In: Materialy XXIV Vserossiiskogo seminara “Upravlenie dvizheniem i navigatsiya letatel'nykh apparatov” (June 17-18, 2021; Samara). Samara: Samarckii universitet; 2022, p. 113–116. (In Russ.).
8.  Pavlenko OV, Petrov AV, Pigusov EA. Studies of flow-around of high-lift wing airfoil with combined energy system for the wing lifting force increasing. Aerospace MAI Journal. 2020;27(4):7-20. (In Russ.). DOI: 10.34759/vst-2020-4-7-20
9.  Pavlenko OV, Pigusov EA. The features numerical investigation of the flow around the wing compartment with the system of the jet tangential blowing onto the wing flap. Avtomatizatsiya. Sovremennye tekhnologii. 2018;72(4):166–171. (In Russ.).
10.  Vlasov VA, Zhulev YuG, Nalivaiko AG. Investigation of jet interference with the wing surface. Uchenye zapiski TsAGI. 2001;XXXII(1–2):83–89. (In Russ.).
11.  Konig J, Hansen H, Coustols E et al. New technologies in low speed aerodynamics wind tunnel and flight test demonstrated in AWIATOR. European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS’2004; 24–28 July, 2004; Jyvaskyla), p. 953.
12.  Abbas F, Mahmood F, Babenko VB et al. Influence of vortex generators on the aerodynamic characteristics of the AEROPRAKT A-20 aircraft model. Prikladnaya gidromekhanika. 2012;14(4):47–58.
13.  Meunier M, Brunet V. High-Lift Devices Performance Enhancement Using Mechanical and Air-Jet Vortex Generators. Journal of Aircraft. 2008;45(6):2049-2061. DOI: 10.2514/1.36836
14.  Součková N, Kuklova J, Popelka L et al. Visualization of flow separation and control by vortex generators on an single flap in landing configuration. The European Physical Journal Conferences. 2012. 25:02026. DOI: 10.1051/epjconf/20122502026
15.  Brutyan MA, Volkov AV, Vyshinskii VV et al. Modification of the shape of the vortex generator to increase its efficiency. Uchenye zapiski TsAGI. 2023;LIV(1):20–27. (In Russ.).
16.  Zhulev YuG, Inshakov SI, Makarov VI et al. Possibility of using wall jets to control the flow of wings in a wide range of angles of attack. Uchenye zapiski TsAGI. 1995;XXVI(1-2):59–64. (In Russ.).
17.  Lawford JА, Foster DN. Low-speed wind-tunnel tests оn а wing section with plain leading- and trailing-edge flaps having boundary-layer control bу blowing. Aeronautical Research Council Reports & Memoranda No. 3639; 1969. London: Her Majesty’s Stationery Office, 1970.
18.  Petrov AV, Shelomovskaya VV. Method for calculating the jet pulse coefficient required to eliminate flow separation on the wing profile.  Trudy TsAGI. Issue 1977. Moscow: TsAGI; 1979. 30 p. (In Russ.).
19.  Phelps AE. Aerodynamics of Upper-Surface Blown Flap. STOL Technology Conference. NASA SP-320; 1972, pp. 97110.
20.  Brutyan MA, Ye T, Pavlenko OV. Influence air wetness on the take-off charateristics of the wing airfoil. Trudy MFTI. 2024;16(1):112118. (In Russ.).
21.  Brutyan MA, Ye H, Pavlenko OV. Numerical Study of the Mechanized Wing Profile Flowing-Around Specifics at Takeoff and Landing Modes in a Humid Air. Aerospace MAI Journal. 2024;31(3):7-13. (In Russ.). URL: https://vestnikmai.ru/publications.php?ID=182553
22.  Shih TH, Liou WW, Shabbir A et al. New k-e Eddy-Viscosity Model for High Reynolds Number Turbulent Flows  Model Development and Validation. Computers Fluids. 1995;24(3):227238.
23.  Wolfshtein M. The Velocity and Temperature Distribution in One-Dimensional Flow with Turbulence Augmentation and Pressure Gradient. International Journal of Heat and Mass Transfer. 1969;12(3):301318.