Morphing of an adaptive shock control bump using pressurized chambers

The dawn of research on shock and boundary layer interaction control dates back to the 1970s, when humped transonic aerofoils were first studied as a means to improve the performance of supercritical aerofoil technology at off-design conditions. Since then, shock control bumps have been found to be promising devices for such kind of flow control. They have a smearing effect on the shock wave structure achieved through isentropic pre-compression of the flow upstream of the main shock and can significantly lower wave drag without incurring unacceptable viscous losses. However, their performance is strongly dependent on a set of geometrical parameters which must be adjusted according to the ever-changing flight conditions. A concept for an adaptive shock control bump is therefore presented. The proposed actuation mechanism aims at a compact, lightweight and simple structure which could be integrated into the spoiler region of near-future aircraft without major design changes required. Numerical optimization of a simplified analytical model of the structure is used to investigate the shock control bump adaptation to various aerodynamic target shapes. Compromises between geometrical conformity and both structural and actuation related requirements are studied. Furthermore, an outlook is given on design issues related to three-dimensional effects on a finite span shock control bump.

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Optimization and analysis of shock wave/boundary layer interaction for drag reduction by Shock Control Bump

Aerospace Science and Technology ◽

10.1016/j.ast.2015.01.007 ◽

2015 ◽

Vol 42 ◽

pp. 196-208 ◽

Cited By ~ 18

Author(s):

K. Mazaheri ◽

K.C. Kiani ◽

A. Nejati ◽

M. Zeinalpour ◽

R. Taheri

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Drag Reduction ◽

Layer Interaction ◽

Wave Boundary Layer ◽

Shock Control Bump ◽

Shock Control ◽

Boundary Layer Interaction ◽

Wave Boundary

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Making Air Travelling More Economical, An Innovative Drag Reduction Approach For A Supercritical Wing Section Using Shock Control Bumps

Balkan Region Conference on Engineering and Business Education ◽

10.2478/cplbu-2014-0046 ◽

2014 ◽

Vol 1 (1) ◽

pp. 215-220

Author(s):

A Saeed ◽

Malik. S. Raza ◽

Ahmed Mohsin Khalil

Keyword(s):

Drag Reduction ◽

Three Dimensional ◽

Wave Drag ◽

Two Dimensional ◽

Supercritical Airfoil ◽

Shock Control ◽

Wing Section ◽

First Choice ◽

Drag Ratio ◽

Lift To Drag Ratio

AbstractAir travelling is the second largest travelling medium used by people. In future it is expected to be the first choice for the travellers. As increase in the price of oil cost of air travelling is getting higher. Engineers are forced to find the cheaper means of travelling by innovating new techniques. This paper presents the new idea to reduce air travelling cost by reducing drag, which is major driving factor of high fuel consumption. Two-dimensional and three-dimensional shock control contour bumps have been designed and analysed for a supercritical wing section with the aim of transonic wave drag reduction. A supercritical airfoil (NACA SC (02)-0714) has been selected for this study considering the fact that most modern jet transport aircraft that operate in the transonic flow regime (cruise at transonic speeds) employ supercritical airfoil sections. It is to be noted that a decrease in the transonic wave drag without loss in lift would result in an increased lift to drag ratio, which being a key range parameter could potentially increase both the range and endurance of the aircraft. The major geometric bump parameters such as length, height, crest and span have been altered for both the two-dimensional and three-dimensional bumps in order to obtain the optimum location and shape of the bump. Once an optimum standalone three-dimensional bump has been acquired an array of bumps has been manually placed spanwise of an unswept supercritical wing and analysed under fully turbulent flow conditions. Different configurations have been tested with varying three-dimensional bump spacing in order to determine the contribution of bump spacing on overall performance. The results show a 14 percent drag reduction and a consequent 16 percent lift to drag ratio rise at the design Mach number for the optimum arrangement of bumps along the wing span. This innovative technique proves to be a bridge between economical problems and engineering solutions and a milestone for aviation engineering.

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Numerical Study of Three-Dimensional Shock Control Bump Flank Effects on Buffet Behavior

High Performance Computing in Science and Engineering ´15 ◽

10.1007/978-3-319-24633-8_32 ◽

2016 ◽

pp. 495-509 ◽

Cited By ~ 4

Author(s):

R. Mayer ◽

D. Zimmermann ◽

K. Wawrzinek ◽

T. Lutz ◽

E. Krämer

Keyword(s):

Numerical Study ◽

Three Dimensional ◽

Shock Control Bump ◽

Shock Control

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Numerical analysis on shape memory alloy–based adaptive shock control bump

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x18783069 ◽

2018 ◽

Vol 29 (15) ◽

pp. 3055-3066 ◽

Cited By ~ 1

Author(s):

Lin Hao ◽

Jinhao Qiu ◽

Hongli Ji ◽

Rui Nie

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Angle Of Attack ◽

Aerodynamic Characteristics ◽

Wave Drag ◽

Initial Shape ◽

Thermally Activated ◽

Bump Height ◽

Shock Control Bump ◽

Shock Control

A three-dimensional adaptive shock control bump made of shape memory alloy is proposed for transonic wings. The methodology to adaptively change the configuration of the airfoil using the shape memory alloy bump to reduce the shock strength and wave drag is numerically demonstrated using an airfoil RAE2822. The shape memory alloy bump is trained to have a flat initial shape with certain initial strain and can swell up when thermally activated. Boyd–Lagoudas phenomenological model is implemented in finite element method and used to compute the two-dimensional profile and the height of the shape memory alloy bump during thermal activation. The results show that the shape memory alloy bump can generate a considerable deflection due to the reverse phase transformation when thermally activated. The dependence of aerodynamic characteristics of the wing on the height of the shape memory alloy bump and the angle of attack is investigated using computational fluid dynamics method. The results show that there is an optimal bump height for a given angle of attack and the bump with a given height is effective only in certain range of angle of attack. Optimization of bump height and the corresponding driving temperature are carried out under variable angles of attack with the lift-to-drag ratio as the objective function.

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