Optimal Design of a Smart Conformable Rotor Airfoil

2002 ◽  
Author(s):  
Roberto A. Sarjeant ◽  
Mary Frecker ◽  
Farhan S. Gandhi
Keyword(s):  
Lift Coefficient ◽  
Vibration Reduction ◽  
Active Material ◽  
Optimization Method ◽  
Skin Thickness ◽  
Optimization Approach ◽  
Trailing Edge ◽  
Element Analysis ◽  
Aerodynamic Loads ◽  
Trailing Edge Flaps

An optimization method has been developed for the design of a smart conformable rotor airfoil with distributed piezoelectric actuators. A conformable airfoil is proposed as a substitute for trailing edge flaps used for helicopter vibration reduction by achieving high frequency camber variations. A topology optimization approach is used where the objective is to maximize trailing edge deflection while minimizing airfoil deformations due to aerodynamic loads. Solutions of the design problem are obtained using Sequential Linear Programming coupled with a Finite Element Analysis procedure. Results show good algorithm convergence and satisfactory airfoil deformations. A study of the effects of different active material resources, skin thickness and aerodynamic loads is performed. Changes in lift coefficient are found to be lower than those obtained for an equivalent flap at similar deflection angles, suggesting that larger deflections might be required for vibration reduction purposes.

Trailing-Edge Flaps for Rotor Performance Enhancement and Vibration Reduction

2013 ◽  
Vol 58 (2) ◽  
pp. 1-13 ◽  
Author(s):  
Kumar Ravichandran ◽  
Inderjit Chopra ◽  
Brian E. Wake ◽  
Benjamin Hein
Keyword(s):  
Performance Enhancement ◽  
Vibration Reduction ◽  
Trailing Edge ◽  
Trailing Edge Flaps

Study on Vibration Reduction Design of Steel-Composite Material Hybrid Mounting for Ship Based on Material Selection Optimization

2013 ◽  
Vol 694-697 ◽  
pp. 415-424
Author(s):  
Wei Wang ◽  
Lu Yun Chen ◽  
Yu Fang Zhang
Keyword(s):  
Power Flow ◽  
Optimization Problems ◽  
Material Selection ◽  
Vibration Reduction ◽  
Optimization Method ◽  
Optimization Approach ◽  
Structural Dynamic ◽  
Level Difference ◽  
Design Variables ◽  
Steel Composite

The material selection optimization for vibration reduction design is studied present article. By introducing the stacking sequence hypothesis of metal material, taking into account the power flow level difference and vibration level difference parameter, the mechanical parameters of the material and plies number are defined as design variables, and the mathematical model of structural dynamic optimization based on material selection optimization approach is established. Finally, a naval hybrid steel-composite mounting structure for example, by introducing genetic algorithm, the optimization problems is solved. The numerical results show that the optimization method is effective and feasible.

Performance Studies on a Wind Turbine Blade Section for Low Wind Speeds With a Gurney Flap

2019 ◽  
Vol 141 (11) ◽  
Author(s):  
M. Rafiuddin Ahmed ◽  
Epeli Nabolaniwaqa
Keyword(s):  
Wind Turbines ◽  
Lift Coefficient ◽  
Flow Characteristics ◽  
Trailing Edge ◽  
Wind Speeds ◽  
Gurney Flap ◽  
Trailing Edge Flaps ◽  
Blade Section ◽  
Low Wind Speeds ◽  
Lift And Drag

The flow characteristics and the lift and drag behavior of a thick trailing-edged airfoil that was provided with fixed trailing-edge flaps (Gurney flaps) of 1–5% height right at the back of the airfoil were studied both experimentally and numerically at different low Reynolds numbers (Re) and angles of attack for possible applications in wind turbines suitable for the wind speeds of 4–6 m/s. The flap considerably improves the suction on the upper surface of the airfoil resulting in a higher lift coefficient. The drag coefficient also increased; however, the increase was less compared with the increase in the lift coefficient, resulting in a higher lift-to-drag ratio in the angles of attack of interest. The results show that trailing-edge flaps can improve the performance of blades designed for low wind speeds and can be directly applied to small wind turbines that are increasingly being used in remote places or in smaller countries.

scholarly journals A STUDY OF HIGH LIFT AERODYNAMIC DEVICES ON COMMERCIAL AIRCRAFTS

Aviation ◽  
2020 ◽  
Vol 24 (3) ◽  
pp. 123-136
Author(s):  
Swamy Naidu Venkata Neigapula ◽  
Satya Prasad Maddula ◽  
Vasishta Bhargava Nukala
Keyword(s):  
Lift Coefficient ◽  
Angle Of Attack ◽  
Leading Edge ◽  
Trailing Edge ◽  
High Lift ◽  
Aircraft Wings ◽  
Surface Pressure Distribution ◽  
Trailing Edge Flaps ◽  
Stall Angle ◽  
Kinematic Mechanisms

Aerodynamic performance of aircraft wings vary with flight path conditions and depend on efficiency of high lift systems. In this work, a study on high lift devices and mechanisms that aim to increase maximum lift coefficient and reduce drag on commercial aircraft wings is discussed. Typically, such extensions are provided to main airfoil along span wise direction of wing and can increase lift coefficient by more than 100% during operation. Increasing the no of trailing edge flaps in chord wise direction could result in 100% increment in lift coefficient at a given angle of attack but leading edge slats improve lift by delaying the flow separation near stall angle of attack. Different combinations of trailing edge flaps used by Airbus, Boeing and McDonnel Douglas manufacturers are explained along with kinematic mechanisms to deploy them. The surface pressure distribution for 30P30N airfoil is evaluated using 2D vortex panel method and effects of chord wise boundary layer flow transitions on aerodynamic lift generation is discussed. The results showed better agreements with experiment data for high Reynolds number (9 million) flow conditions near stall angle of attack.

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