Aerodynamic Performance Studies with a Trailing Edge Jet Flap

2013 ◽  
Author(s):  
Ibraheem AlQadi ◽  
Mahmood Khalid ◽  
Salah Hafez
Keyword(s):  
Performance Studies ◽  
Aerodynamic Performance ◽  
Trailing Edge

Geometry and Aerodynamic Performance of Parabolic Trailing-Edge Flaps

2018 ◽  
Author(s):  
Douglas F. Hunsaker ◽  
Jackson T. Reid ◽  
Bruno Moorthamers ◽  
James J. Joo
Keyword(s):  
Aerodynamic Performance ◽  
Trailing Edge ◽  
Trailing Edge Flaps

scholarly journals Features of owl wings that promote silent flight

2017 ◽  
Vol 7 (1) ◽  
pp. 20160078 ◽  
Author(s):  
Hermann Wagner ◽  
Matthias Weger ◽  
Michael Klaas ◽  
Wolfgang Schröder
Keyword(s):  
Noise Reduction ◽  
Leading Edge ◽  
Aerodynamic Performance ◽  
Wing Loading ◽  
Trailing Edge ◽  
Future Directions ◽  
Trailing Edge Noise ◽  
Aerodynamic Properties ◽  
Morphological Adaptations ◽  
Noise Production

Owls are an order of birds of prey that are known for the development of a silent flight. We review here the morphological adaptations of owls leading to silent flight and discuss also aerodynamic properties of owl wings. We start with early observations (until 2005), and then turn to recent advances. The large wings of these birds, resulting in low wing loading and a low aspect ratio, contribute to noise reduction by allowing slow flight. The serrations on the leading edge of the wing and the velvet-like surface have an effect on noise reduction and also lead to an improvement of aerodynamic performance. The fringes at the inner feather vanes reduce noise by gliding into the grooves at the lower wing surface that are formed by barb shafts. The fringed trailing edge of the wing has been shown to reduce trailing edge noise. These adaptations to silent flight have been an inspiration for biologists and engineers for the development of devices with reduced noise production. Today several biomimetic applications such as a serrated pantograph or a fringed ventilator are available. Finally, we discuss unresolved questions and possible future directions.

scholarly journals Aerodynamic Performance of the Inboard Elevon on a Blendedwing- Body Aircraf

2021 ◽  
Author(s):  
Alexander Gordon Jackson
Keyword(s):  
Computational Model ◽  
Numerical Solutions ◽  
Aerodynamic Performance ◽  
Aerodynamic Design ◽  
Trailing Edge ◽  
Negative Deflection ◽  
Average Change ◽  
Implicit Solver ◽  
Blended Wing Body ◽  
Beveled Trailing Edge

The objectives of this research are to examine the effects of trailing edge modifications of the inboard elevon of a blended-wing-body (BWB) aircraft, the goal being to try and reduce the hinge moment of the inboard elevon through selective aerodynamic design. A computational model was built for 60⁰ and 70⁰ beveled trailing edge modifications, as well as no modification. The inboard elevon was deflected positive 5⁰ and negative 5⁰. The numerical solutions were obtained using an implicit solver and inviscid model. The results of this research showed that, through the use of a beveled trailing edge on the inboard elevon, a maximum of 112% reduction in the hinge moment could be achieved for the negative deflection case and a maximum of 88% reduction in the hinge moment for the positive deflection case. The results showed that there was a significant improvement in the hinge moments, with less that a 2% average change in the overall aerodynamic performance of the BWB for the inviscid models.

scholarly journals LETR: An End-to-End Detector of Reconstruction Area in Blade’s Adaptive Machining with Transformer

2022 ◽  
Author(s):  
Zikai Yin ◽  
Yonghou Liang ◽  
Junxue Ren ◽  
Jungang An ◽  
Famei He
Keyword(s):  
Activation Function ◽  
Aerodynamic Performance ◽  
Image Features ◽  
The Self ◽  
Test Results ◽  
Baseline Model ◽  
Trailing Edge ◽  
Reconstruction Process ◽  
Mixed Frequency ◽  
Adaptive Machining

In the leading/trailing edge’s adaptive machining of the near-net-shaped blade, a small portion of the theoretical part is retained for securing aerodynamic performance by manual work. However, this procedure is time-consuming and depends on the human experience. In this paper, we defined retained theoretical leading/trailing edge as the reconstruction area. To accelerate the reconstruction process, an anchor-free neural network model based on Transformer was proposed, named LETR (Leading/trailing Edge Transformer). LETR extracts image features from an aspect of mixed frequency and channel domain. We also integrated LETR with the newest meta-Acon activation function. We tested our model on the self-made dataset LDEG2021 on a single GPU and got an mAP of 91.9\%, which surpassed our baseline model, Deformable DETR by 1.1\%. Furthermore, we modified LETR’s convolution layer and named the new model after GLETR (Ghost Leading/trailing Edge Transformer) as a lightweight model for real-time detection. It is proved that GLETR has fewer weight parameters and converges faster than LETR with an acceptable decrease in mAP (0.1\%) by test results.

scholarly journals The Effect of Gurney Flap and Trailing-edge Wedge on the Aerodynamic Behavior of an Axial Turbine Blade

2021 ◽  
Vol 2 (4) ◽  
pp. 293-305
Author(s):  
Mohammad Mahdi Mahzoon ◽  
Masoud Kharati-Koopaee
Keyword(s):  
Angle Of Attack ◽  
Vortex Generator ◽  
Aerodynamic Performance ◽  
Trailing Edge ◽  
Blunt Trailing Edge ◽  
Gurney Flap ◽  
Maximum Increment ◽  
Lift And Drag ◽  
Lift And Drag Coefficient

In this research, the effect of Gurney flap and trailing-edge wedge on the aerodynamic behavior of blunt trailing-edge airfoil Du97-W-300 which is equipped with vortex generator is studied. To do this, the role of Gurney flap and trailing-edge wedge on the lift and drag coefficient and also aerodynamic performance of the airfoil is studied. Validation of the numerical model is performed by comparison of the obtained results with those of experiment. Results show that before stall, Gurney flap leads to the increase in the aerodynamic performance in a wider range of angle of attack. Numerical findings reveal that the maximum increment for the aerodynamic performance is obtained at low angle of attack when trailing-edge wedge is employed. It is found that for the highest considered value of Gurney flap and trailing-edge wedge heights, where the highest values for the lift occur, the higher aerodynamic performance at low angle of attack is obtained when trailing-edge wedge is used and at high angle of attack, the Gurney flap results in a higher aerodynamic performance. It is also shown that when high aerodynamic performance is concerned, addition of Gurney flap to the airfoil leads to the higher value for the lift. Doi: 10.28991/HIJ-2021-02-04-03 Full Text: PDF

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