Drag reduction and flow structures of wing tip sails in ground effect

Zhou, Jian-xun; Sun, Chenghong; Daichin,

doi:10.1007/s42241-020-0006-4

Cited by 9 publications

(6 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Extensive researches on "wingtip sails" are studied for mimicking slotted wingtip where such applications are feasible in practical applications like transport planes as well as ground effect vehicles [40][41][42][43][44][45][46][47][48][49][50][51][52]. Similar to the slotted wing, Spillman [40] put forward the concept of "wingtip sails", that is, a plurality of thin pieces installed at the tip of the wing.…”

Section: Engineering Applications Of Wingtip Slotsmentioning

confidence: 99%

“…Large aquatic birds, like pelicans, can glide over the water with the help of separate primary feathers to catch fish. Inspired by this, Sun et al [51,52] experimentally studied the aerodynamic properties of ground-effect aircraft with wingtip sails (Fig. 36).…”

Section: Engineering Applications Of Wingtip Slotsmentioning

confidence: 99%

“…35 NACA0012 wing mounted with three wingtip sails [49] Fig. 36 Wings equipped with long tip sails and short tip sails [52] Fig. 37 Three views of "U.S. Marine Corps Dragon Eye UAV" configuration with bionic multiple winglets [56] weight to the device itself [66][67][68].…”

Section: Basic Theories Of Induced Drag and Wingtip Devicesmentioning

confidence: 99%

See 2 more Smart Citations

A Brief Review on Aerodynamic Performance of Wingtip Slots and Research Prospect

et al. 2021

View full text Add to dashboard Cite

Wingtip slots, where the outer primary feathers of birds split and spread vertically, are regarded as an evolved favorable feature that could effectively improve their aerodynamic performance. They have inspired many to perform experiments and simulations as well as to relate their results to aircraft design. This paper aims to provide guidance for the research on the aerodynamic mechanism of wingtip slots. Following a review of previous wingtip slot research, four imperfections are put forward: vacancies in research content, inconsistencies in research conclusions, limitations of early research methods, and shortage of the aerodynamic mechanism analysis. On this basis, further explorations and expansion of the influence factors for steady state are needed; more attention should be poured into the application of flow field integration method to decompose drag, and evaluation of variation in induced drag seems a more rational choice. Geometric and kinematic parameters of wingtip slot structure in the unsteady state, as well as the flexibility of wingtips, should be taken into account. As for the aerodynamic mechanism of wingtip slots, the emphasis can be placed on the study of the formation, development, and evolution of wingtip vortices on slotted wings. Besides, some research strategies and feasibility analyses are proposed for each part of the research.

show abstract

Section: Engineering Applications Of Wingtip Slotsmentioning

confidence: 99%

Section: Engineering Applications Of Wingtip Slotsmentioning

confidence: 99%

See 1 more Smart Citation

A Brief Review on Aerodynamic Performance of Wingtip Slots and Research Prospect

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The shedding of vortices plays a dominant role in the reduction of lift induced drag values along with the ground effect. This can be seen in soaring seabirds like the pelican and the albatross [18] [19]. The stability and control of an aircraft are adversely affected at lower values of speed.…”

Section: B Control Surfaces and Aerofoil Characteristicsmentioning

confidence: 99%

Thermal Soaring and Control Surface Dynamics of an Eagle and the Hummingbird’s Flapping Flight Aerodynamics

Dutta¹,

Chaugule²

2022

IJRASET

View full text Add to dashboard Cite

This review tends to shed light on the eagle’s aerodynamic attributes along with its inbuilt structural control surfaces that facilitate its high maneuverability. Apart from this, few aspects of the eagle’s wing morphing techniques, its aerofoil, and its aerodynamic stability are also being highlighted. The aim is to highlight the bio-mimicable traits of an eagle which can be incorporated into bionic UAVs. This work acts as a base for current and future works involving slotted wingtips and bionic control surfaces. The traits discussed are being used to design mechanical control surfaces and wingtips that resemble the eagle’s slotted wings and control surfaces. These works when combined with compliant mechanisms can help improve roll and yaw control of a UAV along with drag reduction. This review also highlights the aerodynamics of flapping; specifically of the hummingbird. From the hummingbird’s aerodynamics to its hovering techniques; all of its main features are being highlighted. These birds have demonstrated a wide range of aerodynamic traits which if mimicked to near perfection could pave the way for new-age drones. Maneuverability and enhanced aerodynamic optimality could be the outset of extreme sustainability measures with these birds paving the way with their evolutionary flight measures. Apart from their aerodynamic traits, a few aspects of their wing morphing techniques and their evolutionary hereditary traits are also being highlighted.

show abstract

“…Base pressure control plays a significant role in the minimization of base drag. The urge to control this has inspired many studies on abruptly extended flows [2][3][4]. Passive control techniques have always fascinated researchers since they provide expected outcomes without the requirement of any specific systems, as opposed to active control.…”

Section: Introductionmentioning

confidence: 99%

Experimental investigation of suddenly expanded flow at sonic and supersonic Mach numbers using semi-circular ribs: a comparative study between experimental, single layer, deep neural network (SLNN and DNN) models

et al. 2023

View full text Add to dashboard Cite

In this work, we present the findings of the experimental study conducted in a rectangular duct at sonic and supersonic Mach numbers using passive control in the form of semi-circular ribs. Tests are conducted at sonic Mach number and four supersonic Mach numbers. The supersonic Mach numbers of the study are 1.5, 1.8, 2.2, and 2.5. The flow from the nozzles is discharged into the enlarged duct. The ribs are placed at 28 mm (1D), 56 mm (2D), 84 mm (3D), and 112 mm (4D) from the base to find the effect of the control mechanism on the flow field and the base pressure. The ribs of 6, 8, and 10 mm diameter are used to control the base pressure and ultimately the base drag. At Mach 2.2 and 2.5, control is not effective because the nozzles are over-expanded. These results reiterate the findings from the literature that the control is effective whether passive or active when nozzles flow under the influence of a favorable pressure gradient. The same is evident from the results at Mach 1.5 and 1.8. The NPRs at these Mach numbers are such that nozzles are under, correctly, and under expanded. When nozzles are operated for under expanded case, the control results in an increase in the base pressure when passive control is employed. These highly complex data are predicted using a single-layered neural network and a deep-layer neural network to save time and make it cost-effective, which shows that the data can be predicted with an accuracy of 0.88–0.99. The proposed models can predict the highly sensitive pressure terms for aerodynamic flows.

show abstract

Drag reduction and flow structures of wing tip sails in ground effect

Cited by 9 publications

References 13 publications

A Brief Review on Aerodynamic Performance of Wingtip Slots and Research Prospect

A Brief Review on Aerodynamic Performance of Wingtip Slots and Research Prospect

Thermal Soaring and Control Surface Dynamics of an Eagle and the Hummingbird’s Flapping Flight Aerodynamics

Experimental investigation of suddenly expanded flow at sonic and supersonic Mach numbers using semi-circular ribs: a comparative study between experimental, single layer, deep neural network (SLNN and DNN) models

Contact Info

Product

Resources

About