Characteristics Of Wing Research Articles

Automation of Winglet Wings Geometry Generation for Its Application in TORNADO

The paper outlines an algorithm for the rapid aerodynamic evaluation of winglet geometries using the TORNADO Vortex Lattice Method. It is a very useful tool to obtain a first approximation of the aerodynamic properties and for performing an optimization of the geometry design. The TORNADO tool is used to systematically calculate the aerodynamic characteristics of various wings with wingtip devices. The fast response of the aerodynamic models allows obtaining a set of results in a remarkably short time. Therefore, the development of an algorithm to generate wing geometries with great ease and complex shapes is of vital importance for the mentioned optimization process. The basic outline of the algorithm, the equations defining the wing geometries, and the results for unconventional wingtip devices, such as blended winglets and spiroid winglets, are presented. Finally, this algorithm allows designing a procedure to study the improvement of aerodynamic properties (lift, induced drag, and moment). Some examples are included to illustrate the capabilities of the algorithm.

A Shear-Sliding Rigid-Flexible Coupled Skin Variable-Sweep Wing Design and Heat-Fluid-Structure Multifield Coupling Analysis

The variable-sweep wing is very attractive for cross-speed domain aircraft. The shear-sliding rigid-flexible coupled skin variable-sweep wing and its associated mechanism are designed and optimized. The variable-sweep wing has smooth continuous deformation and rigid-flexible coupling features. The calculation model of the sliding skin patch segmentation strategy is established, and the aerodynamic characteristics of the two-dimensional airfoil before and after the deformation of the wing skin are analyzed. According to the deformation characteristics of sliding skin, the configuration of the associated mechanism is determined, and the kinematic characteristics of the reference points of each skin are calculated. The kinematic simulation verifies the force of the mechanism model at the joint of skin surfaces during the deformation process. Considering the aerodynamic heat at supersonic speed, the heat transfer, heat distribution, and structural thermal modes between the flow field and the skin are calculated based on the finite element method. The dynamic characteristics of the swept wing with different flight speeds and different morphologies are analyzed. The natural frequencies are found to be reduced by about 30% to 50% compared to cold models at supersonic speeds. Based on the results of the thermal fluid-solid coupling calculation, the skeleton structure of the swept wing is optimized, and the skeleton structure with 25% mass reduction and better performance is obtained.

Aerodynamic Performance of an Unmanned Aerial Vehicle Wing For Varied Wing Geometric Parameters

The aerodynamic performance characteristics of a small unmanned aerial vehicle wing are evaluated computationally at a moderate Reynolds number of Re = 2.8 x 105. The flow exhibits laminar-turbulent transition and features a laminar separation bubble that exists for a substantial portion of the wing span. The flow near the wing tip is three-dimensional and exhibits complex flow patterns due to the interaction of the wing tip vortex with the laminar separation bubble. A series of systematic parametric studies are conducted by varying the wing geometric parameters like the span of the rectangular inboard wing, sweep of the outboard wing and wing dihedral angle. From the parametric studies, it is found that the wing with an outboard sweep of 17° has a 4.54 % improvement in endurance factor compared to the baseline wing at an angle of attack of 5°. The drag of this wing is 19.2 drag counts lower compared to the baseline wing. Further, flow transition is delayed for this wing. The present results show that wing sweep has a significant influence on the improvement of aerodynamic performance of unmanned aerial vehicle wings at moderate Reynolds numbers.

Математична модель розрахунку аеродинамічних сил, утворюваних роторним рушієм для пропульсивних крил

The subject of the study is the modeling and obtaining of aerodynamic characteristics and determining the aerodynamic forces acting on an aircraft with a propulsive wing using a mathematical model. The research is based on mathematical methods and proposes a comprehensive model that accurately describes the interaction of airflow with wing and rotor propulsion. The aim of this study is to find solutions for faster calculations and approximate analysis of wings and aircraft that use them, compared to CFD methods. The task is to find methods that can perform calculations based only on geometric shapes and a minimal set of data that can be obtained by the researcher. The article begins with a review of previous research in the field of aerodynamics, demonstrating the need for the development of new models to better understand the aerodynamic forces generated by wing and rotor propulsion. A new mathematical model is considered, using methods based on Bernoulli's equation and taking into account parameters such as wing shape, angle of attack, airflow velocity, and rotor propulsion characteristics. This article describes the mathematical equations and approaches used to model aerodynamic forces. They include physical laws such as Newton's laws, the conservation of mass and momentum, and basic aerodynamic equations. Validation of the model was conducted by comparing the obtained results with experimental data. To verify the correctness of the presented claims, a series of computational experiments using numerical methods are performed to calculate the dynamic characteristics for different wing and rotor propulsion configurations, and the obtained data are compared. Through careful experiments and data analysis, the research results are expected to provide valuable insights into the practical implementation of an integrated tangential fan system in a wing by evaluating its efficiency, limitations, and potential advantages. This work can help engineers determine optimal wing and rotor propulsion configurations to achieve better aerodynamic efficiency and ensure the desired flight characteristics. This research can make an important contribution to the development of aviation technology and to the improvement of aircraft with rotor propulsion. Conclusions: the article proposes a new mathematical model for calculating the aerodynamic forces generated by wing and rotor propulsion and demonstrates its speed and efficiency by comparing it with experimental data. This research is just the first step in creating a mathematical framework. To improve calculation results and enable automation for greater variability in shape, the panel-vortex method with the consideration of flow acceleration over panel surfaces is more suitable. However, even at this stage, the research results can contribute to the development and optimization of aircraft structures with propulsive devices embedded in the wing design.

Aerodynamic Characteristics of a Z-Shaped Folding Wing

Z-shaped folding wings have the potential to enhance the flight performance of an aircraft, contingent upon its mission requirements. However, the current scope of research on unmanned aerial vehicles (UAVs) with Z-shaped folding wings primarily focuses on the analysis of their folding structure and aeroelasticity-related vibrations. Computational fluid dynamics methods and dynamic meshing are employed to examine the folding process of Z-shaped folding wings. By comparing the steady aerodynamic characteristics of Z-shaped folding wings with those of conventional wings, this investigation explores the dynamic aerodynamic properties of Z-shaped folding wings at varying upward folding speeds. The numerical findings reveal that the folding of Z-shaped folding wings reduces the lift-to-drag ratio, yet simultaneously diminishes the nose-down pitching moment, thereby augmenting maneuverability. Concerning unsteady aerodynamics, the transient lift and drag coefficients of the folded wing initially increase and subsequently decrease as the folding angle increases at small angles of attack. Likewise, the nose-down pitching moment exhibits the same pattern in response to the folding angle. Additionally, the aerodynamic coefficients experience a slight decrease during the initial half of the folding process with increasing folding speed. Once the wing reaches approximately 40°~45° of folding, there is an abrupt change in the transient aerodynamic coefficients. Notably, this abrupt change is delayed with higher folding speeds, eventually converging to similar values across different folding speeds.

Determination of Anatolian Honeybee Biodiversity by Wing Characters

In this study, we report that there were five different subspecies and three different ecotypes defined so far in Türkiye, which has a rich biodiversity in terms of honeybee subspecies. However, recently, it has been thought that the current biodiversity is in danger of extinction due to the commercial queen bee supply and the migratory beekeeping activities from a single source. This study uses the morphometric method to reveal the current status of honeybee biodiversity in Türkiye. For this purpose, a total of 3186 worker bees were studied by samplings from 19 different provinces to represent the honeybee races and ecotypes distributed in Türkiye. We made wing preparations and established 19 landmarks on the right forewings using the BAB BsPro200 program. The program automatically obtained the wing’s metrics’ angle, length, and index values via these 19 landmarks. We used Discriminant function analysis to determine intragroup and intergroup variations by taking the colony averages from data obtained from 31 morphological characters. Given the canonical discriminant function analysis and UPGMA dendrogram, Zonguldak, Düzce, Sakarya, Artvin, Ardahan, and Trabzon constituted a group, and Edirne, Kilis, Van, and Isparta formed a separate group. Hakkari, Kahramanmaraş, and Ordu provinces formed a separate line together. On the other hand, the group centers of Kars and Kırklareli, two different ends of Türkiye, overlapped and formed a close line with Isparta. As a result, this study revealed that, although the protection measures taken at the local level effectively protected the honeybee biodiversity, these measures are insufficient.

Flow Field Investigation on a Double Delta Wing

In this paper flow field characteristics of double delta wing have been studied both experimentally and numerically at different angles of attack ranging from 0° to 30° at a Reynolds number of 2 x 10<sup>5</sup> based on the root chord length of the wing model. Surface oil flow visualization has been studied on the leeward surface of a sharp edged single beveled 76°/40° cropped double delta wing at subsonic wind tunnel facility. The flow physics is further validated with the help of surface pressure measurement in the context of surface flow pattern. Subsequently CFD (Computational Fluid Dynamics) analysis is carried out using ANSYS Fluent. Comparisons of both qualitative as well as quantitative measurement with experimental techniques and computational work have been carried out. For computational work, the computational domain is meshed with unstructured grids and SA-turbulence model is used.

Scallop ice shape characteristics of swept wing based on large-scale icing wind tunnel experiment

Scallop ice is a special phenomenon that occurs during swept wing aircraft passing through icing clouds. It poses a great challenge for the icing safety assessment that the complex scallop ice shape feature and its mechanism are still unclear. In this work, a large-scale icing wind tunnel experiment of swept wing designed by NACA0012 airfoil is conducted in the Icing Wind Tunnel of China Aerodynamics Research and Development Center. The detailed three-dimensional ice shapes under 0°, 15°, 30° and 45° swept angles are obtained by laser scanning technology. The experimental results show that with the swept angle increasing from 0° to 45°, the 2D double ice horn structures show certain spanwise variation, and finally transform into complete scallop ice with ice thickness greatly enhanced in the stagnation line region. The empirical mode decomposition of the spanwise ice curve captures the high-frequency fluctuation on the scallop ice caused by the small-scale roughness element, while the trend with low frequency is not obvious. Based on the experimental data, a new complete scallop ice geometric model, named 5Points-5Lines-2Arcs (5P-5L-2A) model, is proposed, which can provide important basis for the quantitative description of complex scallop ice shape.

Descriptive and Geometric Morphometry of the Wings of Phlebotomus sergenti Populations in Central Morocco.

Phlebotomus sergenti, the proven vector of Leishmania tropica, the causative agent of anthroponotic cutaneous leishmaniasis, is widely distributed in Morocco. Previous works using molecular markers (Internal Transcribed Spacer 2 rDNA and Cytochrome B mtDNA) hypothesized the existence of multiple closely related populations of sand fly species (cryptic species) that would exhibit distinct vectorial capacities. This work studies morphotypic diversity using traditional and geometric morphometry analyses carried out on Ph. sergenti's wings from central Morocco, where active L. tropica transmission occurs for 30 years. Descriptive characteristics (size and shape) of the right wings were measured in Ph. sergenti's specimens collected from fourteen stations in central Morocco. Both traditional and geometric morphometry methods were used to analyse geographic variations in Ph. sergenti wing's size and shape. These analyses support the existence of distinct Ph. sergenti populations, enlightening significant phenotypic variations of Ph. sergenti's wings, regarding their size and shape, depending on geographic origin. In addition, traditional and geometric morphometric analyses of the wing's length, centroid size, β, ɵ, and γ distances allowed clear discrimination of Ph. sergenti sub-populations. These data pinpoint the adaptative ability of Ph. sergenti to local environmental conditions. Additional studies are now required to further shed light on the genetic structure of Ph. sergenti populations in Morocco.

Aspect Ratio Effects on the Aerodynamic Performance of a Biomimetic Hummingbird Wing in Flapping.

Hummingbirds are flapping winged creatures with unique flight mechanisms. Their flight pattern is more similar to insects than other birds. Because their flight pattern provides a large lift force at a very small scale, hummingbirds can remain hovering while flapping. This feature is of high research value. In order to understand the high-lift mechanism of hummingbirds' wings, in this study a kinematic model is established based on hummingbirds' hovering and flapping process, and wing models imitating the wing of a hummingbird are designed with different aspect ratios. Therefore, with the help of computational fluid dynamics methods, the effect of aspect ratio changes on the aerodynamic characteristics of hummingbirds' hovering and flapping are explored in this study. Through two different quantitative analysis methods, the results of lift coefficient and drag coefficient show completely opposite trends. Therefore, lift-drag ratio is introduced to better evaluate aerodynamic characteristics under different aspect ratios, and it is found that the lift-drag ratio reaches a higher value when AR = 4. A similar conclusion is also reached following research on the power factor, which shows that the biomimetic hummingbird wing with AR = 4 has better aerodynamic characteristics. Furthermore, the study of the pressure nephogram and vortices diagram in the flapping process are examined, leading to elucidation of the effect of aspect ratio on the flow field around hummingbirds' wings and how these effects ultimately lead to changes in the aerodynamic characteristics of the birds' wings.

Hybrid Laminar Flow Control Optimizations for Infinite Swept Wings

Maintaining the laminar flow on surfaces through active control is a significantly promising technique for reducing fuel burn and alleviating environmental concerns in commercial aviation. However, there is a lack of systematic parameter studies for the hybrid laminar flow control (HLFC) together with natural laminar flow (NLF). To address this need, we optimize the infinite swept wings with different sweep angles and at various conditions, including different Mach numbers, Reynolds numbers, and lift coefficients. The Reynolds-averaged Navier-Stokes (RANS) solver coupled with the linear stability theory is applied for the laminar-turbulent transition prediction, and the traditional optimization method based on evolutionary algorithms is applied for laminar flow wing optimization. The optimization results found that HLFC is required when the NLF fails at a larger sweep angle (35°) and Reynolds number ( 20 × 10 6 ). The lower pressure peak with boundary-layer suction is found to delay the transition of the regional aviation condition. Besides, the pressure distribution of HLFC is similar to NLF results at the lower Reynolds number ( 10 × 10 6 ) or sweep angle (25°), i.e., a gentle negative pressure gradient near the leading edge and a small favorable pressure gradient behind it. Clarifying the characteristics of laminar flow wings will advance the application of the laminar flow technique within its field.

The damselfly genus Furagrion Petrulevičius et al. (Odonata, Zygoptera) from the early Eocene Fur Formation of Denmark and the dysagrionoid grade.

The earliest Eocene odonate genus Furagrion Petrulevičius et al. from the Danish Fur Formation is revised based on eighteen specimens, two of which apparently have been lost since their publication. The holotype of Phenacolestes jutlandicus Henriksen, type species of Furagrion, is incomplete and lacks the characters currently used to differentiate species, genera and higher taxa in Odonata. We, therefore, propose that the holotype is set aside and a recently discovered nearly complete Fur Formation fossil is designated as neotype. Furagrion possesses all of the nine wing character states currently used along with head shape for diagnosing the Dysagrionidae; however, Furagrion has a characteristically zygopteran head, not the distinctive head shape of the suborder Cephalozygoptera. We, therefore, treat it as a zygopteran unassigned to family. These nine wing character states appear in different combinations not only in various Zygoptera and Cephalozygoptera, but also in the Frenguelliidae, an Eocene family of Argentina that may represent an unnamed suborder. We recognise these taxa as constituting a dysagrionoid grade, in which these character states appear either convergently or as symplesiomorphies. Furagrion morsi Zessin is synonymized with Phenacolestes jutlandicus Henriksen, syn. nov. and Morsagrion Zessin with Furagrion Petrulevičius, Wappler, Wedmann, Rust, and Nel, syn. nov.

Dynamic CFD/CSD Coupling Research for Flexible Micro Aircraft

Bio-inspired flapping wing aircraft have made progress in recent years. Flying birds can fly in various low Reynolds numbers (103-105) with high flight stability and maneuvering ability by use of the flexible deformation of skeletal muscle structures or thin-film structure wings. Early studies mainly focused on the aerodynamics and kinematics of the flapping wings, with relatively little research on the flexible structure, and the aerodynamic structure coupling characteristics of micro flappings are still unclear. At present, the focus of research is to evaluate the impact of structural deformation on the aerodynamic characteristics of flexible micro-flapping wing. A CFD/CSD coupling solver are developed and several technical challenges related to the CFD/CSD interface are resolved in this study (CFD/CSD data exchange method and moving mesh generation). The aerodynamic characteristics of five flexible wings with different structural parameters are calculated and compared. The results show that structural parameters play an important role in aerodynamic performance, which also indicates that the potential aerodynamic performance can be improved by the optimal structural design.

Sectional Leading Edge Vortex Lift and Drag Coefficients of Autorotating Samaras

Autorotating samaras such as Sycamore seeds are capable of descending at exceptionally slow speeds and the secret behind this characteristic is attributed to a flow mechanism known as the leading edge vortex (LEV). A stable LEV is known to increase the maximum lift coefficient attainable at high angles of attack and recent studies of revolving and flapping wings have proposed suitable lift and drag coefficient models to characterise the aerodynamic forces of the LEV. For the samara, however, little has been explored to properly test the suitability of these low-order lift and drag coefficient models in describing the aerodynamic forces produced by the samara. Thus, in this paper, we aim to analyse the use of two proposed aerodynamic models, namely, the normal force and Polhamus models, in describing the sectional aerodynamic lift of a samara that is producing a LEV. Additionally, we aim to quantify the aerodynamic parameters that can describe the lift and drag of the samara for a range of wind speed conditions. To achieve this, the study first examined the samara flight data available in the literature, and from it, the profiles of the lift coefficient curves were investigated. Subsequently, a numerical Blade Element-Momentum model (BEM) of the autorotating samara encompassing different lift profiles was developed and validated against a comprehensive set of samara flight data, which were measured from wind tunnel experiments conducted at the University of Bristol for three different Sycamores. The results indicated that both the normal force and Polhamus lift models combined with the normal force drag can be used to describe the two-dimensional lift characteristics of a samara exhibiting an LEV. However, the normal force model appeared to be more suitable, since the Polhamus relied on many assumptions. The results also revealed that the aerodynamic force parameters can vary with windspeed and with the samara wing characteristics, as well as along the span of the samara wing. Values of the lift curve slope, zero-lift drag coefficient, and maximum lift coefficient are predicted and presented for different samaras. The study also showed that the low-order BEM model was able to generate a good agreement with the experimental measurements in the prediction of both rotational speed and thrust. Such a validated BEM model can be used for the initial design of bio-inspired rotors for micro-air vehicles.

Structural Dynamic Characterization of a Modular Morphing Wing Exploiting Finite Elements and Taguchi Methodology

Detrimental environmental impacts due to the increasing demands of the aviation industry have gained tremendous global attention. With a potential fuel saving, along with high aerodynamic performance and maneuverability during different phases of a flight, adaptable wing design has become a viable alternative to its fixed-shape counterpart. A morphing wing design embraces, and can respond accordingly to, most of the flight condition variations effectively and efficiently. Despite these prospects, morphing wing design comes with some challenges due to its inherent complexity caused by an increased number of degrees of freedom. With the availability of various morphing parameters, the vibration signature of a morphing wing design plays a vital role in terms of its structural as well as aeroelastic characteristics. In the present paper, the dynamic characteristics of a re-configurable modular morphing wing developed in-house by a research team at Toronto Metropolitan University are investigated. This modular morphing wing, developed based on the idea of a parallel robot, consists of a number of structural elements connected to each other and to the wing ribs through eyebolt joints. Timoshenko bending beam theories, in conjunction with finite element methodology, are exploited. The free vibration of un-morphed (original) and morphed configurations undergoing multiple levels of sweep and spanwise morphing is presented through a design of experiment methodology.

A new species of Mycomya Rondani, 1856 (Diptera: Mycetophilidae) common to southeast Australia, Tasmania, and New Zealand.

Mycomya quadrimaculata sp. nov. is described from specimens collected in southeast Australia, Tasmania, and New Zealand. A key and type photographs of known Australian and New Zealand Mycomya species are provided. The relative abundance, observed distribution, and morphological affinities of the new species suggests that it is adventive and a recent introduction to New Zealand. Wing characters indicate that the new species is most closely aligned with a subgroup of the Australian Mycomya fauna.

Review of vortex lattice method for supersonic aircraft design

AbstractThere has been a renewed interest in developing environmentally friendly, economically viable, and technologically feasible supersonic transport aircraft and reduced order modeling methods can play an important contribution in accelerating the design process of these future aircraft. This paper reviews the use of the vortex lattice method (VLM) in modeling the general aerodynamics of subsonic and supersonic aircraft. The historical overview of the vortex lattice method is reviewed which indicates the use of this method for over a century for development and advancements in the aerodynamic analysis of subsonic and supersonic aircraft. The preference of VLM over other potential flow-solvers is because of its low order highly efficient computational analysis which is quick and efficient. Developments in VLM covering steady, unsteady state, linear and non-linear aerodynamic characteristics for different wing planform for the purpose of several different types of design optimisation is reviewed. For over a decade classical vortex lattice method has been used for multi-objective optimisation studies for commercial aircraft and unmanned aerial vehicle’s aerodynamic performance optimisation. VLM was one of the major potential flow solvers for studying the aerodynamic and aeroelastic characteristics of many wings and aircraft for NASA’s supersonic transport mission (SST). VLM is a preferred means for solving large numbers of computational design parameters in less time, more efficiently, and cheaper when compared to conventional CFD analysis which lends itself more to detailed study and solving the more challenging configuration and aerodynamic features of civil supersonic transport.

High bypass turbofan engine and anti-icing system performance: Mass flow rate of anti-icing bleed air system effect

Most aircraft are flying at high altitude which can cause icing accumulation, changes the wing profile and the aerodynamic characteristics of wing. The anti-icing bleed air system (AI-BAS) is considered an important system used to prevent the icing accumulation using hot air from engine (bleed); but it may lead to reduced engine performance. This work aims to study the effect of bleed variation on engine performance and (AI-BAS). The bleed air was extracted from the intermediate stage of engine compressor. MATLAB software was used to simulate the engine cycle and estimate performance. The performance of (AI-BAS) was investigated computationally for different bleed air ratio. The computational domain was constructed and solved by ANSYS software for partial span model (PSM) with suitable periodic conditions. The obtained results show that the engine performance characteristics are decreased with increasing of anti-icing bleed air and the overall efficiency of engine is decreased by about 1.29%, 2.63% and 4.01%, for bleed air ratio of 0.02, 0.04 and 0.06 respectively. On the other hand, the average temperature of wing leading edge was increased by about 2.68% and 4.86%, for bleed air ratio of 0.04 and 0.06 respectively compared to the bleed air ratio of 0.02.

Functional Hazard Assessment of a Modular Re-Configurable Morphing Wing Using Taguchi and Finite Element Methodologies

Growing concerns over the CO2 footprint due the exponential demand of the aviation industry, along with the requirements for high aerodynamic performance, cost saving, and manoeuvrability during different phases of a flight, pave the path towards adaptable wing design. Morphing wing design encompasses most, if not all, of the flight condition variations, and can respond interactively. However, functional failure of the morphing wing might bring devastating impacts on the passengers, crew, and/or aircraft. In the present work, the dynamic characteristics of a re-configurable modular morphing wing developed in-house by a research group at the Toronto Metropolitan University, are investigated from the perspective of a functional hazard assessment (FHA). This modular morphing wing, developed based on the idea of a parallel robot, consists of a number of structural elements connected to each other and to the wing ribs through eye-bolt joints. Timoshenko’s bending beam theory, in conjunction with the finite element method (FEM), is exploited to model the structural members. Possible hazards, assumed here to be the structural failure of the beam components, have been identified and their failure conditions are assessed. Numerical simulations have been presented to show the impact of various combinations of the identified hazards on the vibration signature of the morphing wing in unmorphed and morphed configurations. Identification of changes in the wing’s vibration signature is a vital component in the fail-safe structural and aeroelastic design of an aircraft. The present study is geared towards the structural response of the system in the absence of any aerodynamic loads.

A New Flow Control Method of Slat-Grid Channel-Coupled Configuration on High-Lift Device

A slot formed between the slat and the main wing of the 2D high-lift device is used to accelerate the convergence of the flow to the upper surface of the main wing to improve the flow field quality. In order to further enhance flow characteristics, this paper proposes a design method for multi-channel leading-edge slats based on grid flow channels. On the one hand, a specific shape of a shrinking expansion tube is formed to improve the lift characteristics of the leading slat. On the other hand, the newly formed slot plays a similar role to that of the jet stream, delaying the separation on the upper surface of the main wing, making the separation point move back and helping to improve the lift characteristics of the main wing. The optimization of coupled slat-grid channel configuration is developed by using the DOE algorithm. The geometric parameters, such as coordinates and curve slope, are considered as design variables, and the maximum lift–drag ratio is taken as the optimization objective required to obtain the optimal configuration. The simulation and optimization results show that the lift coefficient increases by 3.3%, the drag coefficient decreases by 12.7%, and the lift–drag ratio increases by 18.4% of the optimal configuration compared with the original airfoil at an angle of attack of 16.3°.