Effect of the wing airfoil shape on the aerodynamics and performance of a jet-trainer aircraft – An optimization approach

Among the key factors in developing the performance of military aircraft are its aerodynamic characteristics and performance. This research presents the effect of shape of the wing airfoil on the aerodynamic characteristics and performance of the popular jet trainer aircraft L-39C. The aerodynamic data of different airfoil shapes were used to determine the aerodynamic characteristics and performance of the L-39C for different airfoil shapes in an effort to optimize the aircrafts aerodynamic and performance. NACA 64A012 airfoil is currently used on the L-39C, however, there may exist many airfoils that may have potential to improve the aerodynamic characteristics and hence the aircraft performance. For this purpose, a group of NACA airfoils are selected, namely, NACA 4412, NACA 2415, NACA 64212 and NACA 64215. Each of these airfoil influences the aerodynamic characteristics of the aircraft and hence its performance. For each airfoil, the aircraft performance in terms of thrust required, power required, and rate of climb at different altitudes and airspeeds are calculated and analysed. The airfoil data were calculated at cruising flight at zero angle of attack to reduce the variables that can affect the calculations. The results of the calculation and analysis showed that NACA 4412 has significant results in terms of aerodynamic characteristics although in terms of aerodynamic performance, the NACA 64A012 and NACA 4412 showed lower thrust required and power required. NACA 4412 has a (C L )max of 1.67, whereas NACA 64A012 has a (C L )max of 1.336, indicating that the airfoil stalled early at higher altitudes. NACA 4412 also showed better results in terms of aerodynamic characteristics compared to the other selected airfoils although NACA 64A012 shows some variance in the results. NACA 4412 and NACA 64A212 have shown to be promising in aerodynamic characteristics and performance where one has its own benefits over the other. Although in the end, NACA 4412 may be recommended for its aerodynamic characteristics and performance.

Design of a small-scale UAV textile wing fluid-structure numerical modelling

This paper depicts the early phase in the research development for an integrated UAV (Unmanned Aerial Vehicle)support system tailored for emergency response actions and remote sensing. The support system is envisioned as an integrated Unmanned Aerial System (UAS) system that consists of one or more ultralight multifunctional aerial units with a configuration that can be adapted to the nature of the intervention: monitoring, mapping, observation, logistics etc. These aerial units comprise of para-motor type UAVs that use textile paraglider wings of a special design. The overall development and theoretical design aspects that are involved in this research is subject of change been part of an ongoing research study. Starting from wing airfoil and material selection, a design phase is under development for a single sail paraglider wing that can meet the operational demands for the envisioned system. The wing is designed mainly to have an easy handling, predictable deployment at all times and good aerodynamic characteristics. The paper tackles in particular the stretch effect on the wing and the influence on these aerodynamic characteristics as well as means of minimizing the adverse effects.

Design of Low Altitude Long Endurance Solar-Powered UAV Using Genetic Algorithm

This paper presents a novel framework for the design of a low altitude long endurance solar-powered UAV for multiple-day flight. The genetic algorithm is used to optimize wing airfoil using CST parameterization, along with wing, horizontal and vertical tail geometry. The mass estimation model presented in this paper is based on structural layout, design and available materials used in the fabrication of similar UAVs. This model also caters for additional weight due to the change in wing airfoil. The configuration is optimized for a user-defined static margin, thereby incorporating static stability in the optimization. Longitudinal and lateral control systems are developed for the optimized configuration using the inner–outer loop strategy with an LQR and PID controller, respectively. A six degree-of-freedom nonlinear simulation is performed for the validation of the proposed control scheme. The results of nonlinear simulations are in good agreement with static analysis, validating the complete design process.

Theoretical and practical aspects of the design phase for a single skin textile wing

This paper depicts the early phase in the research development for an integrated support system tailored for emergency response actions and remote sensing. The support system is envisioned as an integrated Unmanned Aerial System (UAS) system that consists of one or more ultralight multifunctional aerial units with a configuration that can be adapted to the nature of the intervention: monitoring, mapping, observation and logistics etc. These aerial units comprise of para-motor type UAVs that use textile paraglider wings of a special design. The paper summarizes the basic materials used in the construction of parachutes, as well as it depicts the design phase for the main material used on the wing construction. Starting from wing airfoil and materials selection, a design phase is ongoing for a single sail paraglider wing that can meet the operational demands for emergency response situations. The wing is designed mainly to have an easy handling and to have a predictable deployment at all times. The entire system and the aerial units are designed with increased modularity in order to be tailored for specific operational requirements of the intervention. A numerical model is under development and rigorous testing to validate the theoretical aspects and the design choices.

The Reynolds number and flaperon deflection influence taken into account when optimizing the wing airfoil of an unmanned aerial vehicle

The paper considers the solutions to the multicriteria problem of optimizing the wing airfoil of a miniature unmanned aerial vehicle (MUAV) under various constraints. The study introduces the statement of the problem of multicriteria optimization of the airfoil shape, following the condition of MUAV horizontal flight, with an additional condition associated with a change in the flight Reynolds number of the MUAV wing. This statement of the problem allows us to optimize the airfoil, taking into account the load on the wing of the designed vehicle. The wing airfoil was optimized in a wide range of lift coefficients of Cya and Reynolds numbers. The study shows that taking into account the Reynolds number makes it possible to improve the quality of the result obtained during optimization, and introduces a technique for multicriteria optimization of the wing airfoil with sealed mechanization, i.e. with flaperon. Findings of research show that for equal values of the relative thickness, the mechanized airfoil obtained as a result of optimization has a lower center line camber (by 1.5%) than the optimized airfoil without mechanization, due to which a gain in the drag coefficient is achieved at close to zero values of the lift coefficient. The study shows how profitable the use of a wing airfoil with a flaperon on MUAV wings can be, in contrast to an airfoil without mechanization.

A Review on Applications and Effects of Morphing Wing Technology on UAVs

Unmanned aerial vehicles (UAVs) have excelled with their ability to perform the intended task on or without personnel. In recent years, UAVs have been designed for civilian purposes as well as military applications. Morphing wings are changeable wing applications developed as a result of the need for a different lift and drag forces in various phases of the flight of aircraft. It is an application that enables altering the wing aspect ratio, wing airfoil, wing airfoil camber ratio, wing reference area and even different angles of attack are obtained in different parts of the wing. Although morphing wing application has just begun on today’s UAVs, modern airliners already have morphing wingtip devices such as Boeing 777-X’s. The benefits of the use of morphing wings for UAVs make this technology important. UAVs with morphing wing technology; may increase its payload ratio, may achieve a shorter take-off distance, may land and stop in shorter distance, may take-off where runway clearance is limited, has more efficient altitude change at lower engine RPMs, can obtain higher cruise speeds, may decrease its stall speed, may lower its drag if necessary, thus; saving energy and time. This study concludes a review of literature over morphing wing technology.

Comparative Study of Forward Wingtip Fence and Rearward Wingtip Fence on Wing Airfoil Eppler E562

The perfect wing is a dream that many airplanes has manufactured have been striving to achieve since the beginning of the airplane design. There are some aspect that most influence in aircraft design lift, drag, thrust, and weight. The combination of these aspects leads to a decrease in fuel consumption, which reduces pollution in our atmosphere and increase in economic revenue. One way to improve aircraft performance is to modify the tip of the wing geometry, which has become a common sight on today’s airplanes. With computational programs, the effects on drag due to wingtip devices can be previewed. This research was done numerically by using turbulence model k-ω SST. Reynolds number in this research was 2,34 x 10 4 with angle of attacks are 0o, 2o, 4o, 6o, 8o, 10o, 12o, 15o, 17o and 19o. The model specimen is wing airfoil Eppler 562 with winglets. Two types of wingtips are used: forward and rearward wingtip fence. From this study, it was found that wingtip fence reduced the strength of vorticity magnitude on the x axis compared to plain wings. The leakage of fluid flow effect at the leading edge corner of the wingtip, giving pressure gradient and slightly shifting towards the trailing edge. this occurs in the plain wing and rearward wingtip fence but does not occur in the forward wingtip fence..