Simulation and automation of aluminium panel shot peen forming

We present a methodology for automated forming of metal plates into freeformshapes using shot peening. The methodology is based on a simulation softwarethat computes the peening pattern and simulates the effect of its application.The pattern generation requires preliminary experimental characterizationof the treatment. The treatment is applied by a shot peening robot. The program for the robot is generated automatically according to the peening pattern. We validate the methodology with a series of tests. Namely, we form nine aluminum plates into doubly curved shapes and we also shape model airplane wing skins. The article describes the complete workflow and the experimental results.

Multiagent Control of Airplane Wing Stability with “Feathers” under the Flexural Torsional Flutter

This paper proposes a novel method for the unbounded oscillation prevention of an aircraft wing under the flexural torsional flutter, an innovative multiagent attitude to control an aircraft wing with a surface consisting of managed rotating “feathers” (agents). Theoretical evaluation of the method demonstrates its high aptitude to avoid an aircraft wing’s flexural-torsional vibrations via expansion of the model’s ability to dampen the wing oscillations. It potentially allows increasing an aircraft’s speed without misgiving of the flutter. A new way to control an aircraft wing based on the Speed-Gradient methodology is suggested to increase the maximal possible flight speed without a flutter occurrence. Provided experiments demonstrate the theoretical advantage of the multiagent approach to the “feathers” rotation control.

Numerical modeling on dynamics of droplet in aircraft wing structure at different velocities

Purpose The purpose of this paper is to find the droplets impact on the airplane wing structure. Two kinds of characteristics of the droplet at different velocity and viscosity are assumed. The droplet is assumed to be spherical cubic form and it is injected from the convergent divergent nozzle with a passive control. Design/methodology/approach This paper presents the results of a numerical simulation of droplet impact on the horizontal surface. The effects of impact parameters are studied. The splash effect of the droplet also visualized. The results are presented in form of stress, strain, displacement magnitude of the droplet. Findings Crosswire is used as passive control. The behavior of the droplet impact is observed based on the kinetic energy and the gravitational forces. Originality/value The results predict that smooth particle hydrodynamic designed droplet not only depend on the equation of state of the droplet but also the injection velocity from the nozzle. It also determined that droplet velocity is depending on the viscosity of the fluid.

Optimum PID controller for airplane wing tires based on gravitational search algorithm

In this paper, the gravitational search algorithm (GSA) is proposed as a method for controlling the opening and closing of airplane wing tires. The GSA is used to find the optimum proportional-integral-derivative (PID) controller, which controls the wing tires during take-off and landing. In addition, the GSA is suggested as an approach for overcoming the absence of the transfer function, which is usually required to design the optimum PID. The use of the GSA is expected to improve the system. Two of the most popular optimisation algorithms-the harmony search algorithm (HSA) and the particle swarm optimisation (PSO)-were used for the sake of comparison. Moreover, the GSA-, HSA- and PSO-based optimum PID controllers were compared with one of the most important PID tuning methods, the Ziegler-Nichols (ZN) method. In this study, the integral time absolute error (ITAE) was used as a fitness function. First, four transfer functions for different applications were used to compare the performance of the GSA-based PID (PID-GSA), HSA-based PID (PID-HSA), PSO-based PID (PID-PSO) and Ziegler-Nichols-based PID (PID-ZN). Next, the GSA was used to design the optimum PID controller for the opening and closing systems of the airplane wing tires. The results reveal that the GSA provides better outcomes in terms of ITAE when compared with the other adopted algorithms. Furthermore, the GSA demonstrates a fast and robust response to reference variation.

Desain dan Analisis Tegangan Rangka Alat Simulasi Pergerakan Kendali Terbang Menggunakan Metode Elemen Hingga

Alat simulasi pergerakan kendali terbang merupakan alat peraga untuk menunjukkan mekanisme kerja dari sayap dan ekor pesawat terbang yang mendekati kenyataan. Alat ini bertujuan sebagai metode pembelajaran bagi calon pilot sebelum mengendarai sebuah pesawat terbang. Penelitian ini bertujuan untuk merancang dan menganalisis rangka alat simulasi pergerakan kendali terbang menggunakan metode elemen hingga. Analisis statik dilakukan menggunakan perangkat lunak SolidWorks 2017. Material rangka yang digunakan yaitu baja ASTM A36 dan ASTM A500 (square hollow section) dengan ukuran 50 x 50 x 1,2 mm dan 40 x 40 x 1 mm. Beban yang digunakan yaitu 375,25 kg yang merupakan beban sayap dan ekor pesawat. Hasil analisis menunjukkan rancangan rangka aman untuk menahan beban dinamis menggunakan baja ukuran 50 x 50 x 1,2 mm. Hal ini karena material ASTM A36 dan ASTM A500 untuk ukuran 50 x 50 x 1,2 mm memiliki faktor kemanan berturut-turut 2,162 dan 2,724. The flight control movement simulation tool is a visual aid to show the working mechanism of an airplane wing and tail close to reality. This tool aims as a learning method for aspiring pilots before driving an airplane. The study aims to design and analyze a flight control movement simulation frame using the finite element method. Static analysis was performed using SolidWorks 2017 software. The frame material used was ASTM A36 and ASTM 500 steel (square hollow section) with sizes of 50 x 50 x 1.2 mm and 40 x 40 x 1 mm. The load used is 375.25 kg, which is the weight of the aircraft's wing and tail. The analysis results show that a safe frame design to withstand dynamic loads uses 50 x 50 x 1.2 mm steel. The ASTM A36 and ASTM A500 materials for sizes 50 x 50 x 1.2 mm have a safety factor of 2.162 and 2.724, respectively.

Electrodynamic Treatment of Structural Elements Made of Aluminium and Magnesium Alloys

The article discusses the electrodynamic treatment (EDT) of thin-walled welded structures and EDT equipment, presents results of mathematical modelling concerning the effect of EDT on stresses in welded sheets made of aluminium alloy AMg6 as well as discusses the effect of EDT on the plastic strain mechanism. In addition, the article presents tests results concerning the effect of EDT during the welding of ship structures made of AMg6 plates and discusses the role of EDT in bulge formation. In addition, the article discusses the application of EDT during the repair welding of aero-engine nacelles made of magnesium alloy ML10 and the effect of EDT on openings in an airplane wing stinger in relation to its service life.

Flexible Carbon Nanotube/Polydimethylsiloxane Composite for the De-Icing of Airplane Wings

In the aviation industry, the process of de-icing is critical for stable flying because of the occurrence of airplane icing. To solve the icing problem, an electrical heating system is applied for airplane de-icing. Among the materials used in the electrical heating system, carbon-nanotube polymer composites are appropriate for an ice-prevention system owing to their rapid heating properties and flexibility. In this study, we fabricated a flexible carbon-nanotube/polydimethylsiloxane composite with a high content of carbon nanotube (20 wt%) for airplane de-icing. The high-load carbon nanotube composite was fabricated using a three-roll milling method, resulting in uniform dispersion of carbon nanotubes in the polymer matrix. The carbon nanotube/polydimethylsiloxane composites exhibited uniform and stable heating performance (from room temperature to 100 °C for 25 s without thermal aggregation). In addition, the carbon nanotube/polydimethylsiloxane composite is suitable for application to the curved surface of airfoils. For the de-icing experiments, a small airplane wing consisting of carbon nanotube/polydimethylsiloxane composite as a heating unit was fabricated with a scale ratio of 15:1. We conducted electrical heating and de-icing experiments using the developed airplane-wing system for actual anti-icing/de-icing applications.

The lifting force of an airplane wing when flying horizontally at high speeds. Explanation of the vortex trail.

In this paper, an explanation is given of the lift force of an airplane during horizontal flight. It is shown that during a flight, five vertical forces act on the airplane: gravity; pressure gradient with a minus sign; Archimedes force; potential force and the vortex force obtained from the action minimum. The first three forces were known before. The potential force was also known from the Bernoulli equation, but its effect on the airfoil from the air had not previously been taken into account. The vortex force obtained from the minimum action in the application to a continuous medium was not taken into account in aerodynamics. In horizontal flight the vortex force is directed upwards, it compensates for the gravity of the airplane at high speed commensurate with the speed of sound. The paper provides an explanation of the vortex trail behind the airplane, mentioned in the Millennium problem Navier-Stokes equation.

PROPERTIES OF A CERTAIN LOADED INTEGRAL OPERATOR WITH WEIGHT

In this paper, we consider a certain integral operator with a weight, loaded with operator term. It acts in the space of continuous functions. The conditions under which this operator is limited are determined, the form of its semigroup is es-tablished. The Cauchy problem for an integro-differential equation is considered as an application. Such equations arise in the theory of elasticity and models of biological processes: Proctor's problem on the equilibrium of an elastic beam, Volterra's problem on torsional vibrations, Prandtl's problem for calculating an airplane wing, in analysis of economic models, etc.