Development Of Unmanned Air Vehicles Research Articles

Micro gas turbine combustion chamber CFD modelling

The interest in micro gas turbines has been steadily increasing. As a result, the researchers’ attention has been focused on obtaining optimal configurations for micro gas turbines depending on the applications in which they are used. Micro gas turbines are suitable for both civil and military applications. Presently, they are often used in the development of Unmanned Air Vehicles (UAVs). Micro gas turbines have the following advantages: a wider range of options regarding the used fuel and a significant system weight reduction. This paper presents the CFD modelling results regarding an annular type combustion chamber. This combustion chamber is part of a 80 daN micro gas turbine, destined to equip a small scale multifunctional airplane. The combustion chamber is equipped with eight pressure-swirl injectors, using Jet-A as fuel. A 3D RANS numerical integration of the Navier-Stokes equations has been carried out, using an Eddy Dissipation combustion Model (EDM) and the k-ε turbulence model, implemented in a numerical simulation conducted using the commercial software ANSYS CFX. An unstructured computational grid, generated using ICEM CFD, has been used. The fuel is injected directly in the fire tube in the form of droplets. The initial fuel droplet’s diameter has been considered to be 50µm and the fuel spraying cone angle has been set at 90°. The fuel droplet break-up and evaporation processes have been simulated using numerical models available in ANSYS CFX library. A two steps reaction mechanism, which takes into consideration the formation of NO, has been used. The results thus obtained are encouraging. The flame developed in the central area of the fire tube, its walls thus not being subjected to high temperatures. Also, the maximum temperatures were obtained in the primary zone of the fire tube. The temperature then decreased in the fire tube’s secondary zone and dilution zone, until it reached an average value of 1200 K at the combustion chamber exit. Regarding the pressure, based on the numerical simulation results, a 5% pressure loss has been obtained. The numerical results will be validated by conducting combustion tests on a testing rig which will be developed inside the institute’s Combustion Chamber Laboratory.

SAN: an Integrated Unmanned Air Vehicles Interdictor System Concept

The development of unmanned air vehicles (UAVs) has been very rapid recently. The wide accessibility of UAVs has unlocked a great potential for the malicious or accidental damage or destruction of property or other aircraft in flight. UAVs can be used for espionage, contraband, and the trafficking or transport of arms and hazardous materials. Every month sees a growing number of reports of incidents that involve remote-controlled UAVs operated for aerial video recording. These incidents justify undertaking research into minimizing the hazards which UAVs may potentially cause. A concept was developed for a solution dedicated to this problem and comprising an integrated modular anti-UAV system for application in commercial (civilian) markets in the areas of security of mass events, strategic enterprises, and critical strategic infrastructure in Poland. The proposed system is intended to incapacitate any UAVs that breach a predefined air space and bring the incapacitated UAVs safely to the ground. The project is developed jointly by the Institute of Armament Technology at the Military University of Technology (Warsaw, Poland) and Polish company Ellipsis Sp. z o.o.

Unmanned Air Vehicle and Simulation .

A general account of unmanned air vehicles (UAVs) is given and their various roles, both lethal and non-lethal ones, are discussed. Elements of an UAV system used for reconnaissance, surveillance and target designation have been described to highlight the role of simulation in acquisition, design, development, testing, evaluation, and operation of such a system. Various applications of simulation studies for UAVs are mentioned. An attempt has been made to highlight how simulation helps in identifying design deficiencies and thus improve the design through the following three typical problems encountered during design and development of UAVs at the Aeronautical Development establishment:(i) launch dynamics of Lakshya, (ii) tow system dynamics, Lakshya tow body, and (iii) hardware in-line simulation -way point navigation-Nishant.