Aviation is the domain with one of the greatest technical developments. Thus the emergence and development at the consumer level of commercial UAVs has put the entire aerospace industry and national security system in front of a fulfilled fact. These unmanned human onboard systems and the continuous development of hardware and software systems are currently creating one of the biggest challenges: integration in airspace. The article reviews the risks, threats and concepts of illegal use of the drones.

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Renewable energy sources represent efficient and reliable energy solutions for the modern world, as they are eco-friendly alternatives to fossil fuels or nuclear power plants. The technologies available nowadays allow researchers to perform in-depth computational fluid dynamics analysis for systems that can generate green energy. The wind energy industry developed considerably as classic wind turbine models (horizontal axis wind turbines and vertical axis wind turbines) are constantly optimized and new configurations are studied in order to asses better performances. This paper presents the numerical investigation campaign of a reduced scale Lenz wind turbine model. The Lenz model has three blades that are attached directly on a vertical shaft. For the numerical simulations of the model, the ANSYS Fluent software is employed. For the evaluation of its self-starting behaviour the six degree of freedom method was employed and the configuration was studied for different moments of inertia. Furthermore, the chosen range of inlet velocities allowed the investigation of the influence of high Reynolds numbers on the proposed Lenz model and the vorticity magnitude contours were computed for different azimuth angles. Future work includes the validation of the numerical results with experimental data obtained during a wind tunnel testing campaign.

Due to the current technological evolution trend, the use of renewable energies seems to be the best suited solution for the environment protection against pollution. This paper aims to present the methodology used for the manufacturing and assembling processes of a drag based vertical axis wind turbine, the steps for both processes being addressed broadly. The manufactured vertical axis wind turbine can successfully function in wind conditions with speeds of up to 16m/s and manages to provide up to 5kW of power. The manufacturing materials used for the execution of the blades include metal sheets, mounted on a structural frame for better stiffness. The wind turbine rotor is comprised of three blades, that are installed on a shaft connected to a gear box which will transfer the torque to the permanent magnet generator. The whole process is described in the paper and the result consists of the installed turbine, that is ready to function in real environment operating conditions. The work carried out within this paper is relevant to the general know-how regarding wind turbine manufacturing and installation, as the authors highlight the main impediments they had to overcome when developing, executing and installing the described model.