Multidisciplinary analysis of a novel anti-icing system for a fixed wing UAV

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Special Issue on “Additive Manufacturing Technologies and Applications”

Additive Manufacturing (AM) is a well-known technology, first patented in 1984 by the French scientist Alain Le Mehaute [...

Development of a Computational Fluid Dynamics Model for Ice Formation: Validation and Parameter Analysis

: In the history of civil aircraft transportation, ice formation has been identified as a key factor in the safety of flight. Anti-icing and deicing systems have emerged through the years with the aim to prevent or to eliminate ice formation on wing airfoils, control surfaces and probes. Modern flying machines demand more efficiency in order to reduce the carbon footprint and increase the sustainability of flight transport. In order to achieve this goal, the need to have an efficient aircraft with an efficient and low power consuming system is fundamental. This paper proposes a new model for ice accretion using computational fluid dynamics (CFD). This model permits the simulation of the shape of the ice formed over a profile varying boundary condition (i.e., speed, liquid water content, and so on). The proposed model also takes into account the amount of heat transferred between the water and the surrounding environment and includes the effects of air turbulence on the ice formation process. The CFD simulations have been validated with NASA experimental outcome and show good agreement. The proposed model can be also used to investigate the effects of various parameters such as air speed, liquid water content, and air temperature on the ice formation process. The results evidence that the proposed model can accurately predict ice formation process and is suitable to optimize the design of anti-icing or deicing systems for aircraft and helicopters. This approach is not limited to aerospace but can also be exported to other applications such as transportation, wind turbine, energy management, and infrastructure

A multipurpose modular drone with adjustable arms produced via the FDM additive manufacturing process

AbstractThe present paper shows an innovative multirotor Unmanned Aerial Vehicle (UAV) which is able to easily and quickly change its configuration. In order to satisfy this feature, the principal structure is made of an universal plate, combined with a circular ring, to create a rail guide able to host the arms, in a variable number from 3 to 8, and the legs. The arms are adjustable and contain all the avionic and motor drivers to connect the main structure with each electric motor. The unique arm design, defined as all-in-one, allows classical single rotor configurations, double rotor configurations and amphibious configurations including inflatable elements positioned at the bottom of the arms. The proposed multi-rotor system is inexpensive because of the few universal pieces needed to compose the platform which allows the creation of a kit. This modular kit allows to have a modular drone with different configurations. Such configurations are distinguished among them for the number of arms, number of legs, number of rotors and motors, and landing capability. Another innovation feature is the introduction of the 3D printing technology to produce all the structural elements. In this manner, all the pieces are designed to be produced via the Fused Deposition Modelling (FDM) technology using desktop 3D printers. Therefore, an universal, dynamic and economic multi-rotor UAV has been developed

Additive Manufacturing Technologies and Applications

The present Special Issue proposes articles in the area of Additive Manufacturing with particular attention to the different employed technologies and the several possible applications. The main investigated technologies are the Selective Laser Sintering (SLS) and the Fused Deposition Modelling (FDM). These methodologies, combined with the Computer Aided Design (CAD), provide important advantages. Numerical, analytical and experimental knowledge and models are proposed to exploit the potential advantages given by 3D printing for the production of modern systems and structures in aerospace, mechanical, civil and biomedical engineering fields. The 11 selected papers propose different additive manufacturing methodologies and related applications and studies

Development of a multifunctional panel for aerospace use through SLM additive manufacturing

Lattice materials can overcome the need of light and stiff structures in the aerospace industry. The wing leading edge is one of the most critical parts for both on-board subsystem and structure features: it must withstand to the aerodynamic loads and bird-strike, integrating also the anti-ice system functions. Nowadays, this part is made by different components bonded together such as external skin, internal passageways, and feeding tubes. In the present work, a single-piece multifunctional panel made by additive manufacturing will be developed. Optimal design and manufacturing are discussed according to technological constraints, aeronautical performances and sustainability

a comparison between 3d printing and milling process for a spar cap fitting wing fuselage of uav aircraft

Abstract Topology optimization is playing an important role in the aircraft design. The demand of lower fuel consumption reflects on the optimization of the airframe of flying vehicles to reduce the structure weight, therefore improving the fraction of the payload. This work focuses on the replacement of an existing part (spar cap fitting) with the new topologically optimized part to be manufactured with 3D printing (Selective Laser Sintering -SLS). The manufacturing constraints (minimum dimension, growth orientation) influence on the optimal results is evaluated to compare traditional milling process' performance with the new SLS technique

A Mass Balance-Based Method for the Anaerobic Digestion of Rice Straw

Current rice straw disposal practices have serious repercussions on the environment and, in addition, do not consider its energy potential. On the contrary, the anaerobic digestion of rice straw makes it possible to produce renewable energy and to reintroduce into the soil the nutrients present in the digestate, at the same time, reducing greenhouse gas emissions from paddies. For rice straw of different geographical origin, by applying a mass balance method to the digester, the minimum requirements in terms of conditioners (nitrogen, phosphorus and potassium) and water, which allow obtaining the maximum production of methane, were calculated. The results obtained show that after the first 30 days (hydraulic retention time) for each ton of rice straw digested, the daily water consumption varies considerably from one country to another, from a minimum value of 1.5 m3/d to a maximum of 4.3 m3/d. After the same time, the addition of nitrogen and phosphorus is only required for the optimal anaerobic digestion of Indian rice straw. The low presence of these elements in Indian straw requires an addition of 3 kg/d of urea and 1.5 kg/d of superphosphate to compensate for the lack of nitrogen and phosphorus, respectively. In all the examined cases, the concentration of potassium, even if higher than the optimal value, does not reach levels that can significantly affect the methane production

Rice Straw: A Waste with a Remarkable Green Energy Potential

With reference to the province of Novara in northwest Italy, this study aims to raise awareness about the environmental benefits that can derive from the use of alternative rice straw management practices to those currently in use, also highlighting how the use of these straws for energy purposes can be a valid alternative to the use of non-renewable resources. Using the LCA (Life Cycle Assessment) method, the two rice straw management practices currently in place (open field combustion and straw incorporation) were compared with an alternative strategy consisting in their collection and removal. The results show that removal of straw allows reducing the emissions of pollutants significantly: about one-hundredth of the PM (Particulate Matter) formation compared to the open-field burning and about one-tenth of the ozone depletion (CFCs, HCFCs, halons, etc.) compared to both the other two practices. Moreover, the LCA results show how the use of rice straw to produce energy as an alternative to conventional fuels helps to reduce the global warming potential of rice cultivatio