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Year 2024 Volume 05 Issue 01
Urban Air Mobility (UAM) Network. Case Study: Baku Metropolitan Area
Tarih: 21-06-2024 | Yazar(lar): Tapdig Imanov
Abstract (Özet)
The development and implementation of the Urban Air Mobility transportation system, using an electric vertical takeoff and landing (e-VTOL) aircrafts are the most promising solution to mitigate growing congestion in big cities. The multiple studies and assumed forecasts indicate transformation of urban and regional transportation infrastructure while applying the air mobility concept. This study analyses the feasibility of UAM operation focused on selection of service segmentation with relevant use cases, which allow to define suitable air vehicle configuration for optimization of possible air network development for Baku city and suburban areas. The result of the study introduces air vehicle features including flight range, payload ratio, as well as several weather condition aspects for safe operations and outlines approaches to define suitable regulatory framework requirements for public departments. The findings provide a practical perspective for urban planners and involved single companies, which may be useful guidelines at initial stages of UAM services and obtaining significant information about e-VTOL aircrafts and its design configurations to overcome arising barriers in the implementation processes.
The Innovation in Air Plasma Spray for Hardfacing
Tarih: 21-06-2024 | Yazar(lar): Duong Vu
Abstract (Özet)
Thermal spray coating plays a significant role in industry. The wear-resistant deposition helps to provide a longer life cycle for the components. There is a small amount of effort going into developing a coating that improves the coefficient of friction. Compared with other deposition techniques, plasma spray coating can be recommended for a wide range of substrate materials to produce a stable, wear-resistant material. The plasma-sprayed deposition not only improves tribological performance but also embeds the desired mechanical and physical properties. In plasma spray technology, the inert gas used is mostly plasma jet. To create the wear-resistant coatings, the engineers apply self-flux or ceramic powder, but these materials are expensive. Some positive results of deposition using the amorphous powder encouraged the engineers and researchers. But a few of the investigations on the air plasma spray using Fe-based powder used ordinary air as a potential substitution to save on production costs. The aim of this work is the study of Fe-based sparing involving the modification of a plasma torch, for which hardfacing provides the wear resistance.
Navigating the Work Passion and Safety Behavior Examining the Role of Safety Locus of Control in the Aviation Sector
Tarih: 21-06-2024 | Yazar(lar): İnan Eryılmaz, Tugay Öney, Yeşim Tüm Kılıç, Tuğba Erhan
Abstract (Özet)
The human factor with inimitable qualifications is critical in providing safety by highlighting the keyword harmony to define the interaction between humans and technology in the aviation sector. In this role, it is vital to determine the intense emotions and motivations that can facilitate and support aviation sector employees in stabilizing the perceived safety behavior when confronting and coping with heavy workloads and stress. Thus, the current research aims to investigate the impact of work passion on the safety behavior of aviation sector employees and scrutinize the mediatory role of safety locus of control in the relationship between these two variables. By this aim, 541 participants working in different departments in the aviation sector are reached out. Confirmatory factor analysis, correlation analysis, multiple regression analysis, and Medmod module of Jamovi for mediation analyses were carried out to assess the model and hypotheses of the research. Drawing from the research results, it has been concluded that harmonious passion positively predicts safety behavior. In contrast, obsessive passion does not affect safety behavior. Besides, it has been observed that the internal locus of control has a full mediating role in the relationship between harmonious passion, obsessive passion, and safety behavior. On the contrary, it was revealed that external locus of control does not serve as a mediator in the link between harmonious passion, obsessive passion, and safety behavior. Research findings are discussed, drawn from theoretical support, and recommendations are presented regarding the sector and future research.
NUMERICAL AERODYNAMIC AND AEROACOUSTIC ANALYSIS OF TOROIDAL PROPELLER DESIGNS
Tarih: 21-06-2024 | Yazar(lar): Xuan-duc Vu, Anh-tuan Nguyen, Tuong-linh Nha, Quan Chu, Cong-truong Dınh
Abstract (Özet)
Drones have a major drawback which prevents them from being used extensively - the excessive noise they produce. This article presents an optimization process of aerodynamic noise reduction for a novel design called the Toroidal Propeller, which consists of two blades looping together so that the tip of one blade curves back into the other, has been designed by the Aerospace Propulsion Systems (APSs) research team at School of Mechanical Engineering, Hanoi University of Science and Technology. In addition, four toroidal propellers with different curved shapes (pitch) and Number of Blades (NOB) are considered. The objective of this research is to investigate the effects of modifying the geometry design of the Toroidal Propeller on the intensity of blade tip vortex and aerodynamic flow characteristics passing through the blade. The ultimate goal is to decrease blade tip vortex and turbulence produced by the blade, which can help estimate the sound pressure level and minimize it without causing significant performance losses. Based on the outcome results, the models of the four geometry studies are compared in terms of Acoustic Power Level (APL), Surface Acoustic Power Level (SAPL), Thrust, Torque, and Power. In general, the propeller model with NOB of 3 provides the most optimal efficiency in terms of both Thrust and APL. At the output cross-section, the APL dropped from nearly 139 dB to 121 dB, while the Thrust increased from almost 6.2N to 8.7N compared to the first version of the Toroidal Propeller model.
Design and Simulation of Seats for Emergency Landing Conditions in Electrical VTOLs
Tarih: 21-06-2024 | Yazar(lar): Hasan Totoş, Çağlar Üçler
Abstract (Özet)
Emerging electrification technologies in aviation and recent advances drive the increased usage of electrical vertical take-off and landing (VTOL) air vehicles. Weight considerations are predominant due to the weaker powertrain and lower payload capacity. Moreover, most systems are automated, and there is no distinction between pilot and passenger seats anymore. Conventional aircraft seating typically exhibits excessive weight, necessitating the development of lightweight troop seats with simple designs and textile seat pans and backrests. This research focuses primarily on the design aspects of these lightweight troop seats. There are already guiding military standards and civilian codes for physical tests for passenger or pilot seats. Nevertheless, there needs to be a comprehensive document combining all of these and explaining how simulation tools can be practically used for the same purpose. Consequently, a generic design was generated based on the troop seat of military helicopters, which was then tested and simulated virtually by finite element analysis according to MIL-S-85510, CS27, and CS29 standards. After finalizing the static tests for forward, rearward, lateral, downward, and upward g forces on a 10-degree floor deformation in the longitudinal axis, implicit dynamic tests were conducted with loading in longitudinal and vertical directions as specified by the MIL-S-85510 standards. Then, hotspot analysis is made for stress interpretation. As a result, a near-optimum design was achieved with stresses 10% lower than the yield stress of the materials, which can be used on board an electrical VTOL.