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Aidan Jungo, Mengmeng Zhang, Jan B. Vos and Arthur Rizzi
The purpose of this paper is to present the status of the on-going development of the new computerized environment for aircraft synthesis and integrated optimization methods…
Abstract
Purpose
The purpose of this paper is to present the status of the on-going development of the new computerized environment for aircraft synthesis and integrated optimization methods (CEASIOM) and to compare results of different aerodynamic tools. The concurrent design of aircraft is an extremely interdisciplinary activity incorporating simultaneous consideration of complex, tightly coupled systems, functions and requirements. The design task is to achieve an optimal integration of all components into an efficient, robust and reliable aircraft with high performance that can be manufactured with low technical and financial risks, and has an affordable life-cycle cost.
Design/methodology/approach
CEASIOM (www.ceasiom.com) is a framework that integrates discipline-specific tools like computer-aided design, mesh generation, computational fluid dynamics (CFD), stability and control analysis and structural analysis, all for the purpose of aircraft conceptual design.
Findings
A new CEASIOM version is under development within EU Project AGILE (www.agile-project.eu), by adopting the CPACS XML data-format for representation of all design data pertaining to the aircraft under development.
Research limitations/implications
Results obtained from different methods have been compared and analyzed. Some differences have been observed; however, they are mainly due to the different physical modelizations that are used by each of these methods.
Originality/value
This paper summarizes the current status of the development of the new CEASIOM software, in particular for the following modules: CPACS file visualizer and editor CPACSupdater (Matlab) Automatic unstructured (Euler) & hybrid (RANS) mesh generation by sumo Multi-fidelity CFD solvers: Digital Datcom (Empirical), Tornado (VLM), Edge-Euler & SU2-Euler, Edge-RANS & SU2-RANS Data fusion tool: aerodynamic coefficients fusion from variable fidelity CFD tools above to compile complete aero-table for flight analysis and simulation.
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Hoyon Hwang, Jaeyoung Cha and Jon Ahn
The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft…
Abstract
Purpose
The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft design framework provides a simple method to design solar aircraft for users of all levels of experience.
Design/methodology/approach
This design framework consists of algorithms and user interfaces for the design of experiments, optimization and mission analysis that includes aerodynamics, performance, solar energy, weight and flight distances.
Findings
The proposed sizing method produces the optimal solar aircraft that yields the minimum weight and satisfies the constraints such as the power balance, the night time energy balance and the lift coefficient limit.
Research limitations/implications
The design conditions for the sizing process are given in terms of mission altitudes, flight dates, flight latitudes/longitudes and design factors for the aircraft configuration.
Practical implications
The framework environment is light and easily accessible as it is implemented using open programs without the use of any expensive commercial tools or in-house programs. In addition, this study presents a sizing method for solar aircraft as traditional sizing methods fail to reflect their unique features.
Social implications
Solar aircraft can be used in place of a satellite and introduce many advantages. The solar aircraft is much cheaper than the conventional satellite, which costs approximately $200-300m. It operates at a closer altitude to the ground and allows for a better visual inspection. It also provides greater flexibility of missions and covers a wider range of applications.
Originality/value
This study presents the implementation of a function that yields optimized flight performance under the given mission conditions, such as climb, cruise and descent for a solar aircraft.
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José Pedro Soares Pinto Leite and Mark Voskuijl
In recent years, increased awareness on global warming effects led to a renewed interest in all kinds of green technologies. Among them, some attention has been devoted to…
Abstract
Purpose
In recent years, increased awareness on global warming effects led to a renewed interest in all kinds of green technologies. Among them, some attention has been devoted to hybrid-electric aircraft – aircraft where the propulsion system contains power systems driven by electricity and power systems driven by hydrocarbon-based fuel. Examples of these systems include electric motors and gas turbines, respectively. Despite the fact that several research groups have tried to design such aircraft, in a way, it can actually save fuel with respect to conventional designs, the results hardly approach the required fuel savings to justify a new design. One possible path to improve these designs is to optimize the onboard energy management, in other words, when to use fuel and when to use stored electricity during a mission. The purpose of this paper is to address the topic of energy management applied to hybrid-electric aircraft, including its relevance for the conceptual design of aircraft and present a practical example of optimal energy management.
Design/methodology/approach
To address this problem the dynamic programming (DP) method for optimal control problems was used and, together with an aircraft performance model, an optimal energy management was obtained for a given aircraft flying a given trajectory.
Findings
The results show how the energy onboard a hybrid fuel-battery aircraft can be optimally managed during the mission. The optimal results were compared with non-optimal result, and small differences were found. A large sensitivity of the results to the battery charging efficiency was also found.
Originality/value
The novelty of this work comes from the application of DP for energy management to a variable weight system which includes energy recovery via a propeller.
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Mariusz Szóstak, Tomasz Nowobilski, Abdul-Majeed Mahamadu and David Caparrós Pérez
Unmanned aerial vehicles (UAV), colloquially called drones, are widely applied in many sectors of the economy, including the construction industry. They are used for building…
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Purpose
Unmanned aerial vehicles (UAV), colloquially called drones, are widely applied in many sectors of the economy, including the construction industry. They are used for building inspections, damage assessment, land measurements, safety inspections, monitoring the progress of works, and others.
Design/methodology/approach
The study notes that UAV pose new, and not yet present, risks in the construction industry. New threats arise, among others, from the development of new technologies, as well as from the continuous automation and robotization of the construction industry. Education regarding the safe use of UAV and the proper use of drones has a chance to improve the safety of work when using these devices.
Findings
The procedure (protocol) was developed for the correct and safe preparation and planning of an unmanned aerial vehicle flight during construction operations.
Originality/value
Based on the analysis of available sources, no such complete procedure has yet been developed for the correct, i.e. compliant with applicable legal regulations and occupational health and safety issues, preparation for flying UAV. The verification and validation of the developed flight protocol was performed on a sample of over 100 different flight operations.
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Samuel Aryee, Tae-Yeol Kim, Qin Zhou and Seongmin Ryu
This paper aims to examine how team-level empowering leadership related to service performance through thriving at work and how shared organizational social exchange and customer…
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Purpose
This paper aims to examine how team-level empowering leadership related to service performance through thriving at work and how shared organizational social exchange and customer orientation moderated the latter relationships.
Design/methodology/approach
The authors collected the data from 283 flight attendants and their supervisors working at a major Korean airline. Multi-level analyses were used to test the effect of empowering leadership on employee outcomes.
Findings
Both team-level empowering leadership and customer orientation were significantly and indirectly associated with service performance via thriving at work. Additionally, customer orientation significantly moderated the relationship between team-level empowering leadership and thriving at work such that the relationship was stronger when customer orientation was low rather than high. In addition, shared organizational social exchange augmented the influence of team-level empowering leadership on service performance but not on thriving at work.
Practical implications
The findings suggest that team-level empowering leadership is more effective in enhancing thriving at work of employees when their customer orientation is low rather than high. In addition, a shared high-quality organizational social exchange augments the effect of empowering leadership on employees’ service performance.
Originality/value
This paper provides initial evidence of the interaction of team-level empowering leadership and individual¬-level customer orientation on thriving at work and service performance. Additionally, it documents the differential augmenting effect of shared organizational social exchange on the relationship between empowering leadership and these outcomes. Collectively, the findings explain why and when team-level empowering leadership relates to service performance.
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