An evolutionary, agent-assisted strategy for conceptual design space decomposition

Author(s):  
I. C. Parmee ◽  
M. A. Beck
Aerospace ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 54
Author(s):  
Julia A. Cole ◽  
Lauren Rajauski ◽  
Andrew Loughran ◽  
Alexander Karpowicz ◽  
Stefanie Salinger

There is currently interest in the design of small electric vertical take-off and landing aircraft to alleviate ground traffic and congestion in major urban areas. To support progress in this area, a conceptual design method for single-main-rotor and lift-augmented compound electric helicopters has been developed. The design method was used to investigate the feasible design space for electric helicopters based on varying mission profiles and technology assumptions. Within the feasible design space, it was found that a crossover boundary exists as a function of cruise distance and hover time where the most efficient configuration changes from a single-main-rotor helicopter to a lift-augmented compound helicopter. In general, for longer cruise distances and shorter hover times, the lift-augmented compound helicopter is the more efficient configuration. An additional study was conducted to investigate the potential benefits of decoupling the main rotor from the tail rotor. This study showed that decoupling the main rotor and tail rotor has the potential to reduce the total mission energy required in all cases, allowing for increases in mission distances and hover times on the order of 5% for a given battery size.


Author(s):  
Xin Zhao ◽  
Smruti Sahoo ◽  
Konstantinos Kyprianidis ◽  
Sharmila Sumsurooah ◽  
Giorgio Valente ◽  
...  

Abstract To achieve the goals of substantial improvements in efficiency and emissions set by Flightpath 2050, fundamentally different concepts are required. As one of the most promising solutions, electrification of the aircraft primary propulsion is currently a prime focus of research and development. Unconventional propulsion sub-systems, mainly the electrical power system, associated thermal management system and transmission system, provide a variety of options for integration in the existing propulsion systems. Different combinations of the gas turbine and the unconventional propulsion sub-systems introduce different configurations and operation control strategies. The trade-off between the use of the two energy sources, jet fuel and electrical energy, is primarily a result of the trade-offs between efficiencies and sizing characteristics of these sub-systems. The aircraft structure and performance are the final carrier of these trade-offs. Hence, full design space exploration of various hybrid derivatives requires global investigation of the entire aircraft considering these key propulsion sub-systems and the aircraft structure and performance, as well as their interactions. This paper presents a recent contribution of the development for a physics-based simulation and optimization platform for hybrid electric aircraft conceptual design. Modeling of each subsystem and the aircraft structure are described as well as the aircraft performance modeling and integration technique. With a focus on the key propulsion sub-systems, aircraft structure and performance that interfaces with existing conceptual design frameworks, this platform aims at full design space exploration of various hybrid concepts at a low TRL level.


2021 ◽  
Author(s):  
Saptarshi Datta

A parametric, concurrent design methodology for manufacturing of metallic and composite structures is established. Often, during a new product development, designs prepared using the “Sequential” or “Waterfall” approach are rejected or require significant rework during manufacturing, as designers are not always versed with manufacturing principles. Similarly, manufacturers are not always versed in design principles resulting in designs that do not cater to the functional requirements. The goal of this study is to establish a methodology right from the scope to the detailed design for developing manufacturable structures using the “Concurrent Engineering” approach. Existing literature on “Design Optimization for Manufacturing” predominantly focus on single variable optimization problems geared towards conceptual designs. The designs developed through such optimization cater towards functional performance within a “Fixed Design Space” while not accounting for manufacturing or operational challenges. The methodology developed in this study enables “Design for Manufacturing” for “Detailed Designs” through selection of a conceptual design and subsequently optimizing the selected conceptual design for a set of functional parameters. An “Integrated Product Development” approach is used, whereby, the functional requirements are linked to both design and manufacturing variables and optimization is conducted in an “Augmented Design Space” which is not available when only considering design or manufacturing variables. Three case studies involving both “Conceptual” and “Detailed” designs have been used to illustrate the methodology presented. Case I documents the design of a Flight Control System Bracket. Case II illustrates the use of “2D” composite structures to fabricate a roll frame. Case III involves the development of a “3D” composite door for a light unpressurized aircraft. For each of the three case studies a separate development approach has been employed. Case I uses an analytical approach, Case II uses FEM while CASE III employs a hybrid approach comprising of both FEM and analytical techniques.


2021 ◽  
Author(s):  
Abhishek Dutta

Abstract This paper introduces the methodology of systematic robust design of a multirotor vehicle as an example of how to carry out the robust design of a physical system. Robustness in aerial vehicles is highly desirable as it guarantees a desired level of performance even under environmental uncertainties. Thus far, robustness has been considered in terms of active control in the space of multirotor vehicles, but exploration of the design space itself is lacking. In this work, a conceptual design followed by a robust design is performed to come up with the specifications that lead to least uncertain performance of the multirotor vehicle with respect to stochastic wind disturbances.


Author(s):  
William H. Wood

Abstract Formal methods for conceptual design must embrace the uncertainty that pervades the earliest parts of the design process. Operating over this uncertainty, decision-based design measures the value of restricting the design space as well as the impact of refining design evaluation or analysis models. Missing from this framework is the cost in terms of design freedom of restricting the design space. We propose a measure of design freedom based on probabilistic entropy and demonstrate its application to two example conceptual design problems.


Author(s):  
Dietmar Göhlich ◽  
Tu-Anh Fay ◽  
Sangyoung Park

AbstractMany cities have announced ambitious plans to introduce zero-emission electric bus systems. The transformation process to electric bus systems opens up a vast design space as different charging strategies, charging technologies and battery types are available. Therefore, a profound assessment strategy is necessary to find a “most suitable system solution” under given strategic and operational requirements.In this study, we present a new methodology for conceptual design of urban electric bus systems. First, the available e-bus technologies are analysed with a special focus on charging systems, battery technology and aging. Relational functional analysis is used to derive a suitable simulation model. Based on the operational requirements, an energetic simulation of the e-bus is carried out, and the required battery capacity is obtained. Subsequently, the design space is reduced by applying a qualitative cost- technology compatibility matrix taking cost and battery aging into account. The applicability of the model is shown for an exemplary realistic operational scenario to identify three most expedient concepts, which are finally validated with an in-depth analysis.


Sign in / Sign up

Export Citation Format

Share Document