Supersonic business jet conceptual design in a multidisciplinary design analysis optimization environment

This paper introduces a multidisciplinary design analysis and optimization (MDAO) environment called GENUS, which has been developing in Cranfield University’s Aircraft Design Group. The GENUS aircraft design environment has the feature of modular, expandable, flexible, independent, sustainable, and performable. This paper discusses the application of this environment to supersonic business jets (SSBJs), which are regarded as the pioneer of the next generation of supersonic airliners. Methodologies appropriate to SSBJ are developed in the GENUS environment. Mach plane cross-sectional area is calculated based on the parametric geometry model. PANAIR is modified to do automated aerodynamic analysis. Drag coefficient is corrected by Harris wave drag calculation and form factor method. NASA EngineSim is integrated for engine modeling. Carlson simplified sonic boom prediction method has been used for sonic boom signature prediction. Results of the Cranfield E5 SSBJ are presented. Low-boom and low-drag SSBJ designs can be explored based on the framework

Conceptual design methodology for blended wing body aircraft

The desire to create an environmentally friendly aircraft that is aerodynamically efficient and capable of conveying large number of passengers over long ranges at reduced direct operating cost led aircraft designers to develop the Blended Wing Body(BWB) aircraft concept. The BWB aircraft represents a paradigm shift in the design of aircraft. The design offers immense aerodynamics and environmental benefits and is suitable for the integration of advanced systems and concepts like laminar flow technology, jet flaps and distributed propulsion. However, despite these benefits, the BWB is yet to be developed for commercial air transport. This is due to several challenges resulting from the highly integrated nature of the configuration and the attendant disciplinary couplings. This study describes the development of a physics based, deterministic, multivariate design synthesis optimisation for the conceptual design and exploration of the design space of a BWB aircraft. The tool integrates a physics based Athena Vortex Lattice aerodynamic analysis tool with deterministic geometry sizing and mass breakdown models to permit a realistic conceptual design synthesis and enables the exploration of the design space of this novel class of aircraft. The developed tool was eventually applied to the conceptual design synthesis and sensitivity analysis of BWB aircraft to demonstrate its capability, flexibility and potential applications. The results obtained conforms to the pattern established from a Cranfield University study on the BlendedWing Body Aircraft and could thus be applied in conceptual design with a reasonable level of confidence in its accuracy

Generic bill of functions, materials, and operations for SAP2 configuration

International audienceMost available studies on configuration focus on either sales configuration specifying functional features or production configuration addressing product components. It has been well recognised that automating most of the activities associated with specification, engineering, and process planning of customised products and their interactions is one key in achieving product customisation. Thus, treating sales configuration and product configuration separately may not contribute to product customisation from a systematic view although they may lead to the improvement of individual stages. Recognising this limitation of existing studies, in this paper, we propose integrated SAles, Product and Production (SAP2) configuration, which helps achieve product customisation from a holistic view. Its rationale lies in automating consistently sales, product and production configuration activities in one system. In view of the importance of configuration models, we focus on the model underpinning SAP2 configuration called generic bill of functions, materials and operations (GBoFMO) and discuss it in detail. As the core of SAP2 configuration, GBoFMO can provide companies with an insight into organising the large volumes of data and knowledge in the life cycle of product family development. We also report a case study of light passenger aircrafts to illustrate the GBoFMO

A set-based approach to passenger aircraft family design

In today's highly competitive civil aviation market, aircraft manufacturers develop aircraft families in order to satisfy a wide range of requirements from multiple airlines, with reduced costs of ownership and shorter lead time. Traditional methods for designing passenger aircraft families employ a sequential, optimisation-based approach, where a single configuration and systems architecture is selected fairly early which is then iteratively analysed and modified until all the requirements are met. The problem with such an approach is the tendency of the optimisers to exploit assumptions already 'hard-wired' in the computational models. Subsequently the design is driven towards a solution which, while promising to the optimiser, may be infeasible due to the factors not considered by the models, e.g. integration and installation of promising novel technological solutions, which result in costly design rework later in the design process. Within this context, the aim is to develop a methodology for designing passenger aircraft families, which provides an environment for designers to interactively explore wider design space and foster innovation. To achieve this aim, a novel methodology for passenger aircraft family design is proposed where multiple aircraft family solutions are synthesised from the outset by integrating major components sets and systems architectures set. This is facilitated by integrating set theory principles and model-based design exploration methods. As more design knowledge is gained through analysis, the set of aircraft family solutions is gradually narrowed-down by discarding infeasible and inferior solutions. This is achieved through constraint analysis using iso-contours. The evaluation has been carried out through an application case-study (of a three-member passenger aircraft family design) which was executed with both the proposed methodology and the traditional approach for comparison. The proposed methodology and the case-study (along with the comparison results) were presented to a panel of industrial experts who were asked to comment on the merits and potential challenges of the proposed methodology. The conclusion is that the proposed methodology is expected to reduce the number of costly design changes, enabling designers to consider novel systems technologies and gain knowledge through interactive design space exploration. It was pointed out, however, that while the computational enablers behind the proposed approach are reaching a stage of maturity, allowing a multitude of concepts to be analysed rapidly and simultaneously, this still is expected to present a challenge from organisational process and resource point of view. It was agreed that by considering a set of aircraft family solutions, the proposed approach would enable the designers to delay critical decisions until more knowledge is available, which helps to mitigate risks associated with innovative systems architectures and technologies

Air Transportation 2050 - A Holistic View

The lecture introduces into the view of holistic aerospace technology research. Starting at global aviation developments various research results on operational laminar technology imapct and climate optimized aircraft design are presente

Low-boom low-drag optimization in a multidisciplinary design analysis optimization environment

This paper introduces a multidisciplinary design analysis and optimization environment called GENUS. The GENUS aircraft design environment’s key features are that it is modular, expandable, flexible, independent, and sustainable. This paper discusses the application of this environment to the design of supersonic business jets (SSBJs). SSBJs are regarded as the pioneers of the next generation of supersonic airliners. Methodologies appropriate to SSBJs are developed in the GENUS environment. The Mach plane cross-sectional area is calculated based on the parametric geometry model. PANAIR is integrated to perform automated aerodynamic analysis. The drag coefficient is corrected by the Harris wave drag calculation and form factor method. The sonic boom intensity is predicted by the wave form parameter method, which is validated by PCBoom. The Cranfield E-5 SSBJ is chosen as a baseline configuration. Low-boom and low-drag optimization are carried out based on this configuration. Through the optimization, the sonic boom intensity is mitigated by 71.36% and the drag decreases by 20.65%

Influences on aircraft target off-block time prediction accuracy

With Airport Collaborative Decision Making (A-CDM) as a generic concept of working together of all airport partners, the main aim of this research project was to increase the understanding of the Influences on the Target Off-Block Time (TOBT) Prediction Accuracy during A-CDM. Predicting the TOBT accurately is important, because all airport partners use it as a reference time for the departure of the flights after the aircraft turn-round. Understanding such influencing factors is therefore not only required for finding measures to counteract inaccurate TOBT predictions, but also for establishing a more efficient A-CDM turn-round process. The research method chosen comprises a number of steps. Firstly, within the framework of a Cognitive Work Analysis, the sub-processes as well as the information requirements during turn-round were analysed. Secondly, a survey approach aimed at finding and describing situations during turn-round that are critical for TOBT adherence was pursued. The problems identified here were then investigated in field observations at different airlines’ operation control rooms. Based on the findings from these previous steps, small-scale human-in-the-loop experiments were designed aimed at testing hypotheses about data/information availability that influence TOBT predictability. A turn-round monitoring tool was developed for the experiments. As a result of this project, the critical chain of turn-round events and the decisions necessary during all stages of the turn-round were identified. It was concluded that information required but not shared among participants can result in TOBT inaccuracy swings. In addition, TOBT predictability was shown to depend on the location of the TOBT turn-round controller who assigns the TOBT: More reliable TOBT predictions were observed when the turn-round controller was physically present at the aircraft. During the experiments, TOBT prediction could be improved by eight minutes, if available information was cooperatively shared ten minutes prior turn-round start between air crews and turn-round controller; TOBT prediction could be improved by 15 minutes, if additional information was provided by ramp agents five minutes after turnround start

Comparative analysis of new configurations of aircraft aimed at competitiveness, environmental compatibility and safety

This Ph.D. Thesis aims at suggesting a proper integrated and multidisciplinary design methodology to improve the current conceptual and preliminary design phases of breakthrough innovative aerospace products. The methodology, based on a Systems Engineering approach, is presented together with an envisaged toolchain, consisting of both commercial and ad-hoc developed software, integrated in a Model-Based Systems Engineering perspective. In addition, for the sake of clarity and for validation purposes, a specific case study has been selected and developed all along the document. The reference case-study is inspired to a real pre-feasibility study in which the research group of Politecnico di Torino, which the author of this Thesis belongs to, has been involved. The project aims at developing a suborbital vehicle able to perform parabolic flights for both scientific and touristic purposes. This kind of initiatives paves the way for the future hypersonic vehicles, because it allows to crucial enabling technologies to be tested and validated in relevant environment but with lower performances’ requirements. The Thesis is articulated in seven Chapters with an introduction and conclusion sections and in each Chapter a balanced mix between theoretical investigation, mathematical model development, tool selection or development and application to the selected case study is guaranteed. This document starts reporting the major reasons why an innovative design methodology should be envisaged to deal with the increasing level of complexity in the aerospace domain. In particular, in the first Chapter, a brief overview of existing or underdevelopment initiatives related to hypersonic is reported, together with the description of the different types of mission in which the new hypersonic vehicles will be exploited. Moreover, the major issues related to the infrastructures required to operate these transportation systems are summarized. As far as operations are concerned, a short section makes the readers aware of the current under-development regulatory framework. Then, the integrated multidisciplinary design methodology is presented starting from the very high level analyses up to the sizing of the different components of the transportation system. All along the document, crucial role is played by requirements, whose management can allow a complete traceability of the different design characteristics during the overall product life-cycle. Furthermore, proper algorithms allowing to move from purely qualitative to quantitative trade-offs, are presented, with a noticeable advantage in terms of traceability and reproducibility. Eventually, further improvements of both the tool-chain and the reference case studies are envisaged for future developments