Marco Fioriti

Collaborative System of Systems Multidisciplinary Design Optimization for Civil Aircraft: AGILE EU project

As part of H2020 EU project AGILE, A Collaborative System of Systems Multidisciplinary Design Optimization research approach is presented in this paper. This approach relies on physics-based analysis to evaluate the correlations between the airframe design, as well as propulsion, aircraft systems, aerodynamics, structures and emission, from the early design process, and to exploit the synergies within a simultaneous optimization process. Further, the disciplinary analysis modules from multiple organizations, involved in the optimization are integrated within a distributed framework. The disciplinary analysis tools are not shared, but only the data are distributed among partners through a secured network of framework. In order to enable and to accelerate the deployment of collaborative, large scale design and optimization frameworks, the AGILE Paradigm, a novel methodology, has been formulated during the project. The main elements composing the AGILE Paradigm are the Knowledge Architecture (KA), and the Collaborative Architecture (CA). The first formalizes the overall product development process in a multi-level structure. The latter formalizes the collaborative process within the entire supply chain, and defines how the multiple stakeholders interact with each other.The current paper is focused on the application of using the AGILE Paradigm to solve system of stystems MDO on a regional jet transport aircraft. The focus of the current research paper is: 1) Creation of a system of systems frame work using AGILE Paradigm to support multidisciplinary distributive analysis capability. The framework involves physics based modules such as : Airframe synthesis, aerodynamics, structures, aircraft systems , propulsion system design, nacelle design, nacelle airframe integration, aircraft mission simulation,costs and emissions. 2) Validate the frame work with case study of a regional jet reference aircraft. 3) Assess the sensitivity and coupling of design parameters, local disciplinary optimizataion and its effect on global optimization objectives or constraints. The effects of varying Bypass Ratio (BPR) of engine, offtake effects due to degree of electrification and nacelle effects are propagated through the AGILE MDO framework and presented.

Automated Selection of the Optimal On-board Systems Architecture within MDO Collaborative Environment

The on-board systems are having even more importance in aircraft design since the continuous research for a competitive, more optimized and less costly aircraft. In addition, the introduction of new technologies related to the More Electric Aircraft and All Electric Aircraft concepts have raised the interest on on-board systems discipline giving the option of analyzing different architectures. The present paper would enhance the selection of the best on-board systems architecture introducing a new workflow, which is able to identify the best architecture in terms of procurement and operating cost. Since the importance of fuel required providing the secondary power, the effect of each specific architecture on engine performance is particularly considered including a detailed engine module. The workflow is implemented in Optimus framework within a collaborative and multidisciplinary environment and it is open to be integrated with additional modules increasing the fidelity of the analysis. To explore the capability of the defined workflow, the H2020 AGILE regional jet is identified as test case.

Assessment of airframe-subsystems synergy on overall aircraft performance in a Collaborative Design

A Collaborative and Distributed Multidisciplinary Design Optimization (MDO) methodology is presented, which uses physics based analysis to evaluate the correlations between the airframe design and its sub-systems integration from the early design process, and to exploit the synergies within a simultaneous optimization process. Further, the disciplinary analysis modules involved in the optimization task are located in different organization. Hence, the Airframe and Subsystem design tools are integrated within a distributed overall aircraft synthesis process. The collaborative design process is implemented by making use of DLRs engineering framework RCE. XML based central data format CPACS is the basis of communication to exchange model information between the analysis modules and between the partner organizations involved in the research activity. As a use case to evaluate the presented collaborative design method, an unmanned Medium Altitude Long Endurance (MALE) configuration is selected. More electric sub-systems combinations based on the mission requirements are considered. The deployed framework simultaneously optimizes the airframe along with the sub-systems. DLRs preliminary aircraft design environment is used for the airframe synthesis, and the Sub-systems design is performed by the ASTRID tool developed by Politecnico di Torino. The resulting aircraft and systems characteristics are used to assess the mission performance and optimization. In order to evaluate the physics based framework and system-airframe synergies, three case studies are considered: a) Subsystem Architectures effect on overall aircraft performance for a given mission and fixed airframe. b) Effects of variation of mission scenario on aircraft performance for a chosen subsystem architecture and fixed airframe. c) Optimization involving wing planform variables and subsystem architecture for a given mission.

On-Board Systems Preliminary Sizing in an Overall Aircraft Design Environment

An innovative aircraft preliminary design environment is presented, in particular highlighting the impacts of on-board systems design discipline on the Overall Aircraft Design, especially in terms of mass changes and fuel consumptions. The design environment has been conceived and set up during a collaboration between Politecnico di Torino and the German Aerospace Center (DLR - Hamburg). The entire design workflow is presented, focusing the attention on the subsystems design module, an in-house tool named ASTRID, developed at Politecnico di Torino. ASTRID is conceived to design both conventional and innovative systems, as hybrid-electric propulsion systems and More Electric and All Electric architectures. In particular, from the design modules of the proposed environment, system masses and secondary power levels are obtained, hence pointing out the system design effects on aircraft weights and fuel consumptions. Two case studies are presented. The first one refers to the preliminary design of a general aviation aircraft equipped with a hybrid-electric propulsion system. Several variants are designed varying the degree of hybridization, meant as the ratio between the electric power and the total propulsive power. The second case study is centered on four 90-passengers civil airplane designs with the same stakeholders requirements but different on-board systems technology levels - i.e. ranging from a conventional architecture to the All Electric Aircraft, passing through two More Electric configurations. Each design affects differently the aircraft empty weight and the required mission fuel. At the end of the designs, it is assessed that a high degree of hybridization, around 35%, entails a drastic fuel reduction, marking the significant benefits of this innovative technology. Concerning the second case study, the most innovative concept, the All Electric Aircraft, is characterized by a significant fuel reduction due to the more efficient power off-takes and a lower empty weight compared to the traditional architecture, hence returning a lower Maximum Takeoff Weight.

Advanced turboprop multidisciplinary design and optimization within AGILE project

The present paper deals with the design, analysis and optimization of a 90 passengers turboprop aircraft with a design range of 1200 nautical miles and a cruise Mach number equal to 0.56. The pres ncribed aircraft is one of the use cases of the AGILE European project, aiming to provide a 3rd generation of multidisciplinary design and optimization chain, following the collaborative and remote aircraft design paradigm, through an heterogenous team of experts. nThe multidisciplinary aircraft design analysis is set-up involving tools provided by AGILE partners distributed worldwide and run locally from partners side. A complete design of nexperiment, focused on wing planform variables, is performed to build nresponse surfaces nsuitable for optimization purposes. The goal of the optimization is the direct operati nng ncost n, nsubject to wing design variables and top n- nlevel aircraft requirements.

Development of a new conceptual design methodology for parallel hybrid aircraft

In this paper, an innovative methodology for the conceptual design of hybrid-powered airplanes is proposed. In particular, this work focuses on parallel hybrid architectures, in which the thermal engine is mechanically coupled to an electric motor, both supplying propulsive power during a limited number of flight phases, e.g. during takeoff and climb. This innovative solution is the subject of several studies being carried out since the current decade. In this paper, a brief overview of the works conducted by other researchers is provided. Then, an overall aircraft design methodology is proposed, which is derived from the most renewed design algorithms. The original contribution of this work is represented by the development of a methodology for the design of hybrid propulsion systems. Moreover, the proposed method is integrated within a global aircraft design methodology. In particular, several effects of the innovative system on the entire aircraft are considered, for instance the variation of the empty mass or the impacts on fuel consumption. The paper ends with some case studies of the proposed design methodology, and a discussion of the obtained results is provided.