Methodology and tools to improve the aerodynamic characterization of high-speed vehicles during the conceptual design phase

Over the last years, innovative concepts of civil high-speed transportation aircraft were proposed. These vehicles have a strong potential to increase the cruise range efficiency at high Mach numbers, due to efficient propulsion units combined with high-lifting vehicle concepts. In this context, the necessity to have a simple and reliable tool for the estimation of the aerodynamic performance of such vehicles is of primary importance in the first phases of the design, when a quick response is needed for each design modification/improvement that is made. The objective of this thesis is to improve the prediction of the aerodynamic performance of a new high-speed vehicle since the conceptual design phase. The goal is to define a new aerodynamic performances characterization routine as complete as possible, capable of supporting a wide range of users and vehicle configurations. The first part of this project focuses on the analysis and description of four preliminary aerodynamic estimation models taken from the literature: their main theoretical aspects, limitations and capabilities have been listed. The next step is to implement them in Matlab, test them with existing aircraft whose main geometric characteristics are known, and compare the results obtained with the available aerodynamic coefficients. Finally, in order to better estimate the aerodynamic behaviour of the aircraft under investigation for the whole mission profile, the basic models have been adapted thanks to corrective coefficients. The analysis focuses on the combined cycle engine launchers, which include hypersonic cruise aircraft, powered by air-breathing propulsion over all or part of their flight mission. In particular, the aerodynamic coefficients of ten different high-speed vehicles are studied, grouped into four different configurational families: Waverider configuration, Blended body configuration, Wing body configuration and Cylinder wing configuration. The main effort of this work was spent on the application to the STRATOFLY MR3 vehicle case study. STRATOFLY MR3 is a Mach 8 waverider configuration that stems from more than a decade of European research activities , under the framework of Horizon 2020 research and innovation programme. In particular, for this vehicle it is possible to estimate the aerodynamic coefficients for a Mach number between 0.4 to 8, for and angle of attack between 1° to 5° and for all operative conditions, including the case in which the engines are switched on or off. Finally, In order to allow any user to take advantage of these results, it was necessary to implement a simple and intuitive Graphical User Interface (GUI). The work are also contributing to the improvement of ASTRID-H, a conceptual design tool currently under development by Politecnico di Torino.