Design and Analysis of the Controland Stability of a Blended WingBody Aircraft

Abstract: Future aircraft generations are required to have higher performance and capacities. This achievement should be fulfilled with the minimum cost and environmental impact. This calls for the design of new unconventional configurations, such as the Blended Wing Body (BWB), a tailless aircraft which integrates the wing and the fuselage into a single lifting surface. It has been proven in previously published works that this concept is feasible, has an efficient economical performance and is a promising candidate for solving the current air traffic problems, despite its challenging control and stability features. Moreover, the size of the vertical surfaces, such as the winglets, condition the radar detectability of the BWB model, especially for military missions. The goal of the department of Aeronautical and Vehicle Engineering at the Royal Institute of Technology (KTH) and of the department of Air Transport Systems of the German Aerospace Centre (DLR) is to investigate new ways to improve the conceptual design process of the aircrafts in a multidisciplinary environment. In order to design future unconventional aircraft configurations (such as the Blended Wing Body), the CEASIOM (Computerised Environment for Aircraft Synthesis and Integrated Optimisation Methods) geometry module, AcBuilder, is replaced and enhanced by implementing the Common Parametric Aircraft Configuration Scheme (CPACS), developed by the DLR as a basis technology. CPACS is meant to become a unified software framework to allow the sharing of the work and information, making it accessible for every person. It requires an implementation of the software modules in a framework using a common language for all the tools, in order to make later alterations of this framework easier. A detailed research of the latest developments and advances in the BWB concept was performed in order to identify the main principles and best design options. Afterwards, by using the implemented improved tool CPACSCreator (CC) based on CPACS, instead of Acbuilder, a BWB aircraft baseline was designed. The aerodynamic behaviour and performance of this model were then analyzed with the aid of the improved CEASIOM platform, with an special emphasis on its control and stability features. This analysis enables to improve the baseline design and the allocation and size of the control surfaces was studied and optimized. The minimum winglet required for a target flight performance was identified, due to its importance for reducing the drag and the radar detectability of the aircraft.