Conceptual Design Methodology for Blended Wing Body Aircraft

276 Pages·2016·5.6 MB·English

PhD Thesis
Conceptual Design Methodology for
Blended Wing Body Aircraft
Paulinus Peter Chukwuemeka Okonkwo
May 19, 2016
School of Aerospace, Transport and Manufacturing Cranfield University
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Conceptual Design Methodology for
Blended Wing Body Aircraft
PhD Thesis
For obtaining the degree of Doctor of Philosophy in Aerospace
Engineering at Cranfield University
Paulinus Peter Chukwuemeka Okonkwo
May 19, 2016
Supervisor: Prof Howard Smith
School of Aerospace, Transport and Manufacturing Cranfield University
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Copyright c Cranfield University 2016. All rights reserved. No part of this publication
(cid:13)
may be reproduced without the written permission of the copyright owner.
Cranfield University
Department of
Aerospace Engineering
TheundersignedherebycertifythathehasreadandrecommendtotheSchoolofAerospace,
Transport and Manufacturing for acceptance a thesis entitled “Conceptual Design
Methodology for Blended Wing Body Aircraft” by Paulinus Peter Chukwue-
meka Okonkwo in partial fulfillment of the requirements for the degree of Doctor of
Philosophy.
Dated: May 19, 2016
Supervisor:
Prof Howard Smith

Abstract
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
realisticconceptualdesignsynthesisandenablestheexplorationofthedesignspaceofthis
novel class ofaircraft. Thedevelopedtoolwaseventually appliedtotheconceptualdesign
synthesis andsensitivity analysis ofBWB aircraft todemonstrate its capability, flexibility
andpotential applications. Theresults obtained conformstothepattern established from
aCranfieldUniversitystudyontheBlendedWingBodyAircraftandcouldthusbeapplied
in conceptual design with a reasonable level of confidence in its accuracy.
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Dedication
This thesis is dedicated to my late parents, Mr and Mrs Edwin Okonkwo who despite all
odds worked tirelessly to give me a decent life.
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