Transitional Strategy for Annular Lift Fan Aircraft to Lower the Momentum Drag and Pitching Moment
Publication: Journal of Aerospace Engineering
Volume 34, Issue 2
Abstract
The annular lift fan aircraft is a new conceptual vertical takeoff and landing (VTOL) vehicle for which the tremendous momentum drag and pitching moment in transition is a big problem to overcome. In this study, different strut configurations and transitional strategies for the annular lift fan aircraft are numerically investigated using computational fluid dynamics (CFD) software. The results show that the longitudinal struts can significantly reduce the oscillations of lift and drag caused by the interactions between the radial struts and the incoming flow and that the gliding transition strategy reduces the total required thrust by 47% without the need for a skirt. This gliding transition is also faster, taking only about 20 seconds to complete because part of the thrust can be used for the forward acceleration.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
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Information
Published In
Journal of Aerospace Engineering
Volume 34 • Issue 2 • March 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Apr 28, 2020
Accepted: Oct 9, 2020
Published online: Jan 5, 2021
Published in print: Mar 1, 2021
Discussion open until: Jun 5, 2021
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