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Blended Wing Body (BWB) Boundary Layer Ingestion (BLI) Inlet Configuration and System StudiesA study was conducted to determine the potential reduction in fuel burned for BLI (boundary layer ingestion) inlets on a BWB (blended wing body) airplane employing AFC (active flow control). The BWB is a revolutionary type airplane configuration with engines on the aft upper surface where thick boundary layer offers the greatest opportunity for ram drag reduction. AFC is an emerging technology for boundary layer control. Several BLI inlet configurations were analyzed in the NASA-developed RANS Overflow CFD code. The study determined that, while large reductions in ram drag result from BLI, lower inlet pressure recovery produces engine performance penalties that largely offset this ram drag reduction. AFC could, however, enable a short BLI inlet that allows surface mounting of the engine which, when coupled with a short diffuser, would significantly reduce drag and weight for a potential 10% reduction in fuel burned. Continuing studies are therefore recommended to achieve this reduction in fuel burned considering the use of more modest amounts of BLI coupled with both AFC and PFC (Passive Flow Control) to produce a fail-operational system.
Document ID
Document Type
Contractor Report (CR)
Kawai, Ronald T.
(Boeing Phantom Works Huntington Beach, CA, United States)
Friedman, Douglas M.
(Boeing Phantom Works Huntington Beach, CA, United States)
Serrano, Leonel
(Boeing Phantom Works Huntington Beach, CA, United States)
Date Acquired
August 24, 2013
Publication Date
December 1, 2006
Subject Category
Aeronautics (General)
Report/Patent Number
Funding Number(s)
WBS: WBS 22-714-05-05
Distribution Limits
Work of the US Gov. Public Use Permitted.
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