“Blended wing body”的意思、由来-开放百科全书

A blended wing body (BWB or Hybrid Wing Body, HWB^[1]) is a fixed-wing aircraft having no clear dividing line between the wings and the main body of the craft. The form is composed of distinct wing and body structures, though the wings are smoothly blended into the body, unlike a flying wing which has no distinct fuselage.^[1] A BWB design may or may not be tailless.

The potential advantages of the BWB approach are efficient high-lift wings and a wide airfoil-shaped body. This enables the entire craft to generate lift, potentially reducing the size and drag of the wings. A blended wing body can have a lift-to-drag ratio significantly greater than a conventional craft, offering improved fuel economy.

History

The 1924 Westland Dreadnought was built on the basis of the theories of Nicolas Woyevodsky after wind tunnel tests. It stalled on its first flight, severely injuring the pilot, and the project was shelved by the British Air Ministry.

The Burnelli UB-14 was a 1930s American prototype lifting-fuselage airliner designed and built by Vincent Burnelli.

The Miles M.30 "X Minor" of the early 1940s was an experimental aircraft to test the blended wing fuselage design for a proposed large airliner, designated the Miles M.26. The McDonnell XP-67 prototype interceptor also flew in 1944 but did not meet expectations.

NASA studied the concept more recently with a computer stabilized {{convert|17|ft|adj=on}} model (6% scale) called BWB-17, built by Stanford University, which was flown in 1997 and showed good handling qualities.^[2]{{rp|16}} From 2000 NASA went on to develop a remotely controlled model with a {{convert|21|ft|adj=on}} wingspan. This research is focused on establishing the base data concerning the lift, stall and spin characteristics inherent in a Blended Wing Body design.

NASA has also jointly explored BWB designs with the X-48 unmanned aerial vehicle.^[3] Studies suggest that BWB aircraft, configured for passenger flight, could carry from 450 to 800 passengers and achieve fuel savings of over 20 percent.^[2]{{rp|21}} Other suggestions are better access to emergency exits.^[2]{{rp|24}} Unfortunately potential passengers disliked the internal seating arrangements and the program changed its focus toward cargo aircraft.{{citation needed|date=November 2015|reason=this statement is opinion based}}

Characteristics

The BWB form minimises the total wetted area - the surface area of the aircraft skin, thus reducing skin drag to a minimum. It also creates a thickening of the wing root area, allowing a more efficient structure and reduced weight compared to a conventional craft. NASA also plans to integrate Ultra High Bypass (UHB) ratio jet engines with the hybrid wing body.^[4]

The wide interior spaces created by the blending pose novel structural challenges. NASA has been studying foam-clad stitched-fabric carbon fiber composite skinning to create uninterrupted cabin space.^[5]

A conventional tubular fuselage carries 12-13% of the total lift compared to 31-43% carried by the centerbody in a BWB, where an intermediate lifting-fuselage configuration better suited to narrowbody sized airliners would carry 25-32% for a 6.1% - 8.2% increase in fuel efficiency.^[6]

Potential advantages

Potential disadvantages

At an American Institute of Aeronautics and Astronautics meeting on March 28, 2018 at the University of Washington in Seattle, Boeing’s VP of Product Development and Future Airplane Development Mike Sinnett noted that as the center wingbox is also the passenger cabin, it needs to be tall enough to stand upright, translating into a large transport minimum span for multiple hundreds of passengers.

A concept photo of a blended wing body commercial aircraft appeared in the November 2003 issue of Popular Science magazine.^[14] Artists Neill Blomkamp and Simon van de Lagemaat from The Embassy Visual Effects created the photo for the magazine using computer graphics software to depict the future of aviation and air travel.^[15] The BWB-450, a pre-X-48 concept from the late 1990s, or the X-48A concept from around 2001^[16] may have inspired the photo.{{citation needed|date=November 2014}} The image was subsequently used in emails since 2006 claiming that Boeing has developed a "1000 passenger Jet Liner" (the "Boeing 797") with a "radical Blended Wing design" in direct competition to the Airbus A380.^[17] Boeing denied the claim at the time.^[18]^[19]

See also

References

1. ^Crane, Dale. Dictionary of Aeronautical Terms, third edition. Newcastle, Washington: Aviation Supplies & Academics, 1997. {{ISBN|1-56027-287-2}}. p. 224.
2. ^¹²{{cite article |author= Liebeck, R.H. |url= https://arc.aiaa.org/doi/abs/10.2514/1.9084 |title= Design of the Blended Wing Body Subsonic Transport |journal= AIAA Journal of Aircraft |volume= 41 |issue= 1 |date= January–February 2004 |pages= 10–25 |url-access=subscription}}
3. ^"A flight toward the future." {{webarchive |url=https://web.archive.org/web/20121204000341/http://www.boeing.com/Features/2012/08/corp_x48_08_07_12.html |date=December 4, 2012 }} Boeing, August 7, 2012 Retrieved: November 23, 2012.
4. ^{{cite web|last=Michael Braukus / Kathy Barnstorff|title=NASA's Green Aviation Research Throttles Up Into Second Gear|url=http://www.nasa.gov/home/hqnews/2013/jan/HQ_13-002_ERA_Phase_2.html|publisher=NASA|accessdate=Jan 26, 2013|date=Jan 7, 2013}}
5. ^{{cite web |last=Bullis |first= Kevin |title= NASA has demonstrated a manufacturing breakthrough that will allow hybrid wing aircraft to be scaled up. |url= http://www.technologyreview.com/news/509916/hybrid-wing-uses-half-the-fuel-of-a-standard-airplane/ |work= MIT Technology Review |date= January 24, 2013}}
6. ^¹{{cite web |url= http://aviationweek.com/commercial-aviation/finding-ultra-efficient-designs-smaller-airliners |title= Finding Ultra-Efficient Designs For Smaller Airliners |date= Aug 22, 2016 |author= Graham Warwick |work= Aviation Week & Space Technology}}
7. ^Warwick, Graham. [https://www.flightglobal.com/news/articles/boeing-works-with-airlines-on-commercial-blended-win-213997/ "Boeing works with airlines on commercial blended wing body freighter."] Flight International, May 21, 2007.
8. ^{{cite web |last= Warwick |first= Graham |title= Hear This - The BWB is Quiet! |url= http://aviationweek.com/blog/hear-bwb-quiet |work= Aviation Week |date= Jan 12, 2013}}
9. ^¹{{cite web|author=Russell H. Thomas, Casey L. Burley and Erik D. Olson|title=Hybrid Wing Body Aircraft System Noise Assessment With Propulsion Airframe Aeroacoustic Experiments|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100023399_2010025666.pdf|accessdate=26 January 2013|year=2010}} Presentation {{webarchive|url=https://web.archive.org/web/20130516232013/http://www.aeronautics.nasa.gov/pdf/asm_presentations_status_hwb_community.pdf |date=2013-05-16 }}
10. ^{{cite news |author1=E. R. Galea |author2=L. Filippidis |author3=Z. Wang |author4=P. J. Lawrence |author5=J. Ewer |title=Evacuation Analysis of 1000+ Seat Blended Wing Body Aircraft Configurations: Computer Simulations and Full-scale Evacuation Experiment |work=Pedestrian and Evacuation Dynamics |isbn=978-1-4419-9724-1 |year=2011 |pages=151–61 |doi=10.1007/978-1-4419-9725-8_14}}
11. ^{{cite web |url=http://www.evacmod.net/?q=node/2080 |first= Ed |last=Galea |title=Evacuation analysis of 1000+ seat Blended Wing Body aircraft configurations |type=video |website=evacmod.net |accessdate=August 25, 2015 }}
12. ^{{cite news |url= http://www.imeche.org/news/news-article/boeing-not-convinced-by-blended-wing-aircraft-design-16061502 |title=Boeing not convinced by blended wing aircraft design |date=June 16, 2015 |work= Institution of Mechanical Engineers}}
13. ^--> For the same payload, a cargo BWB has more wingspan but is heavier empty and it is not worth it for short missions of around four or fewer hours, while long haul routes would see a benefit. However, the larger wing span may conflict with airport compatibility and containers quick loading: changing the infrastructure would need an economical improvement of more than 20% over current designs, except maybe for a military cargo aircraft. A tube-and-wing design is easier to stretch or shrink for several sub-types sharing the large development costs while a BWB can hardly be modified by its most expensive non-constant section in a non-constant way.{{cite news |url= https://leehamnews.com/2018/04/03/dont-look-for-commercial-bwb-airplane-any-time-soon-says-boeings-future-airplanes-head/ |title= Don’t look for commercial BWB airplane any time soon, says Boeing’s future airplanes head |date= April 3, 2018 |work= Leeham News}}
14. ^[https://books.google.com/books?id=5bKyC4K5tMwC&lpg=PP3&pg=PA44#v=twopage&q&f=false "Future of Flight."] Popular Science, November 2003.
15. ^"Future Flight: A Gallery of the Next Century in Aviation." PopSci.com, October 15, 2003. Retrieved: November 22, 2012.
16. ^Chambers, Joseph R. [https://history.nasa.gov/monograph39/mon39_a.pdf NASA SP-2005-4539 "Innovation In Flight: Research Of The NASA Langley Research Center On Revolutionary Advanced Concepts For Aeronautics"]. NASA, August 22, 2005.
17. ^{{cite web |url= http://www.truthorfiction.com/rumors/b/b797.htm |work= TruthOrFiction.com |title=New Boeing 797 Giant "Blended Wing" Passenger Airliner-Fiction! |date= March 17, 2015}}
18. ^Christensen, Brett M. "Boeing 797 Hoax" Hoax-Slayer, April 19, 2012. Retrieved: November 22, 2012.
19. ^Baseler, Randy. "Air mail." Boeing blogs: Randy's Journal, November 1, 2006. Retrieved: November 22, 2012.

History

Characteristics

Potential advantages

Potential disadvantages

See also

References

Further reading