Posted on 01/11/2015 2:38:11 AM PST by gortklattu
Improving fuel efficiency, even by one percent, on the world's most popular plane makes a huge difference. After achieving success with the first 737 winglet, the team was challenged with finding ways to make the 737 MAX even more efficient.
Boeing video at the source
ping
Why aren’t they putting the “winglets” on the 787 if it improves fuel efficiency? Do different engines mean the 787 won’t require it?
Richard Whitcomb was one of them. The Area Rule, Supercritical airfoil, and the Winglet. It is interesting to see Oshkosh Attendee's with their name tags on, and walking by and just happened to reading one of a "Richard Whitcomb" in attendance when he was alive.
https://en.wikipedia.org/wiki/Richard_T._Whitcomb
What is interesting is Boeing has not opted for the Pratt and Whitney Geared Turbofan Engine which could yield them a 15% reduction in fuel consumption on the 737...
That's why Airbus is proposing the A321neoLR (New Engine Option--Long Range)--essentially an A321 with new engines, new winglets (Airbus calls them sharklets) and extra fuel capacity that pushes the range to 3,900 nautical miles, which makes the plane a perfect one-for-one replacement of the aging Boeing 757-200. And not surprisingly, American Airlines, Delta Air Lines and United Airlines are all interested, given all three airlines now fly A320 Family variants (Delta got theirs when they merged with Northwest Airlines).
Boeing used a raked wingtip design on the 787 to achieve the same fuel savings--similar to what they did with the 777-200LR and 777-300ER. You can clearly see the raked wingtips in this photo:
I thought the video was pretty cool... until the Boeing engineer started spouting crap about reducing carbon emissions.
We ARE carbon. Get used to it.
We eat carbon. We burn carbon. We exhale carbon. We fart carbon. We poop carbon.
The more carbon, the better.
Plants, trees, and and other green growing things love it. They are constantly thanking us. Listen closely - they’re saying, “Thank you, sir. May I have some mo’ please? Oh, by the way, here’s some oxygen I farted. Might you be needing that, sir?”
While Boeing has a patent I believe on their raked tip, one may ask how and why they got it given NASA’s work on their “Shark-Tips” and Dornier’s “Sheared” Wingtip...
Wings on the 787, and the 777, are designed to be efficient from the get go, winglets wouldn’t make a bit of difference.
what is geared about it?
I worked on GG4 and GG8 engines for a few years, they both had dual spool low and high compressors
Geared?? fixed N1 and N2??
Their new line "Pure Power" engines are Geared Turbofans. A gearbox between LPT spool (N1 if my memory is correct) so that spool and spin in a more efficient range and than the fan. It utilizes a highly patented gearbox with a clever way of dealing with core vs/ fan misalignment issues, it is hard to explain, it is if the whole planetary mechanism floats in space...
Just as Copernicus and Newton said.
Yes, and the earth is flat.
Winglets/raked tips are used to increase efficiency of a wing. There are many companies installing them, or improved versions, on dozens of types of aircraft. When originally built, they were ALL considered to be state of the art....but the art changes.
Improvements in winglet/raked tip design, materials and manufacturing will continue, including folding sections, and will eventually be retrofitted onto the Boeing widebodies.
Yes, and the earth is flat.
Winglets/raked tips are used to increase efficiency of a wing. There are many companies installing them, or improved versions, on dozens of types of aircraft. When originally built, they were ALL considered to be state of the art....but the art changes.
Improvements in winglet/raked tip design, materials and manufacturing will continue, including folding sections, and will eventually be retrofitted onto the Boeing widebodies.
crap
Good for the airlines....customers, not so much.
that sounds like it is limiting N1...unless it is actually increasing N1, that would mean a higher temp ignite I suppose for N2 or greater fuel usage to get N2 going
Since the Dual Spool method might not allow in enough air, theoretically, into the high compressor, if it is geared to spin at a faster rate than dual spool physics would allow...wont that create compressor stalls??
I forgot the bypass outlets actual name, the exhaust on the Low compressor side that allows excess air to exhaust, BLEED VALVES? P&W name for them anyways
Hmmm. gear N1 to go Faster, closer to N2 in speed...
IIRC, a GG4 N2 would top out, full throttle, no afterburner at about 12K to 13K, N1 would be 10K to 10.5K, increase that to 11K or maybe 11.5K with N2 still about 12K to 13K...you certainly get forced air!
I remember after installing one in Peru, we had bad compresor stalls, it scared me to death, I kept the peruvians from standing on the side of the engine, didnt want to see a compressor disk go flying 1/4 mile through me!
I did it for aero derivitives for power generation, power companies. Same engine, just blocked in a frame, blew exhaust on a free turbine connected to a generator, think of a windmill
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