Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
CFM (GE/Safran) Open The Book On The LeapX  
User currently offlinekeesje From , joined Dec 1969, posts, RR:
Posted (4 years 1 month 2 weeks 17 hours ago) and read 4710 times:

Remarkable open interview of John Croft with Leap programme director Ron Klapproth. Lots of details on technology, time table, C919 vs A320/737, and interesting trade-offs between BPR & weight etc. Enjoy

http://www.flightglobal.com/articles...rving-no-leap-before-its-time.html

CFD & wild blade shapes enter the core engine..



6 replies: All unread, jump to last
 
User currently offlineBurkhard From Germany, joined Nov 2006, 4361 posts, RR: 2
Reply 1, posted (4 years 1 month 2 weeks 17 hours ago) and read 4690 times:

Thanks for sharing. They still have a lot to do if they really want it in service in 2016 already, not much time left.

User currently offlinekeesje From , joined Dec 1969, posts, RR:
Reply 2, posted (4 years 1 month 2 weeks 9 hours ago) and read 4372 times:

Quoting Burkhard (Reply 1):
They still have a lot to do if they really want it in service in 2016 already, not much time left.

They say they've working on it for 12 yrs already.

A related article on the GTF, PW, IAE, RR

P&W's commercial engines senior vice-president of sales, Bob Keady, declined to comment on any GTF development that IAE could undertake. However, he says that from P&W's perspective an advanced version of the engine could feature improvements to the core, such as newer-generation materials, and increased bypass and pressure ratios.

http://www.flightglobal.com/articles...sition-on-future-narrowbodies.html


User currently offlineFly2HMO From , joined Dec 1969, posts, RR:
Reply 3, posted (4 years 1 month 2 weeks 8 hours ago) and read 4317 times:

Quoting keesje (Thread starter):
CFD & wild blade shapes enter the core engine..

Interesting. I wonder what the stators look like, I'm assuming they have a 3D airfoil as well.


User currently offlinelightsaber From United States of America, joined Jan 2005, 12431 posts, RR: 100
Reply 4, posted (4 years 1 month 2 weeks 6 hours ago) and read 4208 times:
Support Airliners.net - become a First Class Member!

Overall a slightly different engine than I was expecting. This isn't a bad thing, it is just my 'guess' on the state of GE technology. I will 'tune my understanding' as more information becomes available.

The bypass ratio is higher than I expected in a non-GTF. (around 11:1 per the link)

Quote:
Klapproth says the X1C fan will have a 190.5cm (75in) "plus or minus an inch" diameter with 18 blades, compared with 36 titanium blades for a CFM56-5C and 24 blades for a CFM56-7B.



I want to see that fan. I have to admit I haven't seen concepts dropping to 18 blades (I'm not in fan development... )

Quote:

Combined with a new lighter fan containment structure, total weight savings will be 455kg (1,000lb) per aircraft, says CFM. Bypass ratios for re-engining programmes might be 9-10:1, says Klapproth.

1,000 lbm per aircraft?!? That is *far less* weight reduction than what I was expecting. Hmmm... so there is room for the GTF.    Seriously, IAE (if that is the GTF path forward) will have to do a bit in weight reduction to stay competitive.

Quote:
The X1C will have a 10-stage HPC (1-4 are blisks, 5-10 are blades)

Bummer... I expected 8 BLISKS and 2 blades.   So if anyone tells me GE has a plan to cut fuel burn ~1%, I'm going to be guessing the LEAP-X HPC is going more BLISK!   

Quote:
CFM International says open rotor by itself can deliver as much as a 26% reduction in fuel burn over today's models.

Which is 10% below the LEAP-X. Interesting... but I think there is far more work ahead on shrouded fans that will make it so that the GTF and Open rotor have similar economics.   

I expect the engine front to be nothing but noise before Farnborough. But at that airshow expect to hear about the A320 and 737 re-engine.

Quoting Fly2HMO (Reply 3):
Interesting. I wonder what the stators look like, I'm assuming they have a 3D airfoil as well.

That is interesting. I wonder if they will make the final design.

Lightsaber



I've posted how many times?!?
User currently offlinekeesje From , joined Dec 1969, posts, RR:
Reply 5, posted (4 years 1 month 1 week 6 days 21 hours ago) and read 4074 times:

Quoting lightsaber (Reply 4):
I want to see that fan. I have to admit I haven't seen concepts dropping to 18 blades (I'm not in fan development... )

A picture is in the flightglobal test stand pcture. A demo was on Le Bourget too. 3D woven RTM CRFP blades with Ti bird cutters.



User currently offlineparapente From United Kingdom, joined Mar 2006, 1509 posts, RR: 10
Reply 6, posted (4 years 1 month 1 week 6 days 20 hours ago) and read 3995 times:

This is what I wrote yesterday in opening a thread that apparently no one wanted to comment on - it seems they do today so I will cut and paste.

There is (I think) a very interesting set (3) of new articles published in Flight International.
http://www.flightglobal.com/articles...ercial-engines-special-report.html


To my eye they go a long way to explaining the thinking of the various players in this market.The Leap-x consortium's thinking is very openly explained (3 stages of development) with the different technologies involved.Also the timelines required.It is very interesting to note that they (like RR) see the ultimate development as a contra rotating open rotor.

The IAE position is somewhat less clear but of course until (not if) P&W and RR resolve workshare these two players will be unavailable for detailed comment.

However one cannot help but notice 2 points.

1.That GE see the way forward as scaling new technology of large engine design down to the smaller engine (which is RR's position)

2.That to get to the ultimate target (2025) 25% reduction in fuel burn it has to be contra rotating open rotors. (Rolls' position).

Yet when you look at Rolls' 15 -50 document thay clearly state that to achieve this (OR) one requires a planitary gearbox to keep the open rotors operating efficiently.

Thus perhaps the positions/technologies of P&W and RR are not that far apart when considering the "end game"ie when the all new aircraft are built. I can see why someone recently suggested that the 2015 engines were "stopgaps".
the cores won't be but perhaps the fans/cowlings will.


Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
Book The Cook Selections? posted Mon Aug 10 2009 17:09:56 by FLY777UAL
The Book Value Of Used 772 - G-YMMM (BA) posted Tue Jun 23 2009 05:00:32 by VV701
Is The Hatch On Top Open .. posted Fri Aug 8 2008 04:31:56 by HAMAD
Does EU Open Skies Abolish The Shannon Stop? posted Thu Mar 22 2007 15:50:50 by ORDTerminal1
QR Still Open To Ordering The 787 posted Tue Feb 27 2007 15:13:35 by NYC777
Finally... A Book On The Tupolev Tu-144! posted Sat Dec 3 2005 02:10:05 by Alberchico
Tempelhof To Stay Open Until (min) The End Of 2007 posted Sat Nov 26 2005 00:07:16 by TheSonntag
Was The B717 The Shortest Line Open? posted Tue May 10 2005 15:48:53 by Squirrel83
The A-B-C Book - Availability posted Tue Dec 14 2004 09:21:20 by HAWK21M
SQ Raffles Class "Book The Cook" posted Mon Jan 12 2004 04:42:26 by Easyjet