Slides at the end of the pitch describe how RR feels it has solved all the issues related to the uprated A350-1000 engine and calls the Trent XWB "the most advanced civil turbofan". How's that for boldness?
lightsaber From United States of America, joined Jan 2005, 10646 posts, RR: 100 Reply 3, posted (1 year 6 months 1 week 2 days 8 hours ago) and read 4648 times:
I want to know how RR can increase rotational speed 6% *and* grow the core. That changes the blade mach number which changes:
1. Profile optimization (mach # control in the compressors and turbines)
2. Peak mach number (which impacts blade design).
I like how a couple hundred million dollars of engineering is passed off as easy. That will be fun work...
Quoting ferpe (Reply 2): One can sense that RR is really happy with their situation on the TXWB:
I would be happy too.
The two stage intermediate turbine should pay high dividends. How I would like to know the new turbine inlet temperatures... (I do not have the rumor mill to find out that level of proprietary detail.)
AA737-823 From United States of America, joined Mar 2000, 5333 posts, RR: 11 Reply 4, posted (1 year 6 months 1 week 2 days 8 hours ago) and read 4648 times:
Now, if they can only get it to run without leaking oil into itself and catching fire... poor Qantas.
All the advanced tech in the world doesn't do you any good when you've got portions of your turbine at the bottom of the Pacific.
ferpe From France, joined Nov 2010, 1766 posts, RR: 57 Reply 5, posted (1 year 6 months 1 week 2 days ago) and read 4307 times:
Quoting lightsaber (Reply 3): I want to know how RR can increase rotational speed 6% *and* grow the core. That changes the blade mach number which changes:
1. Profile optimization (mach # control in the compressors and turbines)
2. Peak mach number (which impacts blade design).
Isn't that the point, IMO the original idea to make the 93klbf variant was to spin the engine faster without changing the profiles, this would have introduced a mismatch per your post. Now they touch=enlarge the core (how they do that I don't know, that means increase mass flow, does not have to mean increased radial dimensions) then they can change the blade profiles as there should be less commonality anyway with the 84k version.
Could they "increase the core" by just spinning it faster and retuning all the blades, thus leaving all the castings the same (perhaps with tuned stator vane aero)?
Thank you most kindly for drawing out attention to this. Sort of answers a whole host of questions left hanging from the last time, but replaces them with some more specific ones such as
Quoting lightsaber (Reply 3): I want to know how RR can increase rotational speed 6% *and* grow the core. That changes the blade mach number which changes:
1. Profile optimization (mach # control in the compressors and turbines)
2. Peak mach number (which impacts blade design).
To which question one can add, and maintains the same SFC, presumably TSFC.
Another point of interest from the slides is: 2 stage IP turbine for efficiency and growth
We knew about the efficiency bit, but the growth is interesting. Growth, presumably beyond 97k and how far and what for????? Is the 35J about to grow too?
But very very interesting.
Also does the article mean a static test engine for over 40 hours at over 92k or the flying engine at 92k? I presume the former, but the way the article is written it could be the latter.
ferpe From France, joined Nov 2010, 1766 posts, RR: 57 Reply 7, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 4043 times:
I have one additional question for an engine like the TXWB 97k:
1. The take-off thrust is 97klbf they day when max thrust is needed (which is less then 5% of it's time).
2. The cruise thrust (where the engine spends more then 95% of it's time and where the fuel consumption is really important) for a 35J should be around 15klbf per engine dependent on how much fuel=weight has been burned.
How are those 2 widely different conditions playing into the optimization of the engine? IMO the cruise thrust must be the primary optimization point for e.g. the aero in the engine with the max thrust being a case of "yes it works". The variable guide vanes and (stopped) bleeds can help but the engine must be tuned to run at pretty suboptimal SFC at high thrust settings?
So then what % RPM diff does a 97 to 15 klbf thrust change represent in a Trent (i.e. how different are the working Mach numbers for the blades between max and cruise thrust?). I understand the different spools will not follow each other 100% but lets take the fan/LP spool. It is not a linear relationship IMO; 100% to 75%?.
astuteman From United Kingdom, joined Jan 2005, 9135 posts, RR: 96 Reply 8, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 4024 times:
Quoting Revelation (Thread starter): Slides at the end of the pitch describe how RR feels it has solved all the issues related to the uprated A350-1000 engine and calls the Trent XWB "the most advanced civil turbofan". How's that for boldness?
Bold?
The TXWB is easily the most recent large turbofan in development.
If it isn't the most advanced, they want shooting. Never mind "boldness"
Many thanks for the article link by the way
Quoting lightsaber (Reply 3): I like how a couple hundred million dollars of engineering is passed off as easy
SchorschNG From Germany, joined Sep 2010, 442 posts, RR: 0 Reply 9, posted (1 year 6 months 1 week 1 day 17 hours ago) and read 3910 times:
Interesting that most parts are not produced in the UK, but somewhere else.
Another batch of blue collar jobs going offshore.
Will entire UK work in accounting in the future?
If the Trent XWB is successful, I expect a slightly shrinked version for the future A380-900/800R.
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