WS-15 is not a VCE. As per Orca it is pretty much a Chinese F-119.
Chinese Engine Development
- Thread starter jackbh
- Start date
I believe your stance is:
- a VCE is a design change enough to get leaked
- therefore WS-15 is very likely not to be a VCE.
However, IMHO, it could be because:
- WS-15 was redesigned as a VCE
- so PLA put it even more under wraps
- and the particular two-stream VCE design isn't as far departed from a traditional low BPR turbofan compared to an ACE
- easier to contain the information
- therefore close to nothing is known about the WS-15.
I would agree with you if the WS-15 were said to be converted to an ACE, but this particular two-stream VCE design is just a traditional low BPR turbofan with a CDFS and more variable stator geometries. It's much easier to achieve compared to a full-fledged ACE.
The reason I would consider this is because a two-stream VCE that's able to adjust bypass:core airflow is how you can have a 10+ engine T/W while also having supercruising as one of the main design focus. A traditional low BPR turbofan like the F119, due to the choice of having supercruising as the main focus, barely has a T/W around 10 and even lower if we include the nozzle. The WS-15 IIRC, somehow, achieves both according to vague rumors.
Edit: nevermind. The F119's T/W isn't even 10. It's approximately 7.x with nozzles, and if they only occupy 10% of the engine's total weight, then there's no way F119 has a T/W of 10 or even slightly close.
I don't recall him saying it, can you link it? I do recall him comparing their rev sounds though.
Besides, isn't Orca not the most reliable when it comes to engine info, especially the WS-15? I have a vague recollection of him getting the specs of WS-10B wrong, although I probably can't find it.
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The F119 T/W ratio is no where near 10 I believe but more or less around 8.
Welp, apparently WS-15's T/W is somehow, 11, according to an episode of Chahuahui.
So unless they decide to go for T/W over supercruise performance (unlikely due to the J-20's relatively light weight and being more supersonically optimised), or they can somehow alter OPR/CPR without being an VCE, I don't see how they can achieve both a 11 T/W and having good SC capabilities without being a VCE.
Edit: or unless they used materials much advanced. Which, definitely is the case whether or not WS-15 is a VCE, but having that much of a difference in T/W, something else is likely going on.
Corrected per my last edit.
Or they chose to to have a low SC speed, limiting it at M1,4 instead of going beyond M1,5. But this is all speculation of course.
And why should we trust what Orca says regarding the Top most secret project of pla after H-20 right now
I mean I get it he lives in Chengdu along with his buddies (the usuals) and gets us some new J-20 photos and serials (mostly misleads and pranks), But he is just a watcher not someone with insider info like pop3 or Yankee
Correct me If I am wrong
What if thanks to the: 1, lower wight of the J-20, 2 better L/D ratio and thus better superonic capability and 3, revised aerodynamic design by the addition of the hump behind the canopy for better transsonic capability on the J-20A leads to an engine need that is different than the F119?
A more conventional engine with a relativity lower militarily thrust (22000-25000lbf) and high wet thrust (37000lbf-39000lbf) with a lower engine weight than the F119 because of more conventional round nozzles and smaller engine core?
Maybe it won't supercruise at more than M1.5 but keeps the engine weight and SFC low?
(Excuse me for bringing the Kaan in this but the CEO of TUSAS said on different occasions that the Kaan SC at Mach 1.4 and for 'hours' (no, not with F110s) perhaps similar trade off in SC speed for longer range/SC endurance for the J-20?)
This is all speculation.
A more conventional engine with a relativity lower militarily thrust (22000-25000lbf) and high wet thrust (37000lbf-39000lbf) with a lower engine weight than the F119 because of more conventional round nozzles and smaller engine core?
Maybe it won't supercruise at more than M1.5 but keeps the engine weight and SFC low?
(Excuse me for bringing the Kaan in this but the CEO of TUSAS said on different occasions that the Kaan SC at Mach 1.4 and for 'hours' (no, not with F110s) perhaps similar trade off in SC speed for longer range/SC endurance for the J-20?)
This is all speculation.
Highly unlikely on the SC part.
The J-20 is quite literally tailor-made for China and SCS operations. That means covering a huge span of territory.
The whole point of supercruising is to, get to somewhere, fast, while not burning obscene amounts of fuel.
It's highly unlikely, IMHO, that the J-20 would sacrifice one of its main design goals, supersonic flight performance and having a slower SC speed, for an even higher T/W when it already has a pretty competitive T/W with WS-10Cs.
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I think you meant this one
Abstract
A new testing research on an existing engine provides an efficient way to explore critical engine technology.A new method is proposed to develop VCE (variable cycle engine) from a conventional gas turbine (turbofan) engine.This paper also presents a configuration promotion project with introduction of selector valve,and puts forward VABI (variable area bypass injector) and rear VABI.The first stage of high pressure compressor is changed to a CDFS (core-driven fan stage).The working principle of the VCE is stated.Based on the components′ performance level of conventional turbofan engine,a primary overall performance project is carried out and a numerical simulation on VCE is conducted.The calculation results show that the thrust can be increased by 5% to 8% in supersonic cruise using single bypass mode.Although specific fuel consumption (SFC) cannot be decreased obviously in subsonic cruise using double bypass mode,the engine inlet air flux can be increased by 5%,so the spillover is reduced and installed performance of the engine can be improved.I got the feeling that the conventional gas turbine in this paper is WS-10 when I read it in detail.