More likely Minnie Chan
J-20 5th Generation Fighter VII
- Thread starter siegecrossbow
- Start date
- Status
More likely Minnie Chan
somehow I feel we are going to see this news again in Chinese sometime soon...
The reason, as it turns out, is the unresolved problem of a sharp drop in the thrust of the WS-15 engine when the temperature of the turbine of the power plant approaches the operating parameters.
Sounds kind of funny. Does the article implying there won't be sharp drop if the temperature is cold, not approaching operating parameters?
When will that condition be met?
When will it not approaches operating parameters?
Lol, shouldn't WS10 see this type of problem why need to wait WS15 to see this obvious condition?
Sounds Bogus to me.
Well we do not know if WS-15 uses the same kind of turbine blades. It probably does not since it needs to operate at higher temperatures to achieve a higher thrust-to-weight ratio in the first place. It could have limitations on the alloys used, the coatings, or the cooling system. Those kinds of active cooling systems can be a real bear to implement in practice. Still, given that rocket engines also need to have active cooling with film cooling I would have expected them to dominate this technology but who knows.
The implication is that the WS-15 simply doesn't work, since being capped at 1350 degrees Celsius puts the operating cap significantly below that of a WS-10 or F135.
The only way I think this could possibly be true would be if the turbine blades were in a state of semi-melting at that temperature, which seems improbable. Turbines tend to be able to run at higher than their design temperature, but with the expectation that the turbine will be destroyed afterwards.
Or the suggestions of 1350 C limit is made up because the guy who wrote the article is strangely in possession of a piece of information not found anywhere else in public and he wouldn't really have any way of knowing. He doesn't work at the developer. Possibly even misinformation.
The first WS-15 was allegedly finalised and either completed or built to a stage where they realised it wasn't as good as they could make it with more modern techniques. This was during an era where China finally mastered several more turbofan technologies and materials. They redesigned the WS-15 following this with all the newly available resources and lessons from correcting initial WS-10 engines to A/B/x onwards, to build what was leaked as another clean sheet design.
If WS-10 can easily handle much higher operating temperatures and the design on that WASN'T based on the Al-31 but rather the core of a CFM engine, how could a superior design taking place over decade beyond the WS-10's possibly be stumbling on a relatively simple engineering problem. The alleged reason given here for the temperature limit is fuel accumulation. That's not a difficult problem and not a problem in any Chinese engine developed in the past. It doesn't really depend on thrust. The traditional problems have in the past always been about materials, fan blades, software, and manufacturing at scale. Never been about plumbing, calibration, fuel injectors or design.
What's more possible? Some random article's author made that up and hasn't given a single source or piece of reasoning. Or somehow the engineers could figure out the most difficult problems but struggling with the easiest.
The WS-15 is planned to make service around 2025. If this allegation from random internet user is accurate, we shouldn't see the WS-15 ready until after 2030. It would take years just to correct the problem on the same design and about a decade to redesign and go through the entire process. I doubt either is true and the WS-15 is only working on the manufacturing side of problems now.
Last edited:
I think the source might be just regurgitating outdated information. We know that China has made a break through back in 19/20 for a F class gas turbine by dong fang electric. Its only 50MW so it is highly likely to be an aero derivative. Given that the turbine entry temp for F class is around 1400C, and that the mean time between failure for commercial generator should be pretty high, logic would dictate that the turbine blade manufacturing technology by China should be able to achieve the WS-15's requirement. My guess is that they got the process for WS-15's blades figured out earlier, and then applied it to the F class turbines.
I'm just calling bullshit on the 1350C cap claim. The AL-31, FFS, has an inlet temperature of 1400C.
broadsword
Brigadier
I think the temperature tolerance issue is a solvable problem, if it has not been solved by now. I doubt the engineers would set a target that would be so excessively high that it would take them five years to overcome.
- Status