The J-20-engine discussion is over and other speculative topics ... to separate from the J-20-news !

[Figaro]

We are in 2018 could you find me a person in this world that does not know Google, and all its products, especially Google Translate. U cannot find other than those who are more than 90's years old. English is not my mother tongue as U can guess, but when I compare translation into french, most of the time GT is far to be accurate. And sometimes its translation mislead you. It is a robot, and not a man. It is obvious that I tried with GT, but I don't find it very interesting. For that reason I ask a simple translation.

Google translate is generally pretty poor for character based languages like Chinese ... especially for colloquial terms.

 

[sinait]

Google translate is generally pretty poor for character based languages like Chinese ... especially for colloquial terms.

Those who think you can just dump it in wholesale and have a perfect translation out will be disappointed.
So now that he knows that it needs a bit of intelligence and effort to get a good translation and instead of being appreciative, he rants.

It needs some work where the output text appear nonsensical or reversed and involves choosing from several texts with similar meanings that is optimum in this context.
I waited some time before I decided to contribute, preferring to let Chinese members do it.
Chinese technical text and jargon not my cup of tea, just like medical terms would be intelligible to most of us.
Google did a decent job considering the difficulties.
.

 

[foxhoundbis]

So, was what I got out from Google Translate simple and clear enough for you.?

Nope!

... so I think Google did a good job.

No one doubts.

I would think priority for Google would be for Chinese to English, so Chinese to French may not be as good.

I never said that I used chineese to french. Most of translate tools are optimized for English tongue at first. I did not dare french.

Those who think you can just dump it in wholesale and have a perfect translation out will be disappointed.

AFAIK, no one asks the perfection. However a translation is to translate an idea, from one tongue to another. This is not paste of words like a collection of 'spaghetti'. As I said GT is a robot, it is fine for some basic purpose, and in fact a good job of Google. However it does not suit for a complex text, and tongue, like it was posted. My purpose was to understand whether the WS-15 is ready or not. Is this engine still in test ? If yes, until when ? The J-20 will be equipped with this engine, so when ? I noticed that most of the time regarding chinese military news, it is always a matter of 'unknown' fans, if not 'fakes' on Internet went out of nowhere. No straightforward news of chinese's media mainstream networks. I don't know how to think.

 

[LKJ86]

I noticed that most of the time regarding chinese military news, it is always a matter of 'unknown' fans, if not 'fakes' on Internet went out of nowhere. No straightforward news of chinese's media mainstream networks. I don't know how to think.

This is the difference between China and other countries.
The ministry of national defense of China often confirms the informations at last minute, when almost everyone has known that.
So, you would often find many surprises.
Just like: J-20, Type 002/3...

 

[sinait]

Nope!
No one doubts.

I never said that I used chineese to french. Most of translate tools are optimized for English tongue at first. I did not dare french.

AFAIK, no one asks the perfection. However a translation is to translate an idea, from one tongue to another. This is not paste of words like a collection of 'spaghetti'. As I said GT is a robot, it is fine for some basic purpose, and in fact a good job of Google. However it does not suit for a complex text, and tongue, like it was posted. My purpose was to understand whether the WS-15 is ready or not. Is this engine still in test ? If yes, until when ? The J-20 will be equipped with this engine, so when ? I noticed that most of the time regarding chinese military news, it is always a matter of 'unknown' fans, if not 'fakes' on Internet went out of nowhere. No straightforward news of chinese's media mainstream networks. I don't know how to think.

Nope!

Tsk tsk, what a rude and uncouth tone used.
Some would have thought I was paid by you to post the translation and you were unsatisfied with the job done.
Or did somebody told you that China owe you a prompt official update on their engine development?
.

 

[foxhoundbis]

Or did somebody told you that China owe you a prompt official update on their engine development?
.

China owes me ? Owes me what ? First of all Iam not chinese, moreover I never asked the moon, just basic news.
However as LKJ explained above, regarding China is quite normal, I forgot that with China is still miser regarding this kind of news.

 

[LKJ86]

China owes me ? Owes me what ? First of all Iam not chinese, moreover I never asked the moon, just basic news.
However as LKJ explained above, regarding China is quite normal, I forgot that with China is still miser regarding this kind of news.

1. If you want basic news, you can search the military websites, like Janes and so on.
2. Doing a good translation is not a easy job. You need some knowledge of military affairs, network argots, and so on. It takes time.
3. If you don't satisfy the translation, you can try other ways. But the person who provides the translation doesn't owe you anything. Nothing is taken for granted.

 

[gambit]

AFAIK, no one asks the perfection. However a translation is to translate an idea, from one tongue to another. This is not paste of words like a collection of 'spaghetti'. As I said GT is a robot, it is fine for some basic purpose, and in fact a good job of Google. However it does not suit for a complex text, and tongue, like it was posted. My purpose was to understand whether the WS-15 is ready or not. Is this engine still in test ? If yes, until when ? The J-20 will be equipped with this engine, so when ? I noticed that most of the time regarding chinese military news, it is always a matter of 'unknown' fans, if not 'fakes' on Internet went out of nowhere. No straightforward news of chinese's media mainstream networks. I don't know how to think.

You are asking for the impossible. Of the Chinese members in this forum, and their supporters, NONE of them served in the military and/or have experience in related fields. As such, they cannot explain complex technical issues involved. In the past, some tried and they ended up butchering the technical ideas in explaining and moving so far out that they ended up defying the laws of nature in trying to hype up Chinese accomplishments.

At the theoretical level, a turbine, aka 'jet', engine, is the same as the internal combustion engine in your car. We have an enclosed chamber, air, fuel, a fuel atomizing method, an air-fuel mixture method, an ignition source, and finally a method to control and exploit the explosion.

To move a car, we direct the fuel-air explosion into mechanical actions. Pistons, connecting rods, crankshafts, transmission, and so on...

To move an aircraft, we direct the fuel-air explosion into atmosphere, and Newton's laws takes over, to simplify a bit.

So then why is it -- if at the theoretical level both ideas are the same -- the turbine engine is so difficult to design, engineer, operate, and maintain? If you look at both methods, it seems the turbine engine should be easier to do all those things. Theoretically, we are not translating the explosion into mechanical actions. We are simply venting to atmosphere.

The theory is actually correct. The turbine engine is CONCEPTUALLY simpler precisely because we are not translating the force of the explosion into mechanical actions to the extent of the automobile version of the internal combustion engine.

In the auto version, we have mechanical translations in the up/down (pistons) and rotational (crankshaft).

In the turbine design, we have a rotating core shaft. And that is it.

The problem is HEAT.

Heat in the internal combustion engine design for the car is NOT constant. We have an explosion and then none for one chamber. Same for the other chambers. Now repeat for all chambers. It is called the 'firing order'.

https://en.wikipedia.org/wiki/Firing_order

Look at it another way...Heat and mechanical actions in the automobile version of the internal combustion engine comes in pulses. Because of this, and the lower temperature in the automobile version, materials in the auto version can be less 'exotic' which means easier to manufacture.

https://en.wikiversity.org/wiki/Internal_combustion_engines

Ignition of the fuel in the cylinders produces temperatures of 700°C or more.

https://cs.stanford.edu/people/eroberts/courses/ww2/projects/jet-airplanes/how.html

Inside the typical commercial jet engine, the fuel burns in the combustion chamber at up to 2000 degrees Celsius.

So when we combine constant heat sources with higher temperature, we can see that even though the turbine engine is conceptually easier, the turbine engine is much more difficult to engineer and manufacture due to the demands for more 'exotic' materials that can withstand the constant heat.

- Concept
- Design
- Engineering
- Operation
- Maintenance

The last three items -- regarding heat -- are literally killers of any plan for a combat type of turbine engine.

The MIG-25 and SR-71.

The MIG is famous for its ability to reach Mach 2 or even higher. But it is well known that once the engine was pushed to that performance level, it must be scrapped at mission end. Not rebuilt, but essentially sent back to the manufacturer for disposition, which always means scrap status.

The SR, on the other hand, just needs its engine oil sampled and if there are any maintenance issues involved, line maintenance can be done by high school graduates.

What this means is that we can have high performance at the cost of operation and maintenance, or operation and maintenance at the trade-off of high performance. The SR-71 got all three items -- performance, operation, and maintenance -- done. The MIG-25 does not. When I was active duty and stationed at RAF Upper Heyford, I have friends at RAF Mildenhall who were with Det 4 SR-71 operators. The SR-71 can attain speed of higher than Mach 3+. Everyone knew it then, and everyone knew it now. And the PW J58 engine does not need a rebuilt after each unofficial Mach 3+++ speed run.

Here is an excellent laymen level source to understanding the turbine engine, specifically on the difficulties of heat...

https://www.americanscientist.org/article/each-blade-a-single-crystal

The SR-71 is mentioned along with other military high performance combat aircrafts. The idea that each compressor blade is essentially a SINGLE CONTINUOUS CRYSTAL is mind boggling, to say the least. But this is the problem for any country trying to match the performance level of what have been accomplished by US or by anyone else.

The core would be about 1/3 down the overall length of the entire engine. That means each blade would be 1/4 the height of the man. Now imagine a blade to be a SINGLE CONTINUOUS CRYSTAL.

The J-20 can have the power necessary from its engines, but does the engine design itself have the durability and reliability necessary for the jet to have long term deployment? There were very few SR-71 and yet whenever the need for information, the jet always delivered. That is the level of overall performance the military want and need.

Finally...You will not see anything like what I posted above from the Chinese members here. Nothing I posted is 'classified' secret. There is not a single math equation. And yet, am willing to bet YOUR understanding of the difficulties of designing a high performance turbine engine, civilian and military, just increased dramatically. From this point on, any claim about the WS-15 must be taken with doubts and hold against what you learned about the turbine engine from publicly available sources.

 

[lmjiao]

 

[CriticalThought]

Seriously, I explained the foundation of the turbine engine better than ANY of the Chinese members here can.

This is where you -- in your shortsightedness -- failed to understand. For every participating member, there is an unknown number of silent readers out there who have deeper technical interests than you and your fellow Chinese. It is they -- not you Chinese -- who I focused on. My post 593 will be the starting point about the turbine engine that none of you Chinese will ever be able to provide.

@Deino @The Eagle @WebMaster this guy is engaging in blatant trolling. In the guise of presenting 'technical knowledge' that is not needed on this particular thread, he is derailing the thread, insulting Chinese members, and starting a flame war. Kindly take notice.

 

[The Eagle]

Would be better to stop judging each, debate with knowledge & info available, share your ideas, opinion, analysis or observations & learn; and in-case of conflict agree to disagree with respect and move-on.

Regards,

 

[gambit]

@Deino @The Eagle @WebMaster this guy is engaging in blatant trolling. In the guise of presenting 'technical knowledge' that is not needed on this particular thread, he is derailing the thread, insulting Chinese members, and starting a flame war. Kindly take notice.

How is the information presented in post 593 'not needed'? Determined as 'not needed' by whom or what committee? Can YOU or anyone dispute the information presented?

We have an internet translation of Chinese into English that was essentially gibberish. No fault of anyone. Mr. Fox in post 584 page 39 expressed his difficulty in understanding the technical issues involved via this seriously flawed internet translation.

It took merely 10 min to review every single post in this thread that went back one yr. The bulk of this thread is about the J-20 using a baseless speculative engine by a person looking at distorted images. Most repeated the same line about making a jet engine is difficult but not a single person explained WHY and HOW is it difficult. Interested laymen is bombarded with foreign acronyms with hardly any explanation of what those letters mean and in what context.

For example...Someone mentioned FADEC -- Full Authority Digital Engine Control. Great. If something has 'full authority', does that mean there is 'partial authority'? Has anyone from the Chinese camp made any effort to explain that? Zippo. That is a serious problem on any publicly available forum when it comes to technical issues, that usually, it is rare that someone make efforts to explain things starting from the foundation level and work that thing all the way to final product.

What I presented in post 593, if you already know, leave it alone. The info would be useful to someone else. If you can challenge the info as false, then prove yourself. I gave the interested layman something to stand upon while none of you could.

 

[foxhoundbis]

You are asking for the impossible. .
....
And yet, am willing to bet YOUR understanding of the difficulties of designing a high performance turbine engine, civilian and military, just increased dramatically. From this point on, any claim about the WS-15 must be taken with doubts and hold against what you learned about the turbine engine from publicly available sources.

I studied in a far past mechanical engineering, nowadays I worked as java-analyst developper no one is perfect -french expression -. I understood what U mean, however, objectively I think chinese can afford to overcome these difficulties. Maybe not presently, but in the next future, if not next year, I think they can.
Thx for your accurate explanations.

 

[LKJ86]

WS-15, WS-10, WZ-9...

View attachment 495619
J-20 WS-15

View attachment 495665

 

[Deino]

Please add a short translation or at least summary.