Chinese Engine Development

Tirdent

Junior Member
Registered Member
Yes, higher T/W ratio due to reduced stage-count is pretty obviously the purpose here. This does sound a bit like a combination of a YF120-like counter-rotating statorless LP turbine with DB 007 style counter-rotating "nested" compressors. That would take a lot of the complexity (e.g. the gearing for counter-rotating drive) out of the DB 007 layout, but is still anything but simple. I would be wary of assuming such an exotic configuration will successfully translate into a production engine.
 

Xizor

Captain
Registered Member
Yes, higher T/W ratio due to reduced stage-count is pretty obviously the purpose here. This does sound a bit like a combination of a YF120-like counter-rotating statorless LP turbine with DB 007 style counter-rotating "nested" compressors. That would take a lot of the complexity (e.g. the gearing for counter-rotating drive) out of the DB 007 layout, but is still anything but simple. I would be wary of assuming such an exotic configuration will successfully translate into a production engine.
The DB 007 seem to have guide vanes. Also, are there any illustrations of the internals ("nested compressors" as you called it) of DB 007?

What I imagine the DB 007 to have had is a rotating "stator casing" - or the entire casing rotating using a planetary gear connected to the rotor shaft.
 

Xizor

Captain
Registered Member
Horobeyo:
The final form + the first modification at this stage, there are two types: WS-20 + Oil 20, WS-15 + F-20 two-seater



Quadro30Mbps :

In fact, this year’s aviation industry really surprised me. I expected it, unexpectedly. I didn’t expect the serialization project to develop so fast, so I directly combined the final form with the current stage. The modification is integrated ●, the thing that may be delayed is to wait to see the final form.



Screenshot_20211201-225704.jpg

Reply to @探月球: That lamp is really fascinating. The hard tube technology is only verified on a certain platform, and the Y20 of the two engines has no hard tube, and there is no hard tube oil port on any model, so install it first. I can’t figure out the meaning of a lamp

 

taxiya

Brigadier
Registered Member
For people who is interested in this new engine design, here is the research paper of the person.
多级无导叶对转涡轮气动设计研究 / Aerodynamic Design of Multistage Vaneless Counter-Rotating Turbines
1638385916150.png

Paper was published in 2014. This engine apparently is the prototype out of this research.

Here is the scheme of the counter-rotating turbines. Blade set R1 is connected to an outer wall/casing which connects to the inner shaft through spokes. This kind of arrangement can expand to multiple turbine stages.

1638386017649.png

The paper acknowledges all existing counter-rotating turbine works, but is trying to address their short-coming that are mentioned here by some members here.

The report IMO is sentimental and a bit exaggerating, such as this paragraph using phrases "Innovative theory" and "revolutionary new type of engine"

徐建中常年从事航空发动机研究,本世纪初他敏锐地发现,航空发动机发展到四代机之后,靠叶片折转提高压比的办法走到了尽头。他另辟蹊径,把目光放到了对转气动布局上,通过创新增压原理,提出一种颠覆性新型发动机——采用对转大大减少压气机和涡轮级数,提高了推重比。

Zhao Wei's solution is innovative, but it is based on existing principle and can not be said as revolutionary.

In China this kind of report would be called "八股文", formulated propaganda article, it is a tradition of hundreds of years. It often hides very useful information but need careful deciphering by removing the over and under statements.
 

Xizor

Captain
Registered Member
For people who is interested in this new engine design, here is the research paper of the person.
多级无导叶对转涡轮气动设计研究 / Aerodynamic Design of Multistage Vaneless Counter-Rotating Turbines
View attachment 79574

Paper was published in 2014. This engine apparently is the prototype out of this research.

Here is the scheme of the counter-rotating turbines. Blade set R1 is connected to an outer wall/casing which connects to the inner shaft through spokes. This kind of arrangement can expand to multiple turbine stages.

View attachment 79575

The paper acknowledges all existing counter-rotating turbine works, but is trying to address their short-coming that are mentioned here by some members here.

The report IMO is sentimental and a bit exaggerating, such as this paragraph using phrases "Innovative theory" and "revolutionary new type of engine"

徐建中常年从事航空发动机研究,本世纪初他敏锐地发现,航空发动机发展到四代机之后,靠叶片折转提高压比的办法走到了尽头。他另辟蹊径,把目光放到了对转气动布局上,通过创新增压原理,提出一种颠覆性新型发动机——采用对转大大减少压气机和涡轮级数,提高了推重比。

Zhao Wei's solution is innovative, but it is based on existing principle and can not be said as revolutionary.

In China this kind of report would be called "八股文", formulated propaganda article, it is a tradition of hundreds of years. It often hides very useful information but need careful deciphering by removing the over and under statements.

It's a relief. The other option was to individually gear the stages and that means impractical and overengineered mess fit for museums.

But on the exaggeration part ... I really don't think it's an exaggeration if they manage to bring the performance upto modern engine standards and beyond. We really don't have any existing engines of this kind and its impressive to see a technology demonstrator that enquiries into this method. Not at all a downer. Its good news, at least from R&D perspective.
 

taxiya

Brigadier
Registered Member
It's a relief. The other option was to individually gear the stages and that means impractical and overengineered mess fit for museums.

But on the exaggeration part ... I really don't think it's an exaggeration if they manage to bring the performance upto modern engine standards and beyond. We really don't have any existing engines of this kind and its impressive to see a technology demonstrator that enquiries into this method. Not at all a downer. Its good news, at least from R&D perspective.
I agree with you. Innovative is a very relative and subjective term. An good idea worth nothing if it can never be realized in practical terms. If his path leads to common application, he would be innovative than any other "failed" efforts.
 

latenlazy

Brigadier
For people who is interested in this new engine design, here is the research paper of the person.
多级无导叶对转涡轮气动设计研究 / Aerodynamic Design of Multistage Vaneless Counter-Rotating Turbines
View attachment 79574

Paper was published in 2014. This engine apparently is the prototype out of this research.

Here is the scheme of the counter-rotating turbines. Blade set R1 is connected to an outer wall/casing which connects to the inner shaft through spokes. This kind of arrangement can expand to multiple turbine stages.

View attachment 79575

The paper acknowledges all existing counter-rotating turbine works, but is trying to address their short-coming that are mentioned here by some members here.

The report IMO is sentimental and a bit exaggerating, such as this paragraph using phrases "Innovative theory" and "revolutionary new type of engine"

徐建中常年从事航空发动机研究,本世纪初他敏锐地发现,航空发动机发展到四代机之后,靠叶片折转提高压比的办法走到了尽头。他另辟蹊径,把目光放到了对转气动布局上,通过创新增压原理,提出一种颠覆性新型发动机——采用对转大大减少压气机和涡轮级数,提高了推重比。

Zhao Wei's solution is innovative, but it is based on existing principle and can not be said as revolutionary.

In China this kind of report would be called "八股文", formulated propaganda article, it is a tradition of hundreds of years. It often hides very useful information but need careful deciphering by removing the over and under statements.
Nice find! And here I thought I was going to have to spend some time looking up and thinking about terms from the story to try to figure out what was going on with the demonstrator.
 

latenlazy

Brigadier
I agree with you. Innovative is a very relative and subjective term. An good idea worth nothing if it can never be realized in practical terms. If his path leads to common application, he would be innovative than any other "failed" efforts.
It's a relief. The other option was to individually gear the stages and that means impractical and overengineered mess fit for museums.

But on the exaggeration part ... I really don't think it's an exaggeration if they manage to bring the performance upto modern engine standards and beyond. We really don't have any existing engines of this kind and its impressive to see a technology demonstrator that enquiries into this method. Not at all a downer. Its good news, at least from R&D perspective.
Guys I think you’re burying the headline. This design apparently gets a pressure ratio of *10* with *4* stages. For reference the F119 has PR of 6 with 6 stages, the EJ-200 gets 6 with 5 stages, and Idz. 30 apparently gets 6.5 with 5 stage.
 
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