Chinese Engine Development

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Tirdent

Junior Member
Registered Member
latenlazy said:
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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Not so fast. On the other engines you mention these pressure ratios refer to the *compressor*, whereas this paper apparently concerns itself with *turbines* exclusively! If you want to take an efficiency penalty (mind you, turbine stage efficiencies are routinely around 90% or greater), turbine pressure ratios can exceed 4.0 in a single stage.

Perhaps the demonstrator engine also has DB 007 style counter-rotating compressors (which can be expected to give higher pressure ratio per blade row pair), but the paper does not apply to that aspect. As for schematics of that engine, this is probably your best online source:
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Unfortunately they aren't particularly intuitive to interpret, as some of the other eccentricities of the design (including the wacky partial admission turbine cooling system) add to the complexity.
 
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latenlazy

Brigadier
Tirdent said:
Not so fast. On the other engines you mention these pressure ratios refer to the *compressor*, whereas this paper apparently concerns itself with *turbines* exclusively! If you want to take an efficiency penalty (mind you, turbine stage efficiencies are routinely around 90% or greater), turbine pressure ratios can exceed 4.0 in a single stage.

Perhaps the demonstrator engine also has DB 007 style counter-rotating compressors (which can be expected to give higher pressure ratio per blade row pair), but the paper does not apply to that aspect. As for schematics of that engine, this is probably your best online source:
Please, Log in or Register to view URLs content!


Unfortunately they aren't particularly intuitive to interpret, as some of the other eccentricities of the design (including the wacky partial admission turbine cooling system) add to the complexity.
Click to expand...
@taxiya Do you have the full paper? I kind of want to see if they're referring to "turbine" in general terms (as in the class of the machinery) or specifically with regard to the turbine section of an engine. My guess is actually the former, and the simulation they ran is generic to any rotating turbo compression mechanism and is not specific to the turbine section of an engine.

My thinking here is that the paper specifically makes mention of developing past 4th generation engines, but if military turbofans are implicitly the focus of this research, a 4 stage turbine section makes very little sense for such an application, so the utility of this counter-rotating design seems very limited for that scenario.
 
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broadsword

broadsword

Brigadier
taxiya said:
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.
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I would call it evolutionary. Nice that it could produce a higher thrust-to-weight ratio than the F135.
 
Xizor

Xizor

Captain
Registered Member
Do we have any images of WS18 ? What primary source says it is related to D30KP2 specifically
I know China never got access to Burlak D30KP3. Maybe China was miffed at it and wanted WS18 to be as good as D30KP3. Since D30KP3 has twisted fans, maybe WS18 (or its next variants) may have it.
 
T

taxiya

Brigadier
Registered Member
latenlazy said:
@taxiya Do you have the full paper? I kind of want to see if they're referring to "turbine" in general terms (as in the class of the machinery) or specifically with regard to the turbine section of an engine. My guess is actually the former, and the simulation they ran is generic to any rotating turbo compression mechanism and is not specific to the turbine section of an engine.

My thinking here is that the paper specifically makes mention of developing past 4th generation engines, but if military turbofans are implicitly the focus of this research, a 4 stage turbine section makes very little sense for such an application, so the utility of this counter-rotating design seems very limited for that scenario.
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It was available a month ago on Baidu Wenku here
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. Now it is removed. I saved a copy in picture format. But it seems that it is downgraded to much lower resolution after uploading to sinodefenceforum (I have tried once).
 
Xizor

Xizor

Captain
Registered Member
Temstar said:
I think that really shiny WS-10 TVC is a display piece and not the real deal. There were discussions about it on this site before. The photos of the actual J-10 TVC demonstrator has some differences to this engine:
View attachment 79972
Note the black and white colouration inside the petals
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Very helpful.
Although i do recollect that discussion (esp now that you mention it) , I posted this because I thought it is a better image. To be frank, I am sure the same image had been uploaded long ago. Since I found it in weibo in a recent post, i wasn't taking any chances.
 
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