"More imaginative?"

Liu Yongquan, who was holding the operation document in his hand, was stunned.

"Ah, I read a MIT paper before, and found that after adjusting the arrangement of the cooling holes into a multi-layer array, although the effectiveness of each row of jets is rapidly attenuated behind the air film holes, due to the mixing of the front row of cooling gas and the mainstream, the ambient temperature of the air film holes in the rear row decreases, so that the effectiveness is gradually increased along the flow direction, and a better wall cooling effect can be achieved."

Chang Haonan stopped what he was doing and looked back at Liu Yongquan:

"You've seen it too, right?"

At this moment, the latter suddenly felt a chill in the back of his neck, and had the feeling of returning to the time when he had just been in graduate school ten years ago and was called over for a group meeting.

PTSD is going to be committed.

Obviously, Chang Haonan is much younger than him, but this tone, this look, this question......

It's exactly like a mentor who can't see a new graduate student.

"I ...... I've seen it. ”

Liu Yongquan wiped the non-existent sweat on Zheng Liang's head, and his brain quickly wondered if he had missed any points before.

But after thinking about it, I still didn't think about it in the end, so I had to continue with trepidation:

"But I remember that the data in that article is actually very problematic, although the author used clever mapping and processing methods to cover up some, but it is obvious that the problem can be seen, his study used a very small scale version of the turbine blade, did not take into account the existence of the amplification effect, but in fact, it is obvious from the data trend that if the blade is enlarged to the level of a normal aircraft turbofan engine, then the cooling effect of the tail end of the blade should not be so optimistic, besides...... Besides, if this research is really meaningful, I'm afraid it will be ...... Also....... ”

"Hmmm......"

Chang Haonan actually heard Liu Yongquan's thoughts completely, but because he was still debugging the equipment with two minds, he couldn't organize a complete language in his mind for the time being, and it happened that what he was going to say later was more complicated, so he had to hum first to show that he heard it.

However, this reaction made Liu Yongquan break out in a cold sweat, and he felt a stronger sense of déjà vu when he returned to graduate school.

"Huh?"

Chang Haonan finally finished the work at hand at this time, wiped the sweat on his palms on the experimental coat, and then turned around and saw Liu Yongquan who looked like a student being trained:

"You want to say that if that research really makes sense, it wouldn't be so easy to send out, right?"

For the most critical core technical details of such a thing, in fact, all countries are similar.

For example, since the concept of air film pore cooling was proposed at the end of the 70s, for nearly 20 years, the entire industry has not been able to find a valuable research article.

Not to mention the roundup.

This led to the development of the turbojet 14 when the research and development of the turbojet 14, due to the high temperature before the turbine and had to be cooled by the air film, the Huaxia Hangfa researchers could only scavenge some scraps from some Russian words, and finally although the turbo of the turbojet 14 was also made, the cooling effect was always somewhat unsatisfactory.

Fortunately, the second-generation domestic nickel-based superalloy was used later, and the most basic reliability and service life were maintained at a certain cost, otherwise Chang Haonan even had to change the turbine in addition to the compressor at that time.

That's not something that can be done in a few months.

"yes."

Hearing Chang Haonan's rhetorical question and his own thoughts, Liu Yongquan finally reluctantly relaxed:

"MIT's article, although there are indeed some breakthroughs in theory, but from the practical application, there is still some distance, from some reports, the main direction of foreign research should be the combination of impact cooling of groove jet and forming hole jet of air film cooling, which may be the reason why this article was finally released."

"That's not right."

Chang Haonan waved his hand directly, and then walked to the side and took off the lab coat on his body.

"This ...... This one...... Mr. Chang, what do I think...... Any questions? ”

Liu Yongquan's heart hung again.

"No, Liu Gong, your idea is fine."

Chang Haonan said and took out an English material from the bag next to him, which was obviously the paper that the two of them had just talked about.

In these years, the number of papers on blade cooling is extremely rare, so any one will be carefully studied in China.

Since online databases are not yet widespread, each research institute even has a dedicated data clerk responsible for collecting content that is actually public.

And the paper in his hand was brought over by the information clerk of the Taihang project team a few days ago.

In fact, Chang Haonan certainly does not need the inspiration of this article, but suddenly from the study of fluid mechanics to the problem of gas-thermal coupling, he always has to find a reason.

He handed the paper to Liu Yongquan:

"It's MIT, they're not right."

"Huh?"

Liu Yongquan, who had just turned the paper to the second page, was immediately stunned.

Not to mention the end of the 90s, even more than 20 years later, MIT is in the science and engineering disciplines, it is still a bit sacred.

Although Liu Yongquan thinks that he is not too superstitious about foreign authorities, he just said that the research in this paper is biased towards the theory of gas-thermal coupling, and has little practical significance for engineering applications.

"Now foreign countries are pinning their hopes on the groove jet, which is nothing more than fancy the weakness of the three-dimensional flow characteristics of the groove jet, and the assumptions of the Sellers superposition model are basically met between the front and rear row jets, so the prediction accuracy of the effectiveness of the adiabatic gas film is higher, and the discrete air film hole has a three-dimensional vortex structure, and the cooling jet of the same exhaust film hole has discrete characteristics, so the multiple exhaust air flows interfere with each other, and there is no way to predict it with the Sellers superposition model...... It's just lazy. ”

Although Chang Haonan had an empty hand, he had basically memorized the details of the article in his mind, and when he said this, he immediately pointed to the paper in Liu Yongquan's hand:

"Take a look at Tables 3-4 through 3-7 of this article."

"Oh......"

Liu Yongquan flipped to the third chapter of the paper in a bit of a hurry.

"If you extract the strength of the vortex structure in a few tables and calculate the Reynolds number, you will find that the turbulent boundary layer can enhance energy transport compared to the laminar boundary layer, thus effectively reducing the strength of the vortex structure. In addition, their research methods, such as using pressure-sensitive paint to measure the effectiveness of the adiabatic air film cooling of the composite angle film of the differential array, and using thermally induced liquid crystal polymers to visually measure the temperature, are indeed quite advanced. ”

After a comprehensive evaluation, Chang Haonan finally concluded:

"Overall, they're actually pretty close to the right direction in this article, but they don't think in that direction when they're processing the data."

"So...... MIT didn't even know that it sent a baby out? ”

Although Liu Yongquan still didn't fully get Chang Haonan's technical ideas, he still understood this part of the content.

"Yes, but they won't be on this wrong route for too long, the problem with the slot jet is too big, and the higher the performance requirements of the aviation engine, the more obvious the defects, and for the Americans, who are already installing and testing the fourth generation engine, it will not take too long to find out."

Chang Haonan walked back to the newly debugged equipment and patted it lightly on the shell:

"Theoretically speaking, the third-generation engine such as turbofan 10 is not practical with such high-end cooling technology, and it is enough to make the third-generation nickel-based blade material and combine it with traditional cooling technology, F110, and AL31F are all doing this."

"But I am still ready to apply multi-row superimposed full-coverage air film cooling on it, and consider the air film cooling effect of the end wall, blade top, trailing edge, and even the side wall of the annular combustion chamber as a whole, so that the cooling effect is better at the same time, and it can also reduce the consumption of cooling airflow, which can be regarded as laying a technical foundation for the fourth and even fifth generation engines in the future."

"...... Fifth-generation engines? ”

If another person said that he wanted to prepare for the fifth-generation engine when the turbofan 10 was not a word, then Liu Yongquan would have to think that the other party was crazy.

But when Chang Haonan said this, he just felt ......

It doesn't seem to be that exaggerated.

(End of chapter)