The Military-industrial Scientific Research System of the Academic Master Chapter 395

Chapter 395 A new design method for turbofan 10

Half an hour later, accompanied by soft entrance music, the first China Aerospace Engine Industry Conference officially opened.

Chang Haonan, who could only sit in the back row during such meetings in the past, as the most important guest and organizer of the meeting, was naturally invited to the middle position in the first row.

Sitting with Liu Zhenxiang, who was also specially invited.

Originally, the conference affairs department planned to arrange for him to give the first report immediately after his speech, but Chang Haonan said that the content he prepared was too long and too formal, and it was best to put it in the finale.

This can also maintain the participants' sense of expectation to a certain extent.

He has read the reports prepared by several other people before. In terms of the current development level of China's aviation power field, they can be considered to be of a very high level. Many of the conclusions were only achieved after the 21st century in previous lives.

Although these are breakthroughs in very specific directions, so they are not a leap forward, they can definitely inspire researchers in other fields in terms of research ideas and methods.

And if Chang Haonan had thrown out his heavy content first, then probably not many people would care about the following things -

Always leave some opportunities for others.

Therefore, after briefly summarizing the achievements in the aero-engine field over the past year, Chang Haonan generously gave the first official opportunity to the academician Liu Zhenxiang next to him.

Although the latter is also a Taishan Beidou-level figure in the industry, the main content of his report is about the Chinese aerospace engine industry standards that are currently being formulated, especially the relevant standards in plateau environments of 3,000 meters and above. Following several reports There is not much overlap in content.

"Due to China's special geographical and terrain conditions, a considerable number of airports in key directions are built on plateaus and high plateau areas. This is a situation that almost no other country has ever faced. Therefore, a plateau condition standard that meets the requirements of our national conditions is important for It will undoubtedly be of great significance to my country's national defense security and the flight safety of the civil aviation industry..."

As Liu Zhenxiang's report came to an end, Chang Haonan also lowered his head, preparing to sort out the key points he had just written down.

But at this moment, he suddenly heard his name.

“At the end, I would like to express my special thanks to Comrade Chang Haonan.”

Chang Haonan raised his head almost subconsciously, and then found Liu Zhenxiang behind the podium staring at him with a smile.

"If he had not submitted a key technical document to his superiors at the critical moment of high-altitude bench testing of the turbojet 14 engine, I am afraid that the entire aviation industry standard content we see today would not have appeared. From this, A series of new projects and new models will undoubtedly not exist. ”

As soon as these words came out, the whole place was in an uproar.

The extensive revision of aviation-related clauses in the national military standards has been something that has been making a lot of noise since the second half of last year. It is also closely related to the projects of almost everyone here. Naturally, no one does not know about it.

However, not many people know the specific details.

Everyone only knows that the whole thing started when the aero-engine quality acceptance standard GJB/Z64-94 was suddenly modified into a brand new GJB/Z64-97A.

This is definitely something everyone expects. After all, the original set of standards copied from the Americans are completely unsuitable and lack operability. Not to mention passing the test more than two years after its release, no one can even explain how the test should be carried out. .

Now it's a new set of standards that, although not nearly as stringent, makes you want to know which screws to turn and how many times to turn them during the test, which is naturally very satisfying.

But before today, not many people knew that the core content of GJB/Z64-97A was almost completed by Chang Haonan alone.

A few seconds later, the entire venue finally came to its senses and began to give Chang Haonan thunderous applause.

Now that the situation has reached this point, the latter has no choice but to stand up, turn around and gesture slightly to the back.

However, Liu Zhenxiang seemed to have made a bad start.

The content of the report at this aviation industry conference is actually more or less related to Chang Haonan.

Now that even Academician Liu expresses his gratitude, why don't other people express his gratitude?

So everyone has to say a sentence or a rainbow fart at the end of the report.

Chang Haonan had already read all the reports, so his original plan was to sneak out to rest after Liu Zhenxiang finished speaking, and then return to the venue when it was his turn.

As a result, all the eyes of the audience would focus on him every once in a while, and there was no chance at all.

Due to standard conversion, even if the old standard is not implemented at all, the conversion only involves paper content is a very complicated matter, so Liu Zhenxiang distributed a lot of less important content in the form of vertical topics to some people with sufficient confidentiality levels. Project Team.

Although the funding is not large, it is almost a life-saving straw for many people.

And many people here today have benefited from this.

It is no exaggeration to say that Chang Haonan can be regarded as half of their parents.

Therefore, even during lunch and breaks between meetings, waves of people came to the front to express their gratitude or admiration to Chang Haonan...

When the meeting process finally progressed to Chang Haonan taking the stage, he even felt a little relaxed.

The applause lasted longer than the previous times.

Chang Haonan stretched out his hands and pressed down, and then the whole place fell silent again.

“Comrades, what I want to talk about today is more formal.”

Chang Haonan said as he clicked on the first page of his PPT and projected it on the screen:

“Full three-dimensional design and unsteady analysis method of the third-generation high-thrust turbofan engine”

The moment this title appeared, the entire venue fell silent.

What followed was the sound of notebooks being opened almost in unison.

We are all industry insiders, and everyone knows what the description "third-generation high-thrust turbofan engine" refers to.

You must know that the successful finalization of a second-generation turbojet engine last year injected a huge amount of funds and vitality into the field of aviation power that was unimaginable in the past.

Now this is obviously about moving the Turbofan 10 from the pre-research stage to a real project.

If you can participate in it, it will be immeasurable whether it is an improvement in your ability, resume or network.

So everyone immediately got into high spirits.

Seeing that everyone was ready, Chang Haonan officially started his report:

“The previous speakers today have introduced in great detail some of the most cutting-edge research in the field of aviation engines in our country. I am very happy to see that after the successful completion of the design and production of the turbojet 14, our aviation engine research has It did not stay where it was, but was pushed further to new heights by you..."

After confirming his previous work, he changed the subject and went directly to the topic:

“But comrades, this alone is not enough.”

"Everyone must have known to some extent that our two domestically produced third-generation fighter jets, the medium-sized Project 10 and the heavy-duty Project 11, are in the process of being smoothly advanced. In fact, if it were not for the recent weather, , and may even have completed its first flight.”

"But these two aircraft still use AL31F engines imported from Russia in terms of aviation power. Of course, judging from the current situation, the Russians will not cut off engine supply to us like the Americans. So in a short period of time, you don't have to worry about the neck being stuck.”

"However, those of us engaged in aviation have learned too many historical lessons. In the final analysis, it is better to have our own parents than to have our own parents. Whether it is from the perspective of saving foreign exchange for the country or from the perspective of ensuring the independent development of national defense capabilities, we need to develop A new type of aviation power sufficient for third-generation fighter aircraft is coming!”

"Of course, to be fair, with the technology we have now, if we want to create a turbofan with a thrust ratio of more than 8, there will be problems almost everywhere from design to manufacturing, but I think it doesn't matter. It will be difficult to pass. All difficulties are overcome step by step, and what I want to focus on today is also the starting point for developing a new model of aeroengine, which is a new design theory! "

Speaking of this, Chang Haonan clicked the mouse again, and a formula familiar to everyone appeared on the screen.

N-S equation.

"As we all know, the N-S equation is the most universal differential equation in fluid mechanics calculations, and it is also the basic physical model for studying the internal flow mechanism of a compressor. However, it is limited by the lag in the development of related research technologies and people's imperfect understanding of the flow mechanism. nature, corresponding to engineering requirements, this equation needs to be simplified, and a series of design methods and theories have been derived from this.”

"Before the aerodynamic theory of impeller machinery was formally formed, the aerodynamic design of impellers always adopted the one-dimensional flow method. However, this has little to do with the topic we are going to talk about today. Because the simplification is too serious, there is almost no engineering practice. value."

“The design theory we are currently using is the S1/S2 flow surface quasi-three-dimensional analysis and design theory based on two assumptions of steady state and partial consideration of viscosity effects. It transforms the three-dimensional flow solution problem of the compressor into two two-dimensional iterations. This theory simplifies the flow from the blade root to the blade tip in the compressor channel as the flow on a certain S2 flow surface, and at the same time simplifies the flow between the blades as the flow on a certain S1 flow surface, and passes through the two The mutual iteration between similar flow fields is used to obtain the entire three-dimensional flow field solution. So far, this is also the mainstream design method used in developed countries in Europe and the United States.”

“Originally, this should be the most advanced theory we can use.”

Chang Haonan showed a smile and lightly tapped the podium in front of him:

“But I was lucky. A few months ago, I accidentally discovered a new method for dimensionality reduction of nonlinear partial differential equations.”

The originally solemn atmosphere suddenly became a lot more relaxed, and there was a burst of laughter below.

Everyone knows that this kind of thing cannot be accomplished entirely by luck.

Just because Chang Haonan is willing to be so humble, naturally no one can point it out.

“This new method of numerically solving partial differential equations, combined with the multi-physics simulation modeling software that I recently took the lead in developing, especially the new grid generation technology, provides us with a brand new possibility.”

The software interface of TORCHMultiphysics is slowly displayed on the screen.

"Introducing a complete viscosity simulation calculation into the design system, the flow field structure can be analyzed and evaluated based on the calculation results, and improvement measures can be proposed in a timely manner. This method can not only more accurately ensure that the designed compressor has higher efficiency and The wider surge margin can also reduce the number of iterations in each design stage, reduce the reliance on research test components during the research process, and can even directly enter the entire compressor test. "

“Following the rules of several past methods, I named this theory—full three-dimensional design and flow analysis!”

(End of this chapter)

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