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.
In the past, Chang Haonan, who could only sit in the back row during such meetings, was naturally invited to the middle position in the first row as the most important guest and meeting organizer this time.
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 expectations of attendees 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 in the 21st century in previous lives. The results were achieved later.
Although they are all breakthroughs in very specific directions, so they are not a leap forward, but in terms of research ideas and research methods, they can definitely produce results for researchers in other fields. Inspire.
And if Chang Haonan throws out his heavy content first, then I am afraid that few people will care about the following things——
Always give it to others Leave some opportunities.
Therefore, after briefly summarizing the achievements in the field of aerospace engines 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. , there is not much overlap in content with the following reporters.
“Due to China’s special geographical and terrain conditions, a considerable number of airports in key directions are built in plateau and high plateau areas. This is a situation that almost no other country has faced. Therefore, an airport that meets the requirements of our national conditions The plateau condition standards 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 Hao Nan also lowered his head, preparing to sort out the key points he had just memorized.
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 we see today would not have emerged. The standard content, and the series of new projects and new models derived from it, will undoubtedly not exist."
As soon as this was said, there was an uproar.
The large-scale revision of the aviation-related clauses in the national military standards has been a matter of great turmoil since the second half of last year. It is also closely related to the projects of almost everyone here. Naturally, it is impossible for anyone to 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 that everyone expects. After all, the original set of standards copied from the Americans were completely unsuitable and lacked operability. It has been more than two years since its release, let alone passed the test. No one can even say that it has passed the test. Understand exactly how to conduct testing.
Now it is replaced by a new standard that although the strictness is similar, but it can even tell you which screws to turn and how many turns 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.
After a few seconds, the entire venue finally reacted 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, do other people have a reason to mention it specifically?
So everyone has to say a sentence or a rainbow fart at the end of the report.
Because Chang Haonan had read all the report contents a long time ago, 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, the eyes of the whole audience would be focused 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 that 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 Some project teams with sufficient confidentiality levels were given.
Although the funding is not much, 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, clicking on the first page of his PPT and projecting it onto the curtain:
"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.
Everyone is an industry insider, and everyone knows exactly what the description "third-generation high-thrust turbofan engine" refers to.
You know, 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 to transfer 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 connections.
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 the latest developments in the field of aviation engines in our country. Regarding some cutting-edge research situations, I am very happy to see that after the successful completion of the design and production of the turbojet 14, our aerospace research did not stay where it was, but was pushed to a new level 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 is more or less sure. As you all know, our two domestic 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, they might even have been completed. "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 should not be like this. The Americans are also cutting off the supply of engines to us, so we don’t have to worry about the neck being stuck in the short term.”
“But we aviation people have learned too many historical lessons. It is better to have what your father has than to have what you have. Whether it is from the perspective of saving foreign exchange for the country or ensuring the independent development of national defense capabilities, we need to develop a new type of aviation power that is sufficient for third-generation fighter jets.”
"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! ”
said! Here, Chang Haonan clicked the mouse again, and a formula familiar to everyone appeared on the curtain.
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 understanding of the flow mechanism inside the compressor. The imperfect understanding of the flow mechanism requires the simplification of this equation, which has led to a series of design methods and theories. "
"There is no formal aerodynamic thermodynamics theory for turbine machinery. Before its formation, the aerodynamic design of impellers had always adopted a one-dimensional flow method, but this has little to do with the topic we are going to talk about today. Because the simplification is too serious, it has almost no value in engineering practice. ”
“The design theory we are currently using is the S1/S2 flow surface quasi-three-dimensional analysis and design theory based on the 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 Iterate between the similar flow fields 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 what we can do. The most advanced theory used."
Chang Haonan smiled and tapped the podium in front of him:
"But I was lucky. A few months ago, I accidentally A new dimensionality reduction method for nonlinear partial differential equations was discovered.”
The originally solemn atmosphere suddenly became a lot more relaxed, and there was a burst of laughter.
Everyone knows that this kind of thing cannot be accomplished entirely by luck.
But Chang Haonan is willing to be so humble, so 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 A new possibility.”
The software interface of TORCHMultiphysics was 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 With higher efficiency and wider surge margin, it 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)