When Chang Haonan said this, he deliberately paused.

Obviously, not everyone immediately accepts the concept from a theoretical perspective.

But he had already thought of it.

"The report made by Comrade Liu Yongquan just now talked about the modeling design method of the compressor bending Ye Shan, and I happen to have an example here."

Chang Haonan released the next PPT, which is a large aspect ratio blade with an extremely complex shape.

"You can join me in experiencing the design process of this 'ultra-high load adsorption bending joint leading edge edge blade'."

This name directly made many people laugh.

As we all know, the longer the name, the stronger the strength.

However, at this time in the late 90s, the domestic atmosphere had not yet been damaged by Europe and the United States, and this kind of name with a series of adjectives was not very common.

And some keen people will find that Chang Haonan also marked several adjectives in front of the leaves with different colors, which seems to be intentionally emphasizing this point.

Sure enough, he went on to explain:

"Notice that there are several elements that need to be considered in the design process and that will affect each other."

"High load means that the single-stage boost ratio is high, and the efficiency of the blade shape itself must be sufficient; Adsorption type, indicating that the multi-slit adsorption blade type that controls the separation of the attached surface layer of the blade is applied. Bending and sweeping combination, which shows that the bending and sweeping design is applied at the same time, and the blade is an asymmetrical complex shape in three-dimensional space. The last leading edge strip means that we have also considered the adverse effect of the endwall effect on the efficiency of the compressor blades, and we want to minimize this effect as much as possible. ”

The smile I had just now was gone.

When it comes to design, the more constraints there are, the more difficult it is.

And this "ultra-high load adsorption bending and sweeping joint leading edge edge blade" is obviously the type of buff full.

Generally, when encountering this situation, these design elements are optimized separately, and finally combined and then put on the bench for actual machine testing, and fine-tuning the parameters a little bit.

This kind of play that needs to be considered at the same time in the paper design stage is definitely a game that I didn't dare to think of before.

But everyone's smile did not disappear, but it was transferred to Chang Haonan's face:

"It's a little more complicated, but as an example, it's certainly typical enough."

"So let's take it step by step, first of all, give a simplest curved leaf Shan shape......"

“……”

With the help of examples, most of the researchers who were engineers finally understood the new method proposed by Chang Haonan.

It started out as one-dimensional, then as two-dimensional, and then as quasi-three-dimensional......

Now it's called full three-dimensional, which sounds like a natural fit.

But after all, all of you are professionals, and you will realize almost immediately that the impact of this new theory on the field of aero-engine design is by no means as mundane as its name suggests.

It is no exaggeration to say that if all the cakes just painted by Chang Haonan can be realized, then the workload of the aero-engine compressor design process may drop by an order of magnitude!

Considering that most of the reductions in the middle are actual machine tests, the time, funds and reduced risks saved by this round and forth can almost cross the "quantitative change" and enter the category of "qualitative change".

In the past, aero engine design was a highly experienced and heavily tested undertaking, largely because the losses due to viscous effects accounted for a large proportion of the total losses, which had a direct impact on the energy build-up, clogging and surge margins of the blades.

However, the quasi-three-dimensional design method considering the S1/S2 flow surface is highly dependent on statistical means (i.e., guessing first and then iterating) for the calculation of viscous effects, and even the cutting-edge streamline curvature method developed by General Electric and Rolls-Royce still requires a huge amount of experimental data to numerically fit the diffuser loss, shock loss, gap loss, end wall loss, backward angle and blockage estimation, etc., which often takes several years or even more than ten years......

Note that this is only the compressor part of the three major parts of the aviation engine, and does not consider the two hot end parts of the combustion chamber and the turbine and the coordination of the three.

In general, with the current technical means, it is not unusual to design a new engine from scratch without a core engine or an old model as a base, and it will not take 15-20 years.

In fact, it took about 15 years for the turbofan 10 on the original timeline to go from instability to maturity.

However, if the specific situation of the three-dimensional viscous flow can be directly given by numerical calculation, then the entire compressor design process can be completed in about 2-4 years, even with a conservative estimate.

Of course, the premise of all this is that the manufacturing level is up to standard, and the things on the design drawings can be produced originally.

It's just that at present, Huaxia's aviation development industry is full of shortcomings, so it must be strengthened from the beginning, that is, in the design stage.

The reason why the TORCH Multiphysics software designed by Chang Haonan emphasized the priority of ensuring the progress of the mechanical-thermal coupling module from the very beginning is to expand its business in the field of material processing, especially in the field of thermal processing of metal materials.

This is also an indispensable technology in the development of high-performance aero engine hot-end components.

Huaxia's backwardness in the field of materials is often not that it cannot make the raw materials themselves, but that the products made with the same raw materials do not meet the requirements.

In contrast to compressors, which are cold-end components, the focus of research on hot-end components, especially turbines, is basically on how to withstand the highest possible temperatures.

Generally speaking, increasing the pre-turbine temperature can directly increase the gas flow rate, and will not directly affect fuel consumption, is the simplest and crude, but also the most intuitive and effective means of increasing the thrust - provided that the overall design level can be correspondingly up to the standard, otherwise a high pre-turbine temperature does not mean high performance, the typical negative teaching material in this regard is the later Japanese XF6-1, just look at the 1600 °C vortex temperature has been on an equal footing with the fourth-generation turbofan engine, but the actual level is about the same as a reduced version of RD33......

The minimum pre-turbine temperature of the third-generation (fourth-generation foreign standard) turbofan engine cannot be lower than 1200 °C, and if you want to achieve the index set by Chang Haonan for the turbofan 10 in his heart, then this number will probably be increased to more than 1400 °C.

Obviously, there is no material that can rely on its properties to work stably at such high temperatures for long periods of time, so this requires some other ingenuity to help.

TORCH Multiphysics has the potential to solve this problem.

But that's not the focus of today.

Therefore, regarding the research and development of hot-end components, Chang Haonan only briefly talked about it in the final prospect part.

No matter how good he is, it is impossible to introduce all the key technologies about the third-generation turbofan engine in half an afternoon.

In fact, even this new approach to compressor design is only a matter of throwing out the concept and explaining it briefly.

But it's enough.

Looking at the eyes of nearly 200 people in the venue, Chang Haonan knew that his mobilization was quite successful.

That's right, although he has been talking about technology on the surface, but he is not just talking about technology.

It's more about faith.

Although the design and production of turbojet 14 has been completed, and even the order has exploded to the 410 factory to give a part of the 460 factory in Guizhou Province to relieve the pressure, at least before today, everyone has no bottom about the matter of "whether the turbofan 10 can be made next".

For aviation power powers such as the United States and the Soviet Union (Russia), this kind of thing will not be a problem at all.

Now that the previous generation has been completed, it is basically logical to continue to develop the next generation.

However, in China, due to the fact that aviation power cannot be independently established for a long time in the past, there is often no technical relationship between various types of aero engines, and each new model is almost from scratch.

This was also the case between Turbojet 14 and Turbofan 10.

After being deeply improved by Chang Haonan, the former has of course applied a lot of new technologies, but after all, only a very small number of people know this detail.

It's normal for most people to have concerns.

But to do projects, especially this kind of project to concentrate forces, the most taboo is that people are not aligned, looking forward to the future.

Therefore, Chang Haonan's report today is to give a clear answer - turbofan 10, which can definitely be done!

So, after talking about the technical aspects, he changed his mind:

"From the example just now, you comrades should be able to see that even if new design theories and design tools are applied, the research and development of the third-generation turbofan engine is still a very large task, and it is difficult to rely on the strength of only one or two units to complete."

"So, in this matter, I think it should be carried out in the form of multi-agency joint research and development."

Chang Haonan's voice fell, and a whisper suddenly sounded in the venue.

Although he said "I think", anyone with a discerning eye can see that it is definitely not the opinion of one or two people to be able to give such a clear statement on such an occasion.

At the very least, the Commission of Science, Technology and Industry for National Defense has nodded its head, and even has obtained a higher-level license.

But the question is, how to unite?

(End of chapter)