The military-industrial scientific research system of the academic master.

Although there are still some things that they don't understand, since Chang Haonan, the general manager, has made a decision, then what Wei Yongming and Song Jingming have to do next is naturally to execute according to the original plan.

After sending the two away, the former sat back at his desk and stared at the paper on the screen.

In fact, up to now, the problem of computational divergence caused by high computational weights has not been solved, and there is not even a widely accepted explanation for its cause.

It was only through a lot of practice in the past few years that Chang Haonan realized the existence of this problem.

But when he was summarizing the problem to the second point just now, a flash of inspiration suddenly occurred to his mind.

The development of the stress field is mainly affected by the convection term and the deformation term, and evolves rapidly in the form of exponential growth. However, the traditional numerical discretization format based on polynomial interpolation cannot accurately capture the change law of this exponential growth, which makes the contribution of the convection term and the deformation term of the constitutive equation to the stress evolution unable to reach a balance, thus leading to computational divergence.

Therefore, theoretically speaking, as long as the exponential growth rate of stress is slowed down in the area with large stress gradient changes during the solution process of the finite volume method, the stability of the numerical calculation can be guaranteed.

So, after about a quarter of an hour of brainstorming, Chang Haonan suddenly stood up.

The Aviation Power Group Headquarters is a relatively simple administrative agency and does not have research functions.

Therefore, even if you have an idea, you will not get any results just by sitting in front of the computer in the office.

He first picked up the phone and contacted Zhu Yada who was waiting on the first floor.

Then I changed my clothes and went downstairs, ready to take a bus to the new site of the Torch Laboratory which had been completed.

There is a supercomputer there with better performance than the one in Beijing Aviation Computing Center, which is enough for Chang Haonan to test whether his previous idea is correct.

In fact, this work was almost entirely out of Chang Haonan's interest.

Since the TORCH Multiphysics software adopts different theoretical principles and technical routes, it does not face the problem of high calculation weights.

However, as a scholar who studies numerical calculations and regards solving the NS equation problem as a long-term goal, Chang Haonan is not particularly utilitarian in his research in this field.

After all, many seemingly earth-shaking achievements originally originated from some seemingly useless curiosity.

After arriving at the laboratory, he went straight into the computing center located in the basement of Building No. 2...

Inside the computer room, Wang Jie and Qin Haiyang were working on the design and optimization of the engine nacelle for the Falcon Z project.

At this moment, there was a sudden noise at the door.

The two looked up and saw their mentor pushing the door open in a hurry.

"?"

Seeing Chang Haonan suddenly appear, Qin Haiyang, who was not very familiar with the situation of the research group, naturally thought that he was here to check on them.

So he stood up, took out a work log from his schoolbag, sat up straight, and prepared to report on his work progress.

But Wang Jie, who has been studying for a doctorate in the Torch Laboratory for a year, knows very well that Chang Haonan basically would not conduct such formalistic work inspections.

Many supervisors are keen on this because they often ask students to work on research areas that they themselves are not very familiar with, and only through regular reporting can they keep abreast of the project progress.

And here...

Although the Torch Laboratory's business scope is broader than that of most research groups, every research direction must be familiar to the teachers themselves.

Especially Chang Haonan, who basically only needs to take a look at the calculation program and the results, and then ask a few simple questions, and he can almost judge the current situation of the project.

Wang Jie had already deeply experienced this when he was in Shanghai.

Therefore, he first patted Qin Haiyang on the shoulder to signal the latter to relax, and at the same time took two steps forward and briefly explained the work they were currently doing.

Chang Haonan had no intention of checking the work, and Wang Jie's work efficiency and attitude were reassuring, so he simply nodded and sat down in front of another computer terminal next to the computer room, ready to conduct his own research.

However, while waiting for the computer to start up, he inadvertently glanced at the screen next to him.

"Eh?"

It doesn't matter if you don't look at it, but once you look at it, it really attracts his attention:

"You guys are... doing a flow field simulation for the engine nacelle, right?"

Logically speaking, the current optimization of the aircraft's aerodynamic shape has not yet reached the level of detailed design details such as the engine nacelle.

Therefore, this work should be a relatively simple structural optimization problem.

But it is obvious that Wang Jie and Qin Haiyang are not satisfied with this.

"Yes."

Wang Jie scratched his head and replied:

"We have carefully looked at the overall design of the Falcon Z project recently and found that no matter how much we optimize the structure of the engine nacelle, especially the weight, the impact on the performance of the entire aircraft is minimal."

Chang Haonan thought to himself that it was indeed very small, otherwise I wouldn't dare to give it to you two to practice with...

Of course, he couldn't say this out loud, so he pretended to be listening carefully.

"So, we thought, in addition to the structure, whether we can make some optimizations in other places."

"Like aerodynamic drag?"

Looking at the nacelle model that had completed high-precision meshing, Chang Haonan gave Wang Jie a higher evaluation in his heart.

However, the latter shook his head:

"At the beginning, we did think about reducing drag, but the tail-mounted engine layout has an inherent disadvantage in terms of drag, and the optimization range is really small, and it still doesn't help the overall performance too much."

"So in the end, we decided to learn from your previous ideas and use the calculation form of flow field combined with sound field to optimize the cabin, especially the noise level in the rear part of the cabin, by improving the internal structure of the engine nacelle."

It has to be said that although Wang Jie is only in his second year of doctoral studies, he has indeed reached the level of being able to stand on his own.

It's not just a matter of ability, but also of subjective initiative.

At this time, the computer in front of Chang Haonan had already entered the supercomputing system, so he did not continue to ask for other details, and instead devoted himself to his work...

……

The week passed quickly.

Chang Haonan's research has also begun to show results.

He has found a constitutive equation that does not involve diffusion terms, and based on it, he has achieved convergence treatment of convection terms and deformation terms.

It can be said that only the finishing touch is left to solve the problem that is not faced by Torch Group.

But Chang Haonan's doubts did not ease.

Instead, it became even thicker.

You know, he used a lot of special methods to solve this problem.

For example, from a calculation log with divergent results, useful data can be extracted through a data dimensionality reduction algorithm, and then iterations are performed based on this to optimize the form of the constitutive equation.

From a theoretical research perspective, this is a blatant unorthodox and violent cheat.

It is almost like when you are doing multiple-choice geometry questions in the college entrance examination, others are deducing step by step, while you just use a ruler to measure.

however!

It’s not that Chang Haonan is prejudiced against Professor Anthony Jameson.

But this method, probably no one else in the world can master it except him.

Then the problem is coming.

How did COMSOL solve this problem?

Could it be that Professor Jameson has thought of some extremely clever method of calculation that even Chang Haonan himself has not discovered?

Or is it that the former was simply extremely lucky and achieved the same effect as high-order data dimensionality reduction through blind guessing?

It doesn't seem reasonable...

But I can't think of any other possibilities.

In short, Chang Haonan is increasingly looking forward to the day when the new version of COMSOL Multiphysics is officially released.

However, plans cannot keep up with changes.

Before the new product of the competitor was released, something unexpected happened, interrupting Chang Haonan's work schedule...

The trouble comes from the Hudong Factory.

On a rainy Friday afternoon, Lei Zhixing suddenly rushed back to Beijing from Shanghai by train overnight.

"Boss Chang, there is an emergency."

Lei Zhixing took off his wet raincoat and placed it outside the door, then shook off the water droplets on his body before walking into Chang Haonan's office.

As he spoke, the former placed a sealed file bag on the desk.

Unlike the seal they had pasted themselves last time, this time the seal had a big seal on it, indicating that it contained legitimate factory documents.

While Chang Haonan was unpacking the package, Lei Zhixing briefly introduced the situation:

"After Samsung Offshore & Marine won the order for eight LNG ships from us, they acted very quickly and finalized the specific technical plan not long ago."

"Then, we obtained the design draft used by the Koreans for the bid through public channels."

When he said this, Chang Haonan had already taken out the contents of the file bag.

It's a design drawing.

Or strictly speaking, a design plan.

However, a large amount of content was blacked out, resulting in only the design drawing being relatively complete.

But that's enough.

Because almost at the blink of an eye, Chang Haonan saw a familiar structure around the cargo tank...

"I go……"

He was so shocked that his eyes almost popped out:

“Isn’t this our BOG reliquefaction system?”

"How dare you steal?"