Chapter 828 Isn’t it just equipment? Buy it!
Geological exploration is by no means an easy and pleasant task, even when precise coordinates have been obtained.
Fortunately, today's technical equipment, especially vehicles and helicopters, are relatively complete, and safety is relatively guaranteed.
But if you really want to dig deeper into a point, it will still take anywhere from a few months to a few years.
Therefore, after deploying some key points of the exploration work, Chang Haonan and Meng Zhenyuan returned to Beijing Hang University.
For them, all they can do now is wait.
Fortunately, Chang Haonan has no shortage of projects at hand.
In the next half month, in addition to paying daily attention to the progress of Ritchie flow surgery, he also guided Li Yabo on his graduation project.
Actually, Chang Haonan didn’t know what the so-called “1-meter all-composite shell” specifically meant until the graduation project before the Spring Festival——
Hao Fei The company wants to develop a new engine nacelle for the C808 passenger aircraft, which is about to be put into mass production.
It's the thing that fixes the engine to the fuselage.
The diameter is about 1.3 meters.
If successful, it can probably reduce the weight of the aircraft by about 300kg.
It can only be said that technically the future is promising.
But there is nothing operable for the time being.
At present, almost all high-grade composite materials used in China rely on imports, and the cost is very high.
The weight saved by replacing titanium-aluminum alloy with carbon fiber, even if it is extended to the full life cycle, is not worth the extra cost in the manufacturing process.
Of course, there’s nothing wrong with doing some research in advance.
After all, there will be many places where similar designs will be used in the future.
In the long run, the working environment of the casings of launch vehicles and ballistic missiles, the bodies of large aircraft, and even the fan blades and casings of turbofan engines are not particularly harsh and the probability of damage is relatively low. Parts, replacing traditional alloys with carbon-based composite materials is a major trend.
Think of it as a technical reserve.
Of course, for an undergraduate doing graduate work, these are still relatively far away.
So Chang Haonan’s requirement for Li Yabo is to design a theoretically feasible overall plan.
The main purpose is to exercise the latter's ability to use existing tools to solve problems.
Otherwise, if the students of the creator of TORCMultiphysics cannot play the software developed by their teacher, it would be really embarrassing to tell them.
However, life is like this sometimes.
When you don’t expect something, it can often give an unexpected result.
……
One day at the end of March, just as Chang Haonan was replying to Professor Perelman’s email asking about the progress, Li Yabo suddenly poked his head into the office:
"Teacher, please take a look, my simulation results seem a bit strange..."
These days, students with laptops are naturally rare, so Chang Haonan could only follow Li Yabo to the student office to check on the situation.
It is said to be a student office, but now there are fewer students than teachers in the Torch Laboratory, so it is actually equivalent to Li Yabo having it all to himself.
So, the young man simply moved his luggage from the dormitory and started his life as 007 the Liver Emperor.
After entering the door, Chang Haonan carefully bypassed a folding bed and came to Li Yabo's workstation.
On the computer screen, a finite element model that is thick in the middle and thin at the ends, slightly cigar-shaped, is displayed.
It was he who designed the overall engine nacelle scheme.
Chang Haonan came closer to the screen and quickly read the results of the finite element calculation——
In 1999, last year, a hardware engineer named Huang Renxun officially created the "GPU" "This term.
In fact, the processor that assists the CPU in graphics processing took shape as early as the 1980s.
But the GeForce256 launched by NVIDIA has brought an epoch-making feature.
Real-time programmable shading technology.
TORCHMultiphysics will soon launch a free (not free shipping and storage carrier materials fee) and optional feature update.
When the user's computer is equipped with an independent GPU, the results of finite element calculations can be directly superimposed on the surface of the 3D model in the form of graphic rendering.
Instead of just outputting a dry form like in the past.
Although in terms of results, there is no difference between the two.
But for the human eye, the former method is obviously much more intuitive.
Therefore, Chang Haonan can almost see at a glance that the design on Li Yabo's computer basically meets the project requirements proposed by Haofei.
"The result seems to be okay..."
He stood up straight again:
"Do you think there is something strange?"
At this time, Chang Haonan glanced at the annotation in the lower right corner of the screen from the corner of his eye.
The properties of the material he chose are written there.
Young's modulus is 700Gpa...
The corners of his mouth twitched hard.
No need to look at other parameters.
Definitely T700 carbon fiber.
It can only be said that if you are not a family member, you don’t know how expensive firewood and rice are. The T700 has only been put into commercial use in the past two years, and because the production capacity has not increased, the unit price is quite high.
If this kind of thing is used extensively on a small 50-ton regional aircraft, I am afraid that the user will kill it...
Fortunately, it is still in place In the design stage, judging from the standards of practice anyway, the problem is not big.
"This is it."
Li Yabo said, zooming in and out of the 3D model.
Finally, Chang Haonan discovered that the carbon fiber structure on the screen was not just a shell modeled.
It is composed of many thin layers.
“Have you studied the impact of composite laminate structures on performance?”
Chang Haonan was a little surprised.
“Yes, I think if we just provide an overall design plan, then Party A should be able to do it by itself, and it doesn’t fully reflect the necessity of asking our research team to solve the problem.”
Li Yabo Chang Haonan was very satisfied with his first sentence.
Although I kind of dislike the Haofei Group.
“After trying several different layup solutions, I found that the orthogonal lamination is significantly better in terms of ability to withstand shear loads and lateral loads, but this result is inconsistent with what I have done at Haofei Group What I saw when I was on a business trip there was different..."
"Also, even if they are the same orthogonal stack, my two calculation results will be different..."
"..."
In a daze, Chang Haonan seemed to have learned from the other party. I saw myself a few years ago.
Subjective initiative is full.
Of course, after all, he is a true undergraduate, so there is definitely still a huge gap between his ability and his own back then.
However, this is not the most important thing.
“This is not surprising.”
He listened quietly to what the other party said, and then replied:
“The anisotropy of this type of carbon fiber reinforced composite material It is very complex, the interlayer strength is unstable, and the thermodynamic and mechanical properties of the fiber and matrix are very different. We, or not only us, but the world still do not understand enough about the nature of this material. ”
< br>“So, although the current TORC Multiphysics can use your method to model the structure of multi-layer composite materials, it is unable to perform accurate numerical simulations in this case.”
"This is why I told you before, as long as we can design a theoretically feasible overall plan."
Hearing Chang Haonan's explanation, Li Yabo showed a slightly embarrassed look on his face:
br>
"This...it turns out to be like this..."
He scratched his head as he spoke:
"Then isn't all this useless effort..."
>
Originally, Li Yabo wanted to secretly do the whole job and shock the teacher for a whole year.
In the end, I didn’t finish my job, and I had to go to the teacher to help find the reason.
“That can’t be said.”
Chang Haonan could roughly guess what the other party was thinking, and shook his head with a smile:
“After all, the whole modeling You still have to go through the calculation process yourself. It will be a rare experience for your future research work.”
"Some experiences can only be summed up in failure."
Li Yabo nodded with some disappointment.
But Chang Haonan’s next words made his eyes light up:
“However, if you are really interested in the microstructure of composite materials, then I can directly buy you one. Collect relevant equipment and materials and study them experimentally”
“Really...really?”
Li Yabo could hardly believe his ears:
“I asked before when I went to Haojing on a business trip, the equipment and materials are very expensive...”
Obviously, he had already The situation has been understood secretly.
Before Li Yabo finished speaking, Chang Haonan waved his hand:
"The equipment used for laboratory-level research is not the same as their industrial production, and the cost is not that exaggerated. You Teacher, I can still afford this amount of money.”
"It's just that you have to think clearly. Strictly speaking, this is materials science, not the field of structural mechanics. Experimental research is far more difficult and troublesome than numerical calculations..."
"I have thought it through."< br>
Li Yabo replied firmly.
"That's good."
Seeing that his student is so persistent, Chang Haonan can no longer discourage him:
"With your current design, it is no problem to take it to graduate school."
He pointed to the modeling on the computer screen:
"So, in the next time, I will officially treat you as a graduate student."
Hearing this, Li Yabo couldn't help but sit up straight.
Although he did not express his position, this action said everything.
Chang Haonan nodded slightly when he saw this, and then said in a solemn tone:
"I will give you one month to write a proposal report on the research on the microstructure of composite materials to me, and attach your Required experimental equipment and materials. ”
“If there are no problems with the report, I will prepare it for you as soon as possible. Do you understand?”
(End of this chapter)