At the same time, Jinghang University is here.

Chang Haonan's research on high-speed rolling bearings has also entered the most critical stage.

For him, if he really just wants to design a single bearing product, whether it is for turbofan 9 or turbofan 10, it is actually not difficult.

During this period of time, scattered things have been done, and 300 scientific research points have been saved up again, and a bearing design project has been completed, which is enough.

But today's Chang Haonan is no longer here.

When I was just reborn, there was no way to spend scientific research points to do specific projects, after all, if I didn't have some real and convincing results, I couldn't just rely on words to move others to change the direction of national-level policies-

Even if his mouth cannon skills were full, he didn't have a channel to speak at that time.

However, it was back then, and now it is now, and now Chang Haonan has the ability to influence the direction of the industry, and the height of looking at things is definitely different.

The reason why he wants to bring together several top research groups engaged in high-speed bearing research in the system of the Science and Industry Commission is to speed up the research progress, and is naturally ready to promote the level of the entire industry.

And even with a tool like TORCH Multiphysics, which is an order of magnitude more computationally efficient than in the past, to achieve this goal, it is more important than the results to obtain the data obtained during the research process.

"Mr. Chang! The results of the first experiments are out! ”

A young man in a blue overalls and goggles walked quickly to Chang Haonan, who was looking at the table in front of him with a row of bearings.

Jing Zhang is a Ph.D. student in Qinli Wang's group.

is the same age as Chang Haonan, and if he has to say it, he is even a few times higher than the latter.

When he was first named by his mentor to do a project in Beijing, he actually wanted to refuse.

For graduate students, especially those in this era, traveling is definitely a chore.

Helplessly, the person had to bow his head under the eaves, and was finally dragged over by Wang Qinli.

However, after seeing Chang Haonan's research efficiency before and understanding the research topics they will be responsible for next, he quickly and wholeheartedly devoted himself to the assigned work.

After this period of hard work, if he hadn't recited the ancestral teachings of respecting teachers and respecting the Tao, I am afraid that Wang Qinli would have forgotten.

And the experiment in his mouth is also Chang Haonan's concentrated test of his achievements during this time.

"Let's go, let's see."

Chang Haonan put down the form in his hand, put the pen into the breast pocket of his lab coat, and strode to another room not far away.

There, a dozen or so devices spinning at high speed were emitting a low roar.

Although the experiment has ended, it is obviously impossible for the device to stop immediately from 15,000 revolutions per minute in the high-speed rotation state, so the bearing being tested inside will have to wait a while before being removed.

However, the shock and vibration data recorded during the entire process can still be viewed.

Chang Haonan went straight to the computer with the No. 1 logo.

Wang Qinli, Zhang Qinggang and other professors who were in charge of different research contents consciously gave him a position with the best angle.

According to the recorded data results, the RMS amplitude of the rotor acceleration signal before the maneuvering flight is 0.1190m/s^2, and the RMS amplitude during the maneuvering flight is 0.1957m/s^2, an increase of 64.45%; The RMS amplitude of the bearing contact force pulse signal before the maneuvering flight is 19.5124N, and the RMS amplitude during the maneuvering flight is 37.4275N, an increase of 91.81%, which is very close to the prediction result of your improved mathematical model, and the comprehensive error is within 8%. ”

Wang Qinli's voice trembled when he reported the results.

You know, the model he improved on the basis of the Jones model can control the dynamic performance prediction error of low-speed bearings under normal working conditions to about 15%.

This has made Wang Qinli feel that he can leave his name in the field of machining, and even considered naming it as the Qinli model for a while.

However, Chang Haonan only spent less than half a month of effort, and he actually improved the accuracy to a new level?

And Zhang Qinggang next to him had completely forgotten that there were other people around, and almost hugged the screen and muttered to himself:

"It's too accurate, it's too accurate......"

For an engineering model, this accuracy is indeed almost like a dream.

However, Chang Haonan was not surprised by this, in fact, when everyone held the first meeting, the idea proposed by Wang Qinli was already quite forward-looking, and he made some modifications on it, taking into account several factors that were difficult to calculate due to excessive nonlinearity, such as assembly interference, temperature difference and external maneuvering overload, and the accuracy was greatly improved.

After looking at the data on several computers in a row, everyone's attention had shifted to the experimental equipment not far away.

In fact, the dozen or so devices that are decelerating next to them have been running continuously for hundreds of hours.

For the life equivalent acceleration test, these bearings have also reached the end of their life, which can be seen from the obvious anomalies in the data recorded on the computer compared to the steady-state operation.

The bearings tested in each piece of equipment are specially designed with typical structural parameters.

According to Chang Haonan's calculations before the experiment, each of them would correspond to a different failure mode.

The dynamic performance prediction is only a small part of the content, and in the end, it is still whether the calculation of the failure mode of the bearing can correspond to the actual situation.

If it can, it can directly make Huaxia's bearing industry, and even the entire machinery manufacturing industry enter a new era.

An era of being able to overtake on straights!

Although this process may not be completed in three or two years.

But for researchers in Huaxia, difficulty has never been a problem.

The problem is that there is no hope in the past.

A better product means more users, and more users means more data is generated and more valuable, which in turn can be fed back to further optimize the product.

Basically all high-end industries meet this virtuous cycle model.

In this case, if you want to achieve transcendence, you must either wait for the external environment to change drastically, or simply change the track.

And Chang Haonan's set of things is completely unreasonable to break this cycle.

In a better algorithmic framework, the amount of data I need to optimize the product may only be one-tenth of yours or even less, so this game is different.

Soon, more than a dozen experimental equipment stopped running one after another.

After a period of cooling, the operator in charge of the experiment removed the bearings one by one.

"The No. 1 bearing, according to calculations, has a maximum contact stress of 2500Mpa during the working process, and the maximum shear stress of the subsurface layer is about 125μm from the surface, and the failure mode is speculated to be fatigue spalling of the origin of the subsurface."

There is no need to even look at the label attached to the equipment, Chang Haonan can already retell the calculation results of each bearing.

"That's right, the spalling area is about 50mm×15mm, the subsurface butterfly tissue is about 105~129μm from the raceway surface, and the maximum length is about 40μm......"

"The No. 2 bearing, the maximum dn value during the working process is 2.38×106mm·r/min, the instantaneous temperature of the contact area is more than 300 °C, and the failure mode is presumed to be the fracture of the bearing ring and cage."

"No. 3 Bearing, Bearing Raceway and Cage Surface Wear and Failure ......"

"Number Four ......"

“……”

"No. 16, Origin Pitting Failure ...... of Bearing Raceway Surface"

When Chang Haonan reported the failure of the last test subject, there was no sound in the entire laboratory except for the humming sound generated when the computer host was running.

"The result?"

After a few seconds of silence, Chang Haonan turned around and looked at the dozens of people in front of him.

Zhang Jing was holding an experimental notebook in his hand, and at the end of each line of content on it was a check mark.

"Both...... It's all right! ”

(End of chapter)